Search is not available for this dataset
query
stringlengths 1
13.4k
| pos
stringlengths 1
61k
| neg
stringlengths 1
63.9k
| query_lang
stringclasses 147
values | __index_level_0__
int64 0
3.11M
|
|---|---|---|---|---|
Power Allocation for NOMA System via Dual Sub-gradient Descent | Non-orthogonal multiple access (NOMA) has attracted great attention as a promising downlink multiple access technique for the next generation cellular networks (5G) due to its superior spectral efficiency. Power allocation of multi-user scenario in NOMA is a challenging issue and most of existing works focus on two-user scenario. In this work, we develop a dual sub-gradient descent algorithm based on Lagrange dual function to optimize multi-user power allocation for the multiple-input single-output (MISO) downlink NOMA system. The objective function is a non-convex optimization problem and we can solve it with a log-convex method and an approximation based approach. Numerical results demonstrate that the proposing scheme is able to achieve higher capacity performance for a NOMA transmission system compared with the traditional orthogonal multiple access (OMA) with a few iterations. | The paper presents a VHDL-AMS based approach to the Switched-Current (SI) Sigma-Delta Modulator design. EDA tools are presented, which translate the prototype VHDL-AMS description into SI realization. Another tool helps the designer to create the layout. The paper also describes a new proposed current mode comparator, which is used in the design. Postlayout simulation results are presented. | eng_Latn | 13,300 |
NbTiN/SiO/sub 2//Al tuning circuits for low-noise 1 THz SIS mixers | Waveguide SIS mixers in which Nb/Al-AlO/sub x//Nb tunnel junctions are integrated with NbTiN/SiO//sub 2//Al tuning circuits are shown to yield receiver noise temperatures as low as 565 K at 970 GHz. Analyzing the noise and gain of one such receiver, it is shown that the NbTiN ground plane is low-loss (<0.6 dB) at 970 GHz. These results are in good agreement with results obtained previously with a quasi-optical mixer incorporating a similar tuning circuit. A decrease in sensitivity above 1 THz is attributed to increasing loss in the NbTiN. | By employing the notion of communication sequence and lifting techniques,a class of multiple-input-multipleoutput(MIMO) networked control systems(NCSs) with communication constraints is modeled into an extended state-space model with non-uniformly sampling in which control and scheduling are integrated.Based on linear matrix inequalities(LMIs),the output feedback control law is designed.The new model has the pattern of time-invariant discrete-time system,and it affords a new way for the analysis and research of NCS with communication constraints.The proposed controller with a single structure can not only overcome restricted from the cycle of original communication sequences and avoid multiple controllers periodically switching,but also reduce the network load and improve the performance of the system effectively by scheduling the sampling frequency based on the characteristics of the signal. | eng_Latn | 13,301 |
A surface equivalence-based method to enable rapid design and layout iterations of coupled electromagnetic components in integrated packages | A novel methodology is presented that expedites the electromagnetic analysis in the design cycle of individual layout components in close proximity to other radiating and electromagnetic structures. The proposed method retains all the advantages of a surface based moment method technique, but avoids explicit modeling of the interactions between the object under design and the neighboring ones, without compromising on the accuracy of capturing the electromagnetic coupling between them. As a result, the simulation time in an individual design cycle is greatly reduced. | We investigate multirate multicarrier code-division multiple-access (MC-CDMA) downlink systems with multicode transmission. Specifically, we design a new linear equalizer that outperforms the minimum mean-squared error (MMSE) per-carrier equalizer, without requiring the spreading codes of the interfering users. The complexity of this new linear equalizer is similar to that of the MMSE per-user equalizer, which however needs the spreading codes of the interfering users. Simulation results validate the effectiveness of the proposed equalizer, especially when there are few interfering users. | eng_Latn | 13,302 |
Analysis of Passive Intermodulation Effect on OFDM Frame Synchronization | Passive intermodulation can lead to a decrease in the performance of frame synchronization for the orthogonal-frequency-division multiplexing (OFDM) systems. In this paper, the Schmidl&Cox algorithm of frame synchronization is simplified by difference calculation to avoid overly complicated analysis. The statistical properties of time metric function in the presence of passive intermodulation interference are obtained by Gaussian distribution fitting. The closed form of false and missing detection probabilities are derived to evaluate the frame synchronization performance. Finally, simulations are conducted to demonstrate the validity of the analysis results. | Follower jamming is a class of jamming way which is very harmful to the frequency hopping system. Low density parity check (LDPC) code is employed in frequency hopping system to combat follower jamming in this paper. The characteristics of follower jamming is introduced firstly, and then the model of LDPC coded FH system is built. The classical Progressive edge growth algorithm is used to construct the parity check matrix of LDPC code, and the sum-product algorithm is applied to obtain the optimum decoding performance. The simulation results show that the proposed system has outstanding anti-jamming capability, which is also compared with the traditional Reed-Solomon (RS) coded system. | kor_Hang | 13,303 |
Mechanical intermittent water flooding technique | A new intermittent water flooding technique is developed . A tractor is taken as power unit for pulling a tanker and driving a water injection pump. The pressure water flows into a tube through a rubber hose, a water flood gun and a snap joint, then the water is injected into formation through the check valve in the tube. The check valve can prevent the fluid flow in pipeline and formation from spilling over. Because this technique does not require pressure manifold and the high\|pressure pump station, the investment and operation costs are reduced by over 40% in comparison with the conventional water injection system. This technique is suitable for the oilfields with stripper and low permeability, and it can be combined with the intermittent recovery technique taking screw pump as a power unit. | This chapter is dedicated to impulse radio as it is a very prominent form of UWB. Initially, impulse radio (IR) is introduced and generic transceiver architecture for IR is presented. Then, common and custom tailored pulse shapes for impulse radios are discussed. Various IR modulation techniques are presented and their performance is analyzed. To enable multiple accesses, a technique known as time hopping (TH) is introduced and it is integrated into various modulation techniques. Finally, the impact of the various antenna types on the transmitted and received UWB signal is investigated. | eng_Latn | 13,304 |
Development of Home Appliances Controller with DTMF Signal | This paper presents the development of home appliances controller design that utilizes Dual-Tone Multi Frequency (DTMF) signal from the landline telephone. The device contains microcontroller that links with a decoder IC that converts DTMF signal into binary codes and vice versa. It is proven that the device enables residents to send and receive signal from outside the house; thus enabling them to control the appliances at home. Finally, the results from an experimental setup found that the device is proven to be working. | Chalmers University of TechnologyDepartment of Information TheoryS-412 96 Gothenburg, Swedenphone +46 31 772 17 51 or +46 70 565 48 20fax +46 31 772 17 48e-mail [email protected]. Novel coherent detectors for DQPSKand π/4-DQPSK on fading channels are pre-sented. The phase reference for the decisiondevice is derived by mean square error estimationof the fading process. A finite impulse responsefilter is used for this purpose. The decision deviceis a traditional coherent detector. Both 1 and 2stage detectors are considered. The proposeddetectors show significantly better performancein fast fading compared to a differential detector. | eng_Latn | 13,305 |
Application of the ONETRAN and TIMEX codes to shielding problems | Some of the unique features of importance to shielding calculations available in the ONETRAN and TIMEX codes are described. The results of two typical shielding problems which display the advantages of these two codes are presented. 3 figures. | Remote observing with Caltech's millimeter wave array at the Owens Valley Radio Observatory (OVRO) is being extended to use the graphical capabilities commonly available on computers today. To allow the instrument to be clearly presented to the user, a rich interface has been developed that combines the use of color highlights, graphical representation of data, and audio. Java and internet protocols are used to extend this interface across the Web to provide remote access. Compression techniques are used to enable use over low bandwidth links. This paper presents the design goals, implementation details, and current status of this effort with emphasis on the monitoring of the array. | eng_Latn | 13,306 |
Method and system for alerting a user of the mobile communication device | The present invention provides a method to alert the user of a mobile communication device (110) (200) and a control system (110). The method includes the steps of detecting that the vehicle (114) receiving a communication request at the mobile communication device within (216), in response to receiving the communication request, whether a predetermined vehicle condition is present (224) and, based on the presence of a given vehicle state, and the step (226) to assign a predetermined warning mode, in accordance with a predetermined warning mode assignment, the step of warning about the communication request to the user of the mobile communication device (234) If, consisting of. | A neural network based multiuser detector for DS-CDMA systems is presented. By using the minimum output energy criterion, the detector is formulated as a constrained optimization problem and is then resolved efficiently by using neural network. The computational complexity of the proposed detector is only O(N), making its real-time implementation possible. It is shown that the proposed method is superior in computational efficiency to the conventional CRLS blind algorithm. | eng_Latn | 13,307 |
Optical module, optical device and wearable display device | An optical module, an optical device and a wearable display device are disclosed. The wearable display device (10) comprises a micro display module (112) for outputting a display source; the optical module (113) is used for magnifying and projecting the display source to an exit pupil (P) and includes an first optical module (113A) consisting of a first lens (L1) having positive focal power, a second lens (L2) having negative focal power, and a third lens (L3) having positive focal power, and includes a second optical module (113B) consisting of a fourth optical element (L4) being composed of a first aspheric surface (F7), a second aspheric surface (F9) and a deflected face (F8) and having positive focal power. The deflected face (F8) is used for changing the optical path direction of the first optical module (113A) to the direction of the exit pupil (P). The optical module (113) adopts numbered optical elements to achieve image display with high quality. | As the demand of high quality service in next generation wireless communication systems, a high performance of data transmission requires an increase of spectrum efficiency and an improvement of error performance in wireless communication systems. In this paper, we propose a multi-user multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) system with adaptive modulation and coding to improve system capacity with maintaining good error performance. The results of computer simulation show the improvement of system capacity in Rayleigh fading channel. | eng_Latn | 13,308 |
A 5.6 GHz Low Power Balanced VCO in 0.18 $\mu$m CMOS | A 5.6 GHz balanced voltage-controlled oscillator (VCO) is designed and implemented in a 0.18 mum CMOS 1P6M process. It consists of two single-ended complementary Colpitts LC-tank VCOs coupled by two pairs of varactors. At the supply voltage of 1.2 V, the output phase noise of the VCO is -119.13 dBc/Hz at 1MHz offset frequency from the carrier frequency of 5.6 GHz, and the figure of merit is -190.29 dBc/Hz. Total VCO core power consumption is 2.4 mW. Tuning range is about 600 MHz, from 5.36 to 5.96 GHz, while the control voltage was tuned from 0 to 1.2 V. | In this paper we present a method for reconfiguring Virtual Objects (VOs) during run-time. VOs are semantic descriptions of ICT objects and the associated physical objects and phenomena they observe. VOs also include software modules to expose ICT object functionalities as IoT services for re-use. In our case study we show, by using an analytical model, how the energy efficiency of a wireless battery powered weather station (WS) can be improved. We introduce descriptions of the available operating modes and store them in the WS semantic description. These operating modes of the WS's VO are linked with the ability of the ICT object to change the compression method used to transmit information during run-time. We evaluate the energy efficiency and latency of three operating modes, namely uncompressed, lossy and lossless modes. The results show that the possibility to re-configure the operating mode during run-time from uncompressed to lossy mode lowers the total energy for transmission to 47.9%. | kor_Hang | 13,309 |
Optimal delay-power tradeoff in sparse delay tolerant networks: a preliminary study | In this paper we present a first attempt to study analytically the tradeoff between delivery delay and resource consumption for epidemic routing in Delay Tolerant Networks. We assume that the nodes cooperate in order to minimize a common cost equal to a weighted sum of the packet delivery delay and the total number of copies, which is strongly related to the power consumption. In this framework we determine the best policy each node should deploy in a very simple scenario where all the nodes have perfect knowledge of the system status. The result is used as an ideal reference to evaluate the performance of some heuristics proposed, investigating potential performance improvements and configuration criteria. | A novel 2- and 3-D space spectral domain analysis (SSDA) simulator for microstrip and CPW transmission line discontinuities is described. The characteristic impedance, effective dielectric constant, and S-parameters of different type of transmission lines and discontinuities shapes can be computed. The topology of structure and the computed results are displayed using a graphical interface. The simulator has been implemented on Sun Sparcstations. > | eng_Latn | 13,310 |
Interface implementation of DSP based on 8-bit parallel A/D converter MAX153 | Digital signal processing is one of the most important technology in digital communication. The paper brought forward an interface method of MAX153 and DSP on the basis of MAX153's features, and provided the principle diagram and the program of DSP. | Summary A low frequency noise analysing system is set up with a multi-channel detector. The multi-channel detector includes a PCD Image Sensor which has 256 sensing elements. Light output of a laser diode is divided into various wavelengths. The light spectral intensities are measured at various wavelengths. | eng_Latn | 13,311 |
The wireless communication apparatus and radio communication method | A wireless communication device for communicating with an upper device and a lower device, is provided with a beacon reception unit and a beacon transmission unit. The beacon reception unit receives first regular beacon signals (351) transmitted from the upper device. When the beacon reception unit receives the first regular beacon signal (351), the beacon transmission unit transmits, to the lower device, a second regular beacon signal (351) for synchronizing the clock of the lower device. When the beacon reception unit cannot receive the first regular beacon signal (351), the beacon transmission unit transmits a provisional beacon signal (352) to the lower device, the provisional beacon signal indicating that the clock of the station itself cannot be synchronized with the clock of the upper device. | In this paper a programmable and area-efficient decoder architecture supporting two decoding algorithms for Block-LDPC codes is presented. The novel decoder can be configured to decode in either TPMP or TDMP decoding mode according to different Block-LDPC codes, essentially combining the advantages of two decoding algorithms. With a regular and scalable data-path, a Reconfigurable Serial Processing Engine (RSPE) is proposed to achieve area efficiency. To verify our proposed architecture, a flexible LDPC decoder fully compliant to IEEE 802.16e applications is implemented on a 130nm 1P8M CMOS technology with a total area of 6.3mm2 and maximum operating frequency of 250MHz. The chip dissipates 592mW when operates at 250MHz frequency and 1.2V supply. | eng_Latn | 13,312 |
Prophylactic cranial irradiation with combined modality therapy for patients with locally advanced non-small cell lung cancer. | Central nervous system (CNS) metastasis is a significant problem for many patients with non-small cell lung cancer (NSCLC). The earlier data reported a high incidence of CNS metastasis in patients with locally advanced NSCLC who were treated with radiotherapy alone. However, poor control of both thoracic and extracranial systemic disease dominated the results of the early trials. The risk for CNS metastasis as the first site of failure remains a significant concern for patients who have completed modern combined modality therapy. With improvements in the treatment of thoracic and systemic disease, there is renewed interest in prophylactic cranial irradiation (PCI). The results from the Radiation Therapy Oncology Group (RTOG) trial of PCI to prevent CNS relapse in patients with locally advanced NSCLC are anticipated. | In cloud radio access networks (C-RANs), the baseband processing of the available macro- or pico/femto-base stations (BSs) is migrated to control units, each of which manages a subset of BS antennas. The centralized information processing at the control units enables effective interference management. The main roadblock to the implementation of C-RANs hinges on the effective integration of the radio units, i.e., the BSs, with the backhaul network. This work first reviews in a unified way recent results on the application of advanced multiterminal, as opposed to standard point-to-point, backhaul compression techniques. The gains provided by multiterminal backhaul compression are then confirmed via extensive simulations based on standard cellular models. As an example, it is observed that multiterminal compression strategies provide performance gains of more than 60% for both the uplink and the downlink in terms of the celledge throughput. | eng_Latn | 13,313 |
Rectangular tunnel double-bundle anterior cruciate ligament reconstruction with bone-patellar tendon-bone graft to mimic natural fiber arrangement. | We describe our current technique of anatomic, double-bundle (DB), rectangular tunnel anterior cruciate ligament (ACL) reconstruction with bone-patellar tendon-bone (BPTB) graft. This technique mimics the natural, or anatomic, arrangement of the native ACL fibers. This technique has the following advantages: (1) creation of a DB ACL reconstruction with a single BPTB graft; (2) maximization of graft-tunnel contact area; (3) containment of the tunnel apertures within the anatomic ACL attachment footprint; (4) rotational control of the graft within the tunnels during and after fixation; and (5) preservation of notch anatomy. | In this paper, we consider utilizing the space-time codes in the wideband CDMA system. We assume that there are multiple resolvable paths in the frequency selective fading channel. Analytical results show that in addition to spatial diversity, another diversity gain called multipath diversity is achievable. Performance criterion for full space multipath diversity gain is analyzed. We consider both the case that the receiver has the ideal channel state information and the case that there are errors in the channel state information available to the receiver. A RAKE receiver is used in the CDMA system to gain the multipath diversity. We derive the generalized RAKE receiver structure for the space-time block coding (STBC) coded wideband CDMA systems. The simulation results demonstrate the additional gain guaranteed by the multipath diversity. | eng_Latn | 13,314 |
Superiority of Superposition Multiaccess With Single-User Decoding Over TDMA in the Low SNR Regime | This paper studies the Gaussian multiaccess channel with multiantenna basestation in the low signal to noise ratio (SNR) regime. We compare the spectral efficiencies of the optimal superposition channel sharing scheme and two simple alternatives: the time division multiaccess (TDMA) scheme and superposition multiaccess with single-user decoding (SSD). Due to the fact that SSD, but not TDMA, exploits the multiuser multiplexing gain, the relative spectral efficiency of SSD over TDMA grows drastically as the number of antennas at the basestation increases. The results suggest that, in the low SNR regime with multiple antenna basestation, TDMA's suboptimality can no longer be offset by its simplicity since SSD can achieve much higher spectral efficiency while the simplicities of the two channel sharing schemes are similar. | A best and efficiently to provide a system and method capable of setting up a resource by the receiving device and the wireless network. A transmitting device several QoS parameters negotiated, signaling to the receiving devices of the session during the session setup procedure. Guaranteed bit rate, maximum bit rate, and transfer delay is signaled to the receiving device. New session description protocol attribute defined for QoS parameters described above, which are executed by the Session Initiation Protocol message. The receiving device uses these SDP attributes may be in the PDP activation, to negotiate wireless network and QoS parameters itself. The receiving device uses these parameters to resources such as jitter buffer for voice and video can be set accordingly. .FIELD 4 | eng_Latn | 13,315 |
Three-Mode Reconfigurable Rectifier for DC-DC Converters with Wide Input Voltage Range | Novel reconfigurable rectifier circuit is presented. It features three operating modes: full-bridge rectifier, voltage doubler rectifier, voltage quadrupler rectifier. After the rectifier topology is introduced, a case study dc-dc converter based on quasi-Z-source full-bridge topology is presented. An experimental prototype was assembled to verify concept feasibility. The assembled converter is suitable for the global maximum power point tracking owing to the wide input voltage range achieved. DC voltage gain theoretical expressions are verified experimentally, and measured efficiency is given. | This paper introduces the optimal widely linear (WL) minimum variance distorsionless response (MVDR) beamformer for the reception of an unknown signal of interest (SOI) corrupted by potentially second order (SO) noncircular background noise and interference. The SOI, whose waveform is unknown, is assumed to be SO noncircular with arbitrary noncircular properties. In the steady state and for SO noncircular SOI and/or interference, this new WL beamformer, that is derived from an original orthogonal decomposition, is shown to always improve the performance of both the well-known Capon's beamformer and a WL MVDR beamformer introduced recently in the literature. This optimal WL MVDR beamformer is first introduced and some of its performance are analyzed. Then, several adaptive implementations of this optimal WL beamformer are presented. | eng_Latn | 13,316 |
A 100 W tri-band LDMOS integrated Doherty amplifier for LTE-advanced applications | A Doherty amplifier architecture with integrated input splitter and output combiner, allowing bandwidth extension, is described. Based on this approach, a very compact 100W symmetrical LDMOS Doherty amplifier has been designed and characterized in the 1.805 to 2.17 GHz frequency band. It can achieve 15.9 dB maximum gain, 46 to 48 % back-off efficiency and can be linearized at −59.3 dBc ACPR level with a 10 MHz wide LTE signal. The fabricated amplifier is 50 × 50 mm2. | This paper addresses the problem of channel and propagation delay estimation in asynchronous DS/CDMA systems. We consider the uplink connection in DS/CDMA with long spreading codes. The MIMO stochastic gradient algorithm proposed in [6] is estimating a linear combination of the channel impulse responses and the propagation delays. This estimate suffices for the equalization purposes. The propagation delays are estimated with a simple matching scheme. | eng_Latn | 13,317 |
Downlink Capacity of Distributed Antenna Systems in a Multi-Cell Environment | In this paper, the downlink performance of a distributed antenna system (DAS) with random antenna layout is investigated. We address the problem of characterizing the downlink capacity with the generalized assumptions: (a1) per distributed antenna power constraint, (a2) generalized mobile terminals equipped with multiple antennas, (a3) a multi-cell environment. Based on system scale-up, we derive a good approximation of the ergodic downlink capacity by adopting random matrix theory. We also propose an iterative method to calculate the unknown parameter in the approximation. The approximation is illustrated to be quite accurate and the iterative method is verified to be quite efficient by Monte Carlo simulations. | The data acquisition system for the CMS experiment at the Large Hadron Collider (LHC) will require a large and high performance event building network.Several architectures and swithch technologies are currently being evaluated.This paper describes demonstrators which have been set up to study a small-scale event builder based on PCs emulating high performance sources and sinks connected via Ethernet or Myrinet switches.Results from ongoing studies,including measurements on throughput and scaling,are presented. | eng_Latn | 13,318 |
Design and performance of a spread spectrum data communications system using delta modulation with a dithered clock | Abstract : Digital modulation schemes and spread spectrum techniques are of major importance in modern communications. This thesis investigates a delta modulation/demodulation scheme and direct sequence spreading of the digital data. The clock rate is dithered to enhance the low probability of intercept advantage of spread spectrum. The circuitry incorporates small and medium scale integrated circuits. Experimental results are presented in some detail. Good quality voice and music were recovered using a fixed bit rate as low as 10 kbits/sec and a clock dither range of 40%. (Author) | A finite difference scheme for the one-dimensional space fractional diffusion equation is presented and analysed. The scheme is constructed by modifying the shifted Grunwald approximation to the spatial fractional derivative and using an asymmetric discretisation technique. By calculating the unknowns in differential nodal point sequences at the odd and even time levels, the discrete solution of the scheme can be obtained explicitly. We prove that the scheme is uniformly stable. The error between the discrete solution and the analytical solution in the discrete l 2 norm is optimal in some cases. Numerical results for several examples are consistent with the theoretical analysis. | eng_Latn | 13,319 |
New Generation of Clusterable In-FEEP Emitters | Based on the lessons learned during the GOCE Microthruster Program, ARC Seibersdorf research is now developing a new generation of clusterable InFEEP emitters, which shall enable an operation with a single PCU with drastically reduced costs and complexity, and shall operate each single emitter within the cluster at a low and thus safe thrust level. A cluster of these new emitters will allow thrust levels higher than 100 μN and increased total impulse capability. This paper presents an overview of the lessons learned during the GOCE activity, their implementation on the design of the new emitters, preliminary results which include a 1500h endurance test of the single emitters, as well as a characterization of a first cluster prototype. | Chalmers University of TechnologyDepartment of Information TheoryS-412 96 Gothenburg, Swedenphone +46 31 772 17 51 or +46 70 565 48 20fax +46 31 772 17 48e-mail [email protected]. Novel coherent detectors for DQPSKand π/4-DQPSK on fading channels are pre-sented. The phase reference for the decisiondevice is derived by mean square error estimationof the fading process. A finite impulse responsefilter is used for this purpose. The decision deviceis a traditional coherent detector. Both 1 and 2stage detectors are considered. The proposeddetectors show significantly better performancein fast fading compared to a differential detector. | kor_Hang | 13,320 |
Double-beta decay in the pseudo SU(3) scheme | Abstract We estimate the double-beta half-life in the two-neutrino mode of several heavy deformed nuclei using the pseudo SU(3) shell-model scheme. In this approach, we used a recently developed summation procedure, avoiding the closure approximation. We find forbidden decays for five potential double-beta emitters and finite values for the half-life of six other nuclei, one of them strongly inhibited. These forbidden decays represent a possible test of our model and up to now the predictions are in good agreement with the available experimental data. | Fully digital transmitters have been thoroughly explored over the last few years to develop a novel type of agile, reconfigurable, multi-band, multi-standard and highly-efficient transmitters. However, with regard to agility and reconfigurability, current state-of-the-art approaches are still very restrictive. This paper proposes a new architecture based on a tunable delta-sigma modulator suitable for designing RF fully digital transmitters either in single-carrier or in dual-carrier scenarios. A 2-path polyphase decomposition was also developed to optimize some figures of merit, such as SNR and EVM, and to demonstrate the scalability of this type of modulator. This novel architecture has been successfully implemented and validated on an FPGA-based transmitter for single- and dual-carrier scenarios. | eng_Latn | 13,321 |
Hybrid linear-iterative detection algorithms for MIMO CDMA systems in multipath channels | We assume a CDMA downlink multiuser scenario, where the base station is equipped with multiple transmit antennas, and each user has multiple receive antennas. For this setup we propose a new, computationally effective MIMO multiuser detector for frequency selective channels. We exploit the fact that the interference mainly comes from the spatial domain, while the residual interference is due to temporal dispersion and multiuser interference. This motivates us to suppress the residual interference in a linear fashion, while combating the spatial interference iteratively. This approach is an efficient performance-complexity tradeoff between fully iterative and linear detectors. | Today, SiGe HBT cut-off frequencies are higher than 230 GHz (Chevalier et al., 2004) and this increase allows new millimeter wave (MMW) applications on silicon such as 60 GHz WLAN and 77 GHz automotive radar. One of the success keys is then the passive integration. This study focuses on a 52 GHz silicon integrated antenna and related feeding transmission line (TL) topics. Double slot antenna integrated in a standard BiCMOS process and 40 GHz coplanar patch antenna (2.3dB gain @ 40 GHz) with a coplanar waveguide (CPW) feed line are depicted and characterized. Integrated TL achieved on standard STMicroelectronics (ST) BiCMOS, CMOS and silicon on insulator (SOI) technologies are described, performances are given (<0.7 dB/mm losses @ 80 GHz for SOI CPW). A full modeling has been developed up to 80 GHz with new approach for CPW on silicon technology due to passivation layer. | eng_Latn | 13,322 |
A novel high PSRR bandgap over a wide frequency range | This paper describes a novel bandgap reference with high PSRR over a wide frequency range. The design utilizes an internally regulated supply voltage without high gain feedback loop. Thus improve PSRR even at high frequency. Additional transistors are added to further improve supply rejection and minimize the second order effect. The circuit is implemented in 0.25µm CMOS technology. It generates a reference voltage of 1.262V which has a voltage variation versus temperature of 0.1% from −20C to 90C. It has a PSRR of 85dB at 1kHz and still 64dB at 1MHz. | This paper presents the dynamic RF link estimation result for telemetry system of KSLV (Korea Space Launch Vehicle)-I. In particular, it utilizes the parameters of the instantaneous vehicle antenna gain pattern in three dimensions, the improvement by polarization diversity combiner at the ground receiver, and the free space propagation loss. The structural transformation and discontinuity of ground plane after the separation events of nose fairing, stage, and spacecraft, are also included in this analysis. As a consequence, the prediction of link variation has been performed in accordance with ARDP (Antenna Radiation Distribution Plot) and look angle trace of vehicle. In addition, the optimum position of onboard antennas has been investigated to provide better RF link margin in the nominal trajectory. | eng_Latn | 13,323 |
Design and simulation of wireless communication system based on SystemView | The modulation module and RF emission module in transmitter system,and RF receive module and demodulation module in receiver system of modern wireless communication system are analyzed.The SystemView software was used as platform to construct a model of modern wireless communication system.The simulation analysis for waveform change and spectrum transformation can make people understand complex theory problem in a short time,understand and master the modern wireless communication system. | Starting from 2.5D MHD modelling of solar flares on a global scale we calculate (using the PIC and test-particle simulations) the radio and X-ray emissions generated in solar flare reconnection. Our results – the radio and X-ray spectra and brightness distributions, and their dynamics – are directly comparable with observations providing thus a test of particle acceleration models as well as of the ‘standard’ global flare scenario. | eng_Latn | 13,324 |
Fairness of adaptive multimedia applications | We present a scalable scheme called the direct adjustment algorithm (DAA) for adapting the transmission rate of multimedia applications to the congestion level of the network. The DAA is based on the end-to-end real time transport protocol (RTP). Results achieved through simulations and measurements suggest the efficiency of the scheme in utilizing the network resources and decreasing the loss rates. However, with no support from the network, adaptive applications tend to be unfair towards long distance connections and lead to the starvation of competing TCP connections. | We propose a novel machine learning based equalization algorithm for bandwidth-limited IM-DD PON in C-band. 50Gb/s/λ. PAM4 transmission is demonstrated over 20km SSMF using a 10G-class transmitter with 21dB loss budget without amplification. | eng_Latn | 13,325 |
DC Link Voltage Stabilisation in Hybrid Renewable Diesel Systems | Constant Speed diesel generators have been used in remote and isolated areas to provide electricity for over half a century and in this time they have remained largely unchanged. Although they have been mated with other forms of generation, especially wind and photovoltaic successfully but generally to the detriment of the diesel generator. To alleviate this problem in this paper a modelled a variable speed diesel generator (VSDG) has been modelled as part of a hybrid renewable system. The benefits of a VSDG are explained and results show the fuel savings possible over a standard diesel generator. An experimental test rig has been built and the DC link stability has been assessed with and without different forms of short term energy storage. It is shown that supercapacitors can be utilised for maintaining the DC link voltage effectively. | We present a new order statistics based diversity combining scheme (OSDC) for combining a set of independently fading signal amplitudes. The OSDC orders all the received signal amplitudes and uses only the two strongest signals in the combining process. The decision as to whether to use only the strongest or both the strongest and the next strongest is mane depending on the relative strengths of these two highest order statistics. Signal-to-noise ratio performance of the new scheme is compared with that of the traditional schemes such as, selection combining, maximal ratio combining, equal gain combining, and a second order selection combining (SC2), for three channels, namely Rayleigh, Nakagami and exponential. The results show that OSDC performs as well as SC2. | deu_Latn | 13,326 |
Crimp in Wool: Cortical Segmentation and Tensile Properties of Well-Crimped and Abnormally Crimped Fibres of Merino Wool | Poorly crimped (or doggy) fibres, produced by follicles with hyperplasia of the outer root sheath tissue, have greater proportions of paracortex than adjacent well-crimped fibres. Associated with this increase in paracortex is an increase in strength, as indicated by significant increases in the stresses in wet poorly crimped fibres at the turnover and breaking points on the stress-strain curve. Use of the stronger mechanical properties of doggy fibres as a means of distinguishing such fibres from the poorly crimped fibres in steely wool, produced by sheep on a copper-deficient diet, is proposed. | In this paper, we investigate the performance of the Sub-carrier Multiplexed-Free Space Optics (SCM-FSO) for transmitting Code Division Multiple Access (CDMA) signals in terms of Carrier-to-Noise-plus-Interference Ratio (CNIR) and Bit Error Rate (BER), under Gamma-Gamma turbulent FSO channel. We propose an analytical model for optimization of the SCM-FSO link and a closed-form BER expression taking into account the nonlinear effects of the SCM optical link as well as the strong atmospheric turbulence of the FSO channel. We emphasize how the choice of optimal optical modulation index (OMI) can increase the received CNIR and also its dependency on the attenuation of the FSO channel. We then discuss the effect of atmospheric turbulence on the received BER. It is shown that, for a high quality CDMA signals reception over the SCM-FSO system, the link has to be engineered to perform optimally in terms of received optical power, number of carriers and OMI. | eng_Latn | 13,327 |
An Application Research on Adding Windows Technology in NC-OFDM Systems | This paper discusses the inherent mechanism of adding windows technology and its application in NC-OFDM systems,for two windows and different roll-off factors,the simulation is conducted to compare the performance of the power spectrum out-of-band attenuation of the NC-OFDM signals.The results indicate that the attenuation is improved due to the added windows;meanwhile,the signals out-of-band attenuation is also different because of various windows and roll-off factors. | : ::: Deborah Winslow is contributing editor of Gateway to NSF, the National Science Foundation column in Anthropology News. | eng_Latn | 13,328 |
Fiber Array Unit with Reduced Clad Fibers for High-Density Fiber-Chip Coupling | We discuss the integration of G.657-compatible reduced-clad bend-insensitive (RCBI) fibers into two-dimensional fiber array units (FAUs) and into FAUs incorporating 90-degree bends to enable high-density and small form-factor fiber-chip connectivity solutions. | In this paper, we consider utilizing the space-time codes in the wideband CDMA system. We assume that there are multiple resolvable paths in the frequency selective fading channel. Analytical results show that in addition to spatial diversity, another diversity gain called multipath diversity is achievable. Performance criterion for full space multipath diversity gain is analyzed. We consider both the case that the receiver has the ideal channel state information and the case that there are errors in the channel state information available to the receiver. A RAKE receiver is used in the CDMA system to gain the multipath diversity. We derive the generalized RAKE receiver structure for the space-time block coding (STBC) coded wideband CDMA systems. The simulation results demonstrate the additional gain guaranteed by the multipath diversity. | eng_Latn | 13,329 |
Tunable delta-sigma modulator for agile all-digital transmitters | Fully digital transmitters have been thoroughly explored over the last few years to develop a novel type of agile, reconfigurable, multi-band, multi-standard and highly-efficient transmitters. However, with regard to agility and reconfigurability, current state-of-the-art approaches are still very restrictive. This paper proposes a new architecture based on a tunable delta-sigma modulator suitable for designing RF fully digital transmitters either in single-carrier or in dual-carrier scenarios. A 2-path polyphase decomposition was also developed to optimize some figures of merit, such as SNR and EVM, and to demonstrate the scalability of this type of modulator. This novel architecture has been successfully implemented and validated on an FPGA-based transmitter for single- and dual-carrier scenarios. | This paper addresses the problem of channel and propagation delay estimation in asynchronous DS/CDMA systems. We consider the uplink connection in DS/CDMA with long spreading codes. The MIMO stochastic gradient algorithm proposed in [6] is estimating a linear combination of the channel impulse responses and the propagation delays. This estimate suffices for the equalization purposes. The propagation delays are estimated with a simple matching scheme. | eng_Latn | 13,330 |
Urofacial (Ochoa) Syndrome - A Case Report | Urofacial (Ochoa) syndrome is a very rare autosomal recessive disorder characterized by a peculiar inverted facial expression, mainly when smiling or crying and urinary abnormalities. A 5-year-old boy, born of non- consanguineous marriage presented with characteristic facial grimace, enuresis, constipation and delayed milestones. An evaluation of GTG-banded metaphases revealed a normal karyotype with a paternally inherited variant chromosome 14 (14ps+). However, his father showed a normal phenotype. This is the first report of Ochoa syndrome from India. | The fifth generation (5G) wireless network faces unprecedented massive concurrent random access requests in uplink (UL) contention-based (CB) transmission. In this paper, a non-orthogonal coded access (NOCA) UL transmission in combination with parallel interference cancellation (PIC) based reception scheme at base station is investigated. Non-orthonormal code generated by Zadoff-Chu (ZC) sequences is used to spread the data bits over orthogonal frequency division multiple (OFDM) symbols. It is shown through both link level and system level simulations that in dense urban scenario NOCA-PIC scheme is capable of working in highly overloaded system conditions. It can support more than 4 times concurrent random access number compared with OFDM based CB transmission. | kor_Hang | 13,331 |
Power Controlled DS-CDMA Uplink with a HD-PIC Receiver | A hard-decision parallel interference cancellation receiver suitable for closed-loop power controlled CDMA uplink is introduced. Receiver algorithms for cancellation and SIR estimation are presented. A simple model for inter-cell interference is proposed to gain insight into the detector performance in cellular CDMA networks. Multiantenna diversity reception with maximal-ratio combining is employed in reception. The receiver performance is evaluated in fading multipath environments with simulations. Performance gains with regard to the conventional receiver are found in both pico- and macro-cellular environments. Gain from cancellation is found to be larger in more rapidly fading vehicular environments, where power control has less effect on the fluctuation of the received power. Results suggest the utilisation of the near-far robustness of the HD-PIC in power control algorithm design. | Systems on Chip performances in terms of speed and power dissipation is becoming dominated by communication between the cores. To overcome the limitations of traditional bus architectures, nowadays Network-on-Chip architectures are adopted. The Dynamic Power Management architecture and algorithm and Network-on-Chip topology and routing algorithms should be selected considering that they both effect in a complex and complementary way the network throughput and power dissipation. This paper presents the analysis of the effect of Dynamic Power Management strategies on Network-on-Chip performances. | eng_Latn | 13,332 |
A simple method for direct compensation for kinematic energy spread using a silicon PSD | Abstract A simple method of compensating for the kinematic energy spread of the particles from a nuclear reaction detected in a silicon PSD is described. The technique relies on a suitable choice of the series resistor for the reaction of interest and the degree of compensation is shown to be equivalent to the first order correction for the acceptance of a magnetic spectrometer. Experimental results using recoil protons, elastically scattered alpha-particles and carbon ions from a heavy ion induced reaction illustrate the practical application and success of the technique. The limit of the compensation for light ions is set by the resistive noise in the ‘energy x position’ signal while for heavy ions the nuclear scattering spread sets the lower limit. | Abstract Optical wireless communication technologies are finding a greater interest and wider attention within the research community of late. In this paper, we investigate the performance of a free space optical communication system over a generic propagation model called M -distributed channel in the presence of atmospheric turbulence. We analyzed a Subcarrier intensity-modulated free-space optical (SIM-FSO) communication system using DPSK and closed form expressions are derived using Meijer G function for bit error rate, channel capacity and outage probability for M -distribution. | eng_Latn | 13,333 |
Scattering of Gaussian beam by a ferrite cylinder | The scattering of a Gaussian beam by a ferrite cylinder is analyzed using two methods. The spatial pictures in the amplitude of the total Gaussian beam near the cylinder resulting from the two methods are both clarified and compared. The scattering by a ferrite cylinder coating a dielectric sleeve is also presented. | In traditional CP-OFDM technology exist has two drawbacks,i.e.,the adding of cyclic prefix would result in low spectrum efficiency and it is sensitive to the Doppler frequency shift.This paper principally discusses the issue of pulse shaping filter for GFDM(generalized frequency division multiplex) system.With the suitable arrangement,GFDM system could match the channel propagation against the inter-symbol interference and inter-carrier interference.Finally,PAPR(peak-to-average-power-ratio) for GFDM system is exoounded,and the bit error ratio performance in presence of HPA(high-power amplifier) also analyzed. | eng_Latn | 13,334 |
Reconfigurable optical inter-channel interference compensation of 20/25-Gbaud QPSK signals using nonlinear wave mixing | A reconfigurable optical inter-channel interference compensation method without channel spacing estimation and relative time delay calibration is proposed for a high density multi-carrier transmission system. Experiments demonstrate the effectiveness for both 20/25-Gbaud dual-carrier QPSK systems with different channel spacing conditions. | Problems associated with the modelling and calculation of quasi-steady-state postfault regimes are considered for abrupt power unbalances. A program permitting calculation of quasi-steady-state postfault regimes with allowance for frequency dynamics and the investigation of their stability is described. Results of calculations based on this program are compared with experiments using an electrodynamic model. It is shown that allowance must be made for frequency dynamics in the analysis of postfault regimes. 9 refs. | eng_Latn | 13,335 |
Case study: the design of a mixed-signal global positioning system receiver using multichip module packaging | In a collaborative project, the Mayo Foundation and Motorola have developed a fully functional miniaturized global positioning system (GPS) receiver using laminated multichip modules (MCM-L). This paper presents the system requirements, design constraints, substrate selection criteria and description, design approach, assembly, and test of a fully operational GPS receiver to describe the generic mixed-signal design techniques used during the development cycle. | This paper addresses the problem of channel and propagation delay estimation in asynchronous DS/CDMA systems. We consider the uplink connection in DS/CDMA with long spreading codes. The MIMO stochastic gradient algorithm proposed in [6] is estimating a linear combination of the channel impulse responses and the propagation delays. This estimate suffices for the equalization purposes. The propagation delays are estimated with a simple matching scheme. | eng_Latn | 13,336 |
Research on and Design of Wireless Sensor Network Gateway Based on 6LoWPAN | IPv6 is combined with low power consumption wireless personal area network based on IEEE 802.15.4 to build 6LoWPAN network which meets the future development of the internet of things and has far-reaching significance.In this paper,we propose a gateway solution for wireless sensor network based on 6LoWPAN,which can realize the wireless sensor network based on 6LoWPAN and IPv6 network interconnection.In addition,we relate and analyze the hardware and software design of the gateway.Finally,we set up a test network,and test the connectivity of the end-to-end network,change of the delay,round trip times,packets loss rate,and the throughput of the packets.Then we make briefly performance analysis of the network.The experiment shows that the gateway can realize the wireless sensor network based on 6LoWPAN and IPv6 network interconnection,and it can run in actual network environment. | In this paper, we consider utilizing the space-time codes in the wideband CDMA system. We assume that there are multiple resolvable paths in the frequency selective fading channel. Analytical results show that in addition to spatial diversity, another diversity gain called multipath diversity is achievable. Performance criterion for full space multipath diversity gain is analyzed. We consider both the case that the receiver has the ideal channel state information and the case that there are errors in the channel state information available to the receiver. A RAKE receiver is used in the CDMA system to gain the multipath diversity. We derive the generalized RAKE receiver structure for the space-time block coding (STBC) coded wideband CDMA systems. The simulation results demonstrate the additional gain guaranteed by the multipath diversity. | eng_Latn | 13,337 |
EFFECT OF ADAPTIVE MODULATION AND ERROR CORRECTION ON MULTI-BAND OFDM-MIMO SYSTEM | We have devised a new system for forming the antenna beam in a com- bined OFDM and MIMO scheme. In this scheme, the OFDM signal is divided among multiple bands, and the divided signals are transmit- ted on an appropriate beam of each sub-band. In this paper, We have described the system configuration of the proposed multi-band OFDM- MIMO scheme for use over multipath wireless channels. And, we have discussed the performance of adaptive modulation and error correction of the system. | We show <-50 dB AM-to-PM conversion over a wide photocurrent range in MUTC photodiodes. By controlling the AM-to-PM coefficient minimum, we generate 15 dBm microwave power with 60 dB AM rejection onto the microwave phase. | yue_Hant | 13,338 |
Thermal throttling using RF diversity | In certain aspects, a method for communications comprises outputting a first portion of a signal to a first one of a plurality of RF modules for transmission, determining a throughput of the first one of the plurality of RF modules during thermal throttling of the first one of the plurality of RF modules, comparing the determined throughput of the first one of the plurality of RF modules with a throughput of a second one of the plurality of RF modules, and outputting a second portion of the signal to the second one of the plurality of RF modules for transmission if the throughput of the second one of the plurality of RF modules is higher than the determined throughput of the first one of the plurality of RF modules. | In an earlier paper by the author the problem of determining the optimum symmetrical weighting factors for a video MTI radar was discussed. This paper extends this work so as to remove the symmetrical restriction from the problem. In addition, for a staggered pulse system, optimum times of transmission are determined. In the earlier paper a global solution to the restricted optimization problem was achieved. In this paper only a locally optimum solution is achieved for the more general problem. | eng_Latn | 13,339 |
Full-random hopped-frequency waveform design and processing | For the high frequency radar system,it is difficult to find a clear wideband for operation.In order to obtain a high range resolution,transmitting/receiving waveform with discontinuous frequency bands is proposed.However,spectrum discontinuity of waveform will result in high range sidelobes.The full-random hopped-frequency waveform for sidelobe suppression is investigated.By controlling the occurrence probability of different frequencies,full-random hopped-frequency waveform can achieve a low sidelobe.Statistical characteristics of the autocorrelation function are analyzed,and the waveform design methods on both continuous and discontinuous band are also given. | This work describes a method for providing robustness to errors from a binary symmetric channel for the SPIHT image compression. The source rate and channel rate are jointly optimized by a stream of fixed-size channel packets. Punctured turbo codes are used for the channel coding, providing stronger error protection than previously available codes. We use a subset of the puncturing patterns that are well chosen and that leads to the best source rate. The rate allocation scheme presented obtains all necessary information from the SPIHT encoder, and does not require image decompression. | eng_Latn | 13,340 |
Characterization of electroactive Langmuir-Blodgett monolayers of (ferrocenylmethyl)dimethyloctadecylammonium sulfate at gold and air/water interfaces | Des couches monomoleculaires organisees d'hexafluorophosphate de (ferrocenylmethyl) dimethyloctadecylammonium sont transferres via la methode de Langmuir Blodgett sur des electrodes hydrophiles d'or et etudiees | A DFT spread Generalized Multi-Carrier (GMC) based Frequency Division Multiple Access (FDMA) scheme, i.e. DFT-S-GMC, is proposed for uplink transmission of wideband mobile communication systems. The scheme achieves spreading gains in the frequency-domain by Discrete Fourier Transform (DFT), and the Frequency Division Multiplexing (FDM) and FDMA by Inverse Filter-Bank Transform (IFBT). By theoretical analysis and simulation results, it is shown that the proposed scheme has good Peak-to-Average Power Ratio (PAPR) performance and is more robust to the Multi-Access Interference (MAI) than the existed main stream uplink schemes, e.g. OFDMA and DFT-S-OFDMA scheme. | eng_Latn | 13,341 |
Using Gauss pseudospectral method to optimize aeroassisted orbit transfer | The Gauss pseudospectral method was used to solve the coplanar aeroassisted orbit transfer from High Earth Orbit to Low Earth Orbit (HEO-LEO). Using above method the optimal solution was obtained by changing the optimal-fuel index to the suitable atmospherical inlet and outlet conditions and taking the shortest flight time in atmosphere as the optimal index. Compared with Hohmann orbit transfer, the aeroassisted orbit transfer reduces fuel consumption obviously. Meanwhile, it is proved that the Gauss pseudospectral method is effective to solve the optimal orbit transfer problem. | A high-speed data transmission system based on TMS320C6455 is designed.The input and output interface are separately USB and PCI.The control module is FPGA.The most advantage of the designed system is the powerful signal processing capability,which can be used for the realization of various image processing algorithms.For example,aimed to reduce the requirement of storage,a image coding algorithm(SPIHT) is implemented.At last,the tested results of the system are given.It can be found that the designed system can be used in various data transmission systems and image processing algorithm verification systems. | eng_Latn | 13,342 |
Improvement of mucosal pathology of the sinuses after exposure to sulfur dioxide by nebulization of S-carboxymethylcysteine. | Since s-carboxymethylcysteine (S-CMC) can directly enhance the ciliary activity in the maxillary sinus mucosa of patients with chronic sinusitis in the absence of significant organic changes of ciliated cells, the nebulization therapy using this medicine might be more effective in the treatment of chronic sinusitis than oral administration of the medicine. The safety of using 0.5–10% of S-SMC as a medicine for nebulization has been experimentally established. The present study was designed to experimentally examine the effectiveness of nebulization using 0.5–10% of S-CMC solution in the treatment of experimental chronic sinusitis in rabbits recurrently exposed to 20 ppm of sulfur dioxide. Thirty-three healthy rabbits were used; 3 of them were used as controls. The remaining 30 were exposed to 20 ppm of sulfur dioxide for 4 h a day for 4 successive weeks. Twelve animals were not treated with any medication during the post-exposure period, and sacrificed at 24 h or 15 days after completion of the final expo... | In this paper, we investigate the performance of the Sub-carrier Multiplexed-Free Space Optics (SCM-FSO) for transmitting Code Division Multiple Access (CDMA) signals in terms of Carrier-to-Noise-plus-Interference Ratio (CNIR) and Bit Error Rate (BER), under Gamma-Gamma turbulent FSO channel. We propose an analytical model for optimization of the SCM-FSO link and a closed-form BER expression taking into account the nonlinear effects of the SCM optical link as well as the strong atmospheric turbulence of the FSO channel. We emphasize how the choice of optimal optical modulation index (OMI) can increase the received CNIR and also its dependency on the attenuation of the FSO channel. We then discuss the effect of atmospheric turbulence on the received BER. It is shown that, for a high quality CDMA signals reception over the SCM-FSO system, the link has to be engineered to perform optimally in terms of received optical power, number of carriers and OMI. | eng_Latn | 13,343 |
A 400 Gb/s WDM receiver using a low loss silicon nitride AWG integrated with hybrid silicon photodetectors | A heterogeneously integrated WDM receiver based on an AWG demultiplexer and hybrid silicon/InGaAs detectors is presented in a novel platform that combines hybrid silicon components with ultra-low loss silicon nitride waveguides. | A best and efficiently to provide a system and method capable of setting up a resource by the receiving device and the wireless network. A transmitting device several QoS parameters negotiated, signaling to the receiving devices of the session during the session setup procedure. Guaranteed bit rate, maximum bit rate, and transfer delay is signaled to the receiving device. New session description protocol attribute defined for QoS parameters described above, which are executed by the Session Initiation Protocol message. The receiving device uses these SDP attributes may be in the PDP activation, to negotiate wireless network and QoS parameters itself. The receiving device uses these parameters to resources such as jitter buffer for voice and video can be set accordingly. .FIELD 4 | eng_Latn | 13,344 |
Spectral efficiency improvement techniques for nonlinearly amplified mobile radio systems | A study is reported of 'double-jump' Nyquist channel filters which lead to reduced spectral spreading and an important bit error rate (BER) performance in nonlinearly amplified (NLA) mobile radio systems. In linearly amplified systems the filter retains the intersymbol-interference free properties of Nyquist filters and has the advantage of lower overshoot than the conventional raised cosine (RCS) filters. This reduced overshoot power (ROP) filter leads to a 1 dB system gain over conventional RCS filtered 16-QAM systems in NLA channels. > | The design of multivariable systems can be approached with many different design objectives. An appealing approach from a mathematical point of view is to describe the dynamics of plant and compensator in state-spaco form, transform the resulting augmented system into a problem involving a system performance index such as pole assignment, and apply optimization techniques to choose compensator parameters. This paper develops a methodology whereby exact or partial pole assignment under variations of plant characteristics is incorporated into the system performance index. Through calculations of the gradients of the performance index with respect to compensator parameters, one is able to apply derivative optimization methods to the design problem. Examples are provided to illustrate the design methodology. | eng_Latn | 13,345 |
A Flexible LDPC Decoder Architecture Supporting TPMP and TDMP Decoding Algorithms | In this paper a programmable and area-efficient decoder architecture supporting two decoding algorithms for Block-LDPC codes is presented. The novel decoder can be configured to decode in either TPMP or TDMP decoding mode according to different Block-LDPC codes, essentially combining the advantages of two decoding algorithms. With a regular and scalable data-path, a Reconfigurable Serial Processing Engine (RSPE) is proposed to achieve area efficiency. To verify our proposed architecture, a flexible LDPC decoder fully compliant to IEEE 802.16e applications is implemented on a 130nm 1P8M CMOS technology with a total area of 6.3mm2 and maximum operating frequency of 250MHz. The chip dissipates 592mW when operates at 250MHz frequency and 1.2V supply. | In this article, perspective using of the laser deposition method for manufacture details from the titanium alloy VT20 is considered. Dependence on a structure of the fractional composition is shown. Study of the structure and properties of parts, which were produced by DLD technology using different modes and under different conditions. | kor_Hang | 13,346 |
A broadband 480-GHz passive frequency doubler in 65-nm bulk CMOS with 0.23mW output power | A passive 480-GHz frequency doubler based on accumulation-mode MOS varactor in CMOS process is reported. Using a compact partially-coupled ring structure, the doubler achieves a simultaneous broadband matching for fundamental and 2nd-harmonic signals. With optimized gate length and oxide thickness, the MOS varactor achieves a dynamic cutoff frequency of 870GHz while sustaining large voltage swing for high power generation. At 480-GHz output frequency, the doubler has a measured minimum conversion loss of 14.3dB and an unsaturated output power of 0.23mW. The simulated 3-dB output bandwidth is 70GHz (14.6%). The doubler is fabricated using 65-nm low power bulk CMOS technology and consumes zero DC power. | In this paper an FM detector capable of suppressing the degradation in receiver performance due to the presence of an interfering signal is presented. Optimum receiver structures based on maximum-aposteriori estimation procedures are first derived and then a practical demodulator based on the optimum receivers is examined. The receiver consists of two phase-locked loops (PLL) interconnected in a manner to permit one PLL to lock onto and track the Stronger received FM signal while the other loop tracks the weaker of the two received FM signals. The detector has the capability of demodulating both the desired received FM as well as the interferer even for the case when both signals are co-channel. Experimental results demonstrating such capability even in the presence of strong input Gaussian noise are presented. | eng_Latn | 13,347 |
Detection of osmium by flame atomic emission spectrometry after extraction as osmium tetroxide into MIBK | Abstract A selective method for the detection of osmium by flame atomic emission spectrometry is described. The method is based on extracting osmium tetroxide into MIBK, at pH 2.1–9.5, and aspirating the extract into a nitrous oxide-acetylene flame. By this procedure the effect of common interferences in atomic emission spectrometric determination of osmium has been eliminated or minimized. | In this study, the authors propose an optical microwave (MW) radio-over-fibre system in which an integrated dual-parallel Mach-Zehnder modulator (DP-MZM) is biased at the maximum transmission biasing point. A single drive Mach-Zehnder modulator, in series with the DP-MZM, is used to modulate the 1 GHz radio frequency data onto the optical carrier. They characterise the efficiency of the practical system in terms of power penalty and error vector magnitude. Two modulation schemes are investigated, namely binary phase shift keying (BPSK) and quadrature phase shift keying (QPSK) over fibre spans of 10 and 25 km of standard single mode fibre. The results show that the second-order sideband of MW has the potential to provide error free transmission for BPSK and QPSK. The error free communication system is achieved for BPSK at 10 and 25 km fibre spans at optical launch power (OLP) of 7 dBm, whereas for QPSK, the OLP is ~11 and ~12 dBm for 10 and 25 km fibre spans, respectively. | eng_Latn | 13,348 |
Synchronous CDMA technique for fiber-optic LANs with folded dual bus topology | The synchronization in the code-division multiple-access (CDMA) fiber-optic networks reduces interchannel interference, permits larger number of stations, and gives higher throughput. In the star topology proposed, very strict synchronization of transmitters and equalization of propagation delays over various paths in the network is achieved since a single optical source is used for the whole network, and all the signals follow that same path around the network. Other advantages are that the operation mode of the optical source is pulsed, not continuous-wave, and the attenuation variations among interfering signals are low. The major disadvantage of the proposed system is in its stricter power constraints. This problem can be alleviated by the insertion of optical amplifiers when the number of stations outgrows the limits of the basic network. > | In this paper,property and characteristic of Optim fiber are analysed.By developing of cashmere/Optim blended knitting yarn,it discusses some questions in manufacture practice of recombing,fore spinning and spinning process,and provides some measures to solve these questions.This article discusses the design of the technological parameter and the question of cashmere blending.This development provides some references on developing Optim fine fabric. | eng_Latn | 13,349 |
A highly linear SiGe double-balanced mixer for 77 GHz automotive radar applications | An active double-balanced mixer for automotive applications in the 77 GHz range is presented. The circuit includes on-chip baluns both at the RF and the LO port. The mixer was designed and fabricated in a 200 GHz f/sub T/ SiGe:C bipolar technology. The chip was characterized by on-wafer measurements. At 77 GHz, the conversion gain of the mixer is 11.5 dB. The single sideband noise figure at 77 GHz is 15.8 dB. The input-referred 1 dB compression point at 75 GHz is -0.3 dBm. Measurements across the wafer verified that this mixer circuit is robust against wafer inhomogeneities. The size of the chip is 700/spl mu/m /spl times/ 900/spl mu/m. The circuit was designed for a supply voltage of 5.5 V and draws 75 mA. | In this paper, we consider utilizing the space-time codes in the wideband CDMA system. We assume that there are multiple resolvable paths in the frequency selective fading channel. Analytical results show that in addition to spatial diversity, another diversity gain called multipath diversity is achievable. Performance criterion for full space multipath diversity gain is analyzed. We consider both the case that the receiver has the ideal channel state information and the case that there are errors in the channel state information available to the receiver. A RAKE receiver is used in the CDMA system to gain the multipath diversity. We derive the generalized RAKE receiver structure for the space-time block coding (STBC) coded wideband CDMA systems. The simulation results demonstrate the additional gain guaranteed by the multipath diversity. | eng_Latn | 13,350 |
An efficient decoupling network for microstrip phased array antenna | An efficient decoupling network for microstrip phased array is proposed. It can provide an indirect coupling with controlled magnitude and phase which can be used to cancel the direct coupling caused by space waves and surfaces waves between adjacent elements. Due to the reduced mutual coupling, the simulated active reflection coefficient remains lower than −15 dB in the scan range (0–70°). | In this paper, we consider utilizing the space-time codes in the wideband CDMA system. We assume that there are multiple resolvable paths in the frequency selective fading channel. Analytical results show that in addition to spatial diversity, another diversity gain called multipath diversity is achievable. Performance criterion for full space multipath diversity gain is analyzed. We consider both the case that the receiver has the ideal channel state information and the case that there are errors in the channel state information available to the receiver. A RAKE receiver is used in the CDMA system to gain the multipath diversity. We derive the generalized RAKE receiver structure for the space-time block coding (STBC) coded wideband CDMA systems. The simulation results demonstrate the additional gain guaranteed by the multipath diversity. | eng_Latn | 13,351 |
Performance of multi-user MIMO OFDM system with adaptive modulation and coding for wireless communications | As the demand of high quality service in next generation wireless communication systems, a high performance of data transmission requires an increase of spectrum efficiency and an improvement of error performance in wireless communication systems. In this paper, we propose a multi-user multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) system with adaptive modulation and coding to improve system capacity with maintaining good error performance. The results of computer simulation show the improvement of system capacity in Rayleigh fading channel. | In the pilot study on the treatment of polyvinyl chloride centrifugal mother liquid wastewater by using a combination of MBR and RO,the removal efficiency of organics and suspending solid together with the capability to resist the impact of the system were researched.The changes of the biological phase in the MBR and the membrane fouling of both membranes were observed.The experiment results show that the total removal efficiency of COD was over 95%,the effluent less than 40 mg/L can meet the requirement of wastewater discharge standard.Furthermore,the effluent of the MBR can reach the polymerization reuse water standard with a water recovery more than 70% after being treated by antiosmosis,Ion exchange or EDI.Film properties are in a good state during the experiment. | eng_Latn | 13,352 |
Performance enhancement of an optical interconnect using short pulses from a modelocked diode laser | Summary form only given. We have demonstrated a short-pulse optical interconnect that uses a practical, high-repetition-rate modelocked source. BER measurements show that operation with short pulses improves system performance by providing a receiver sensitivity enhancement of 3.3 dB. The link has additional benefits related to timing issues and latency reduction. | In this paper a programmable and area-efficient decoder architecture supporting two decoding algorithms for Block-LDPC codes is presented. The novel decoder can be configured to decode in either TPMP or TDMP decoding mode according to different Block-LDPC codes, essentially combining the advantages of two decoding algorithms. With a regular and scalable data-path, a Reconfigurable Serial Processing Engine (RSPE) is proposed to achieve area efficiency. To verify our proposed architecture, a flexible LDPC decoder fully compliant to IEEE 802.16e applications is implemented on a 130nm 1P8M CMOS technology with a total area of 6.3mm2 and maximum operating frequency of 250MHz. The chip dissipates 592mW when operates at 250MHz frequency and 1.2V supply. | eng_Latn | 13,353 |
Adaptive code allocation for interference management on the downlink of DS-CDMA systems | A new technique based on adaptive code-to-user allocation for interference management on the downlink of BPSK based TDD DS-CDMA systems is presented. The principle of the proposed technique is to exploit the dependency of multiple access interference on the instantaneous symbol values of the active users. The objective is to adaptively allocate the available spreading sequences to users on a symbol-by-symbol basis to optimize the decision variables at the downlink receivers. The presented simulations show an overall system BER performance improvement of more than an order of a magnitude with the proposed technique while the adaptation overhead is kept less than 10% of the available bandwidth. | A new approach was proposed for the DOA joint estimation of signal,and the algorithms are based on ESPRIT and two or more array data correlation matrix.It estimated simultaneously the DOA of bis/multistatic.The algorithms estimated parameter are auto paired.The CRLB of the DOA stimation was also derived.The simulating results show that the new methods are equally effective. | eng_Latn | 13,354 |
Evaluation of the Response of Concurrent High Dose Rate Intracavitary Brachytherapy with External Beam Radiotherapy in Management of Early Stage Carcinoma Cervix | Objectives ::: To evaluate local disease control and early complications of concomitant brachytherapy with external beam-radiotherapy in early stage carcinoma cervix. | As the 3GPP Long Term Evolution (LTE) systems mature and more LTE mobiles become ubiquitous the Random Access Channel (RACH) will experience higher load. Understanding RACH capacity is of high importance for the 4G system planners. Capacity of the LTE RACH was analyzed in the past under the assumption of the ideal receiver with zero missed detection probability. In this work we assume realistic PRACH receiver under the assumption of AWGN channel which is specified as one of the test cases in the standard. We derive the expression for the preamble detection probability when r UEs are transmitting. Using this quantity we compute normalized RACH throughput for a single cell. We experiment with different parameters to illustrate their impact on RACH capacity. We show that the Gaussian channel can degrade ideal receiver capacity significantly (13%-66%) depending on the choice of system parameters. | eng_Latn | 13,355 |
Space-time coded wideband CDMA systems | In this paper, we consider utilizing the space-time codes in the wideband CDMA system. We assume that there are multiple resolvable paths in the frequency selective fading channel. Analytical results show that in addition to spatial diversity, another diversity gain called multipath diversity is achievable. Performance criterion for full space multipath diversity gain is analyzed. We consider both the case that the receiver has the ideal channel state information and the case that there are errors in the channel state information available to the receiver. A RAKE receiver is used in the CDMA system to gain the multipath diversity. We derive the generalized RAKE receiver structure for the space-time block coding (STBC) coded wideband CDMA systems. The simulation results demonstrate the additional gain guaranteed by the multipath diversity. | In this paper, the GMT–PO hybrid method accompanied by the iterative technique is applied successfully to calculate 3-D numerical diffraction coefficients (3-D NDC) of the irregular circular-cylinder edge. The computed RCS of the circular cylinder with 3-D NDC of the irregular edge is in good agreement with the measured data from the reference. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 31: 108–110, 2001. | eng_Latn | 13,356 |
Voice quality of digital wireless networks under fading channel conditions | Telephone calls will increasingly involve a large number of multi-link circuits incorporating a variety of speech coding devices. This paper presents the results of a subjective evaluation which makes the first attempt to estimate voice quality of international connections when different wireless coding methods are used in the presence of channel-impairments. The methods evaluated included: 8 kb/s VSELP, 13 kb/s RPE-LTP, 32 kb/s ADPCM, and 16 kb/s LD-CELP. From this it was concluded that when wireless cellular links are in degraded state, end-to-end network performance is unlikely to meet transmission performance standards for fixed-wireline connections. Further, fixed-radio links, which are assumed to be provisioning the international part of the connection, do not appear to be contributing to the reduced performance. | This paper studies the mutual interference of wideband and narrowband CDMA in the mobile satellite communication system of narrowband CDMA overlaying on wideband CDMA,then it offers the best spectrum allocation of the two kinds of signals,and we find that the capacity of satellite mobile system will increase dramatically in our spectrum allocation. | eng_Latn | 13,357 |
Apparatus and method for deploying efficient broadcast multicast services in a wireless network, system using the same and message structure therefor | A message transmitted from a mobile station to a base station in a wireless network providing broadcast multicast services includes a quality of service feature associated with multicast data transmissions broadcast from the base station to a plurality of mobile stations to provide real-time feedback to the base station and allow the mobile station to release or reject the broadcast multicast service. | In an earlier paper by the author the problem of determining the optimum symmetrical weighting factors for a video MTI radar was discussed. This paper extends this work so as to remove the symmetrical restriction from the problem. In addition, for a staggered pulse system, optimum times of transmission are determined. In the earlier paper a global solution to the restricted optimization problem was achieved. In this paper only a locally optimum solution is achieved for the more general problem. | eng_Latn | 13,358 |
A method for managing dissolved oxygen concentration during live hauling of channel catfish | After experiencing difficulty in managing dissolved oxygen levels on several live hauls, a method has been developed for estimating the oxygen flow rate needed to sustain live channel catfish Ictalurus punctatus during transport. The mathematical model described in this paper provides aquaculturists, fish farmers, and fish haulers with an analytical method for estimating the oxygen flow rate needed to sustain a given biomass of channel catfish I. punctatus during transport. Based on peer-reviewed scientific literature, readily obtained data, and program in Microsoft | Abstract Optical wireless communication technologies are finding a greater interest and wider attention within the research community of late. In this paper, we investigate the performance of a free space optical communication system over a generic propagation model called M -distributed channel in the presence of atmospheric turbulence. We analyzed a Subcarrier intensity-modulated free-space optical (SIM-FSO) communication system using DPSK and closed form expressions are derived using Meijer G function for bit error rate, channel capacity and outage probability for M -distribution. | eng_Latn | 13,359 |
Nonsteroidal anti-inflammatory drugs can lower amyloidogenic Abeta42 by inhibiting Rho. | A subset of nonsteroidal anti-inflammatory drugs (NSAIDs) has been shown to preferentially reduce the secretion of the highly amyloidogenic, 42-residue amyloid-beta peptide Abeta42. We found that Rho and its effector, Rho-associated kinase, preferentially regulated the amount of Abeta42 produced in vitro and that only those NSAIDs effective as Rho inhibitors lowered Abeta42. Administration of Y-27632, a selective Rock inhibitor, also preferentially lowered brain levels of Abeta42 in a transgenic mouse model of Alzheimer's disease. Thus, the Rho-Rock pathway may regulate amyloid precursor protein processing, and a subset of NSAIDs can reduce Abeta42 through inhibition of Rho activity. | The transmission performance of single-sideband alternate mark inversion return-to-zero (SSB-AMI-RZ) formats, with duty-cycles of 15%, 30% and 50%, in long-haul 40 Gbit/s/channel ultra dense WDM systems with 50 GHz of channel spacing is assessed through systematic numerical simulation. After optimizing the bandwidths and detuning of optical multiplexer and demultiplexer, the dispersion maps are optimized for each duty-cycle. From these, the tolerances to the in-line residual dispersion (IRD) and total residual dispersion (TRD), and the nonlinear thresholds (NLT) are assessed. It is shown that the different SSB-AMI-RZ formats have high tolerance to linear crosstalk, due to a - 20 dB bandwidth much smaller than the channel spacing, and similar tolerance to IRD. Numerical results indicate that the format with duty-cycle of 15% outperform the others because of its better tolerance to TRD and higher NLT. | eng_Latn | 13,360 |
Theoretical and experimental assessment of nonlinearity mitigation through symbol rate optimization | We investigated the reach increase obtained through non-linearity mitigation by means of transmission symbol rate optimization (SRO). First, we did this theoretically and simulatively. We found that for PM-QPSK systems at full-C-band the reach increase may be substantial, on the order of 10%–25%, with optimum symbol rates on the order of 2-to-6 GBaud. We extended the investigation to PM-16QAM, where we found a qualitatively similar effect, although the potential reach increase is typically only about half that of PM-QPSK. We then set up an experiment to obtain confrmation of the theoretical and simulative predictions. We demonstrated a reach increase of 11% in a 19-channel, 128 Gbit/s per channel, PM-QPSK experiment, when going from single-carrier to multi-subcarrier (up to 16 subcarriers per channel) transmission. The experiment reached 14,100 km over PSCF, with 110 km spans and EDFA-only amplifcation. The results matched well the EGN model predictions. | In this paper,node power of compensation method is obtained with two 8 rank matrix.Two line outage load flow is obtained by Newton. Newton load flow for normal state is used,so efficiency and accuracy of line outage analysis are improved. | eng_Latn | 13,361 |
Impact of AWGN Channel on LTE RACH Throughput | As the 3GPP Long Term Evolution (LTE) systems mature and more LTE mobiles become ubiquitous the Random Access Channel (RACH) will experience higher load. Understanding RACH capacity is of high importance for the 4G system planners. Capacity of the LTE RACH was analyzed in the past under the assumption of the ideal receiver with zero missed detection probability. In this work we assume realistic PRACH receiver under the assumption of AWGN channel which is specified as one of the test cases in the standard. We derive the expression for the preamble detection probability when r UEs are transmitting. Using this quantity we compute normalized RACH throughput for a single cell. We experiment with different parameters to illustrate their impact on RACH capacity. We show that the Gaussian channel can degrade ideal receiver capacity significantly (13%-66%) depending on the choice of system parameters. | Airborne Radar Network has the advantage over Airborne Single Radar in three aspects. Firstly how does it have the performance of countering stealth airplane and of hiding itself; Secondly how does it shorten the time of detecting object; Lastly how does it improve the recognized precision and positioned precision of object. | eng_Latn | 13,362 |
Calibration-free parallel optical interconnection subsystem implemented by a Gbyte/s-array optical transceiver and a one-chip-link LSI | A Gbyte/s-class optical-interconnection subsystem for a parallel computer was developed and it operated stably in a testbed system of the parallel processing machine RWC-1 (Real World Computer-1). Although it consisted of MMF parallel optical modules, data was transmitted over I km because of the deskew operation of a one-chip transmitter and receiver LSIs. Random packets were transmitted without error over 17.5 hours, which corresponded to a BER of 10 -15 . | Abstract The multi-objective optimization of linearized impulsive rendezvous under uncertainty is investigated in this paper. A performance index related to the variances of the terminal state error is defined as the robustness performance index, which is determined by the linear covariance method. The three-objective of the total characteristic velocity, the rendezvous time of flight, and the robustness performance index optimization model based on the Clohessy–Wiltshire (C–W) system is proposed. The multi-objective nondominated sorting genetic algorithm is employed to obtain the Pareto solution set. The optimization results of one homing rendezvous mission are provided, demonstrating that tradeoffs between time of flight, propellant cost and trajectory robustness and several inherent principles of the rendezvous trajectory can be quickly obtained via the current approach. | eng_Latn | 13,363 |
Application of Automatic Binding Release with CAMS Technology in Campus Network Security | To make campus local area network safer,more reliable and more stable,this paper proposes a solution to the problem by combining network switch and server based on an analysis to the potential threats to network security,and a summarization of previous methods about VLAN-partition and binding technology to solve the problem of network security.This solution overcomes the shortage of previous ways and has a good effect on network securit. | We propose a novel machine learning based equalization algorithm for bandwidth-limited IM-DD PON in C-band. 50Gb/s/λ. PAM4 transmission is demonstrated over 20km SSMF using a 10G-class transmitter with 21dB loss budget without amplification. | eng_Latn | 13,364 |
Modulation Schemes and Multiple Access for Impulse Radio | This chapter is dedicated to impulse radio as it is a very prominent form of UWB. Initially, impulse radio (IR) is introduced and generic transceiver architecture for IR is presented. Then, common and custom tailored pulse shapes for impulse radios are discussed. Various IR modulation techniques are presented and their performance is analyzed. To enable multiple accesses, a technique known as time hopping (TH) is introduced and it is integrated into various modulation techniques. Finally, the impact of the various antenna types on the transmitted and received UWB signal is investigated. | We show <-50 dB AM-to-PM conversion over a wide photocurrent range in MUTC photodiodes. By controlling the AM-to-PM coefficient minimum, we generate 15 dBm microwave power with 60 dB AM rejection onto the microwave phase. | eng_Latn | 13,365 |
The performance of LDPC coded frequency hopping system under follower jamming | Follower jamming is a class of jamming way which is very harmful to the frequency hopping system. Low density parity check (LDPC) code is employed in frequency hopping system to combat follower jamming in this paper. The characteristics of follower jamming is introduced firstly, and then the model of LDPC coded FH system is built. The classical Progressive edge growth algorithm is used to construct the parity check matrix of LDPC code, and the sum-product algorithm is applied to obtain the optimum decoding performance. The simulation results show that the proposed system has outstanding anti-jamming capability, which is also compared with the traditional Reed-Solomon (RS) coded system. | A new technique to determine the nonlinearity of high-speed photodiodes is presented. Utilizing a linearized phase-modulated link architecture, we directly measure the photodiode intermodulation distortion. Our results agree with those obtained via a phase-locked laser technique. | eng_Latn | 13,366 |
Dmb receiver and power saving method | The present invention relates to a reduced power consumption of the DMB receiver and a DMB receiver that is based on the Eureka-147 standard method. In particular the present invention with reference to the MCI of the FIC of the transfer frame and extracts the position of the user CU published a service component of the desired broadcast service. And calculates the position within the OFDM symbol including the MSC are the CU. And then transmits the frame of the synchronization channel, FIC, setting the calculated OFDM symbol duration, the operation control section is required to receive the OFDM symbol interval the user desired broadcast service components immediately before the OFDM symbol. Thereafter, by for example a circuit for processing an analog signal, only the operation control section, enabling the operation of the tuner and ADC, there is an effect to reduce the power consumption of the DMB receiver. DMB, CU, OFDM, service elements | We present a preliminary experimental study of the dependence on optical depth of slow and stored light pulses in Rb vapor. In particular, we characterize the efficiency of slow and stored light as a function of Rb density; pulse duration, delay and storage time; and control field intensity. Experimental results are in good qualitative agreement with theoretical calculations based on a simplified three-level model at moderate densities. | eng_Latn | 13,367 |
Continuous Phase Modulation for Digital Video Broadcasting | In this paper, we study the performance of the Digital Video Broadcasting- Terrestrial (DVB-T) system with Continuous Phase Modulation Orthogonal Frequency Division Multiplexing (CPM-OFDM). The proposed structure combines the advantage of mitigating the Peak-to-Average Power Ratio (PAPR) problem in the Power Amplifier (PA) in addition to exploiting the channel frequency diversity and power efficiency of CPM. The proposed CPM-OFDM DVB-T system is implemented with Frequency-Domain Equalization (FDE) to avoid the complexity of the equalization. Two types of frequency domain equalizers are considered and compared for performance evaluation of the system; the Zero-Forcing (ZF) equalizer and the Minimum Mean Square Error (MMSE) equalizer. Simulation results show that the performance of the CPM-OFDM DVB-T system with multi-path fading is better than its performance with single-path fading. | Sony ICX 259AL CCD matrices were irradiated by proton and neutron beams of a synchrocyclotron of the Petersburg Nuclear Physics Institute. The data on production cross sections, as well as the spatial and time distributions of pixels of the irradiated matrices with high dark current, are presented. The experimental data are compared with the calculation results. | eng_Latn | 13,368 |
OBSTACLE DETECTION SYSTEMS ALONG ROADSIDES USING MILLIMETER-WAVE FM-CW RADAR | This paper describes a millimeter wave obstacle detection system which can be installed along on a roadside environment and has a detection algorithm for minimizing background noise. | The present invention relates to a reduced power consumption of the DMB receiver and a DMB receiver that is based on the Eureka-147 standard method. In particular the present invention with reference to the MCI of the FIC of the transfer frame and extracts the position of the user CU published a service component of the desired broadcast service. And calculates the position within the OFDM symbol including the MSC are the CU. And then transmits the frame of the synchronization channel, FIC, setting the calculated OFDM symbol duration, the operation control section is required to receive the OFDM symbol interval the user desired broadcast service components immediately before the OFDM symbol. Thereafter, by for example a circuit for processing an analog signal, only the operation control section, enabling the operation of the tuner and ADC, there is an effect to reduce the power consumption of the DMB receiver. DMB, CU, OFDM, service elements | yue_Hant | 13,369 |
Muon spin rotation experiments in α-Fe2O3 and Cr2O3 | Abstract The behaviour of the stopped muons in the isostructural antiferromagnetic insulators α-Fe 2 O 3 and Cr 2 O 3 indicate a localized state below 500 K. Local fields and relaxation rates are measured and interpreted. | In this paper, we investigate the performance of the Sub-carrier Multiplexed-Free Space Optics (SCM-FSO) for transmitting Code Division Multiple Access (CDMA) signals in terms of Carrier-to-Noise-plus-Interference Ratio (CNIR) and Bit Error Rate (BER), under Gamma-Gamma turbulent FSO channel. We propose an analytical model for optimization of the SCM-FSO link and a closed-form BER expression taking into account the nonlinear effects of the SCM optical link as well as the strong atmospheric turbulence of the FSO channel. We emphasize how the choice of optimal optical modulation index (OMI) can increase the received CNIR and also its dependency on the attenuation of the FSO channel. We then discuss the effect of atmospheric turbulence on the received BER. It is shown that, for a high quality CDMA signals reception over the SCM-FSO system, the link has to be engineered to perform optimally in terms of received optical power, number of carriers and OMI. | eng_Latn | 13,370 |
OTSSP167 Abrogates Mitotic Checkpoint through Inhibiting Multiple Mitotic Kinases | OTSSP167 was recently characterized as a potent inhibitor for maternal embryonic leucine zipper kinase (MELK) and is currently tested in Phase I clinical trials for solid tumors that have not responded to other treatment. Here we report that OTSSP167 abrogates the mitotic checkpoint at concentrations used to inhibit MELK. The abrogation is not recapitulated by RNAi mediated silencing of MELK in cells. Although OTSSP167 indeed inhibits MELK, it exhibits off-target activity against Aurora B kinase in vitro and in cells. Furthermore, OTSSP167 inhibits BUB1 and Haspin kinases, reducing phosphorylation at histones H2AT120 and H3T3 and causing mislocalization of Aurora B and associated chromosomal passenger complex from the centromere/kinetochore. The results suggest that OTSSP167 may have additional mechanisms of action for cancer cell killing and caution the use of OTSSP167 as a MELK specific kinase inhibitor in biochemical and cellular assays. | In this study, the authors propose an optical microwave (MW) radio-over-fibre system in which an integrated dual-parallel Mach-Zehnder modulator (DP-MZM) is biased at the maximum transmission biasing point. A single drive Mach-Zehnder modulator, in series with the DP-MZM, is used to modulate the 1 GHz radio frequency data onto the optical carrier. They characterise the efficiency of the practical system in terms of power penalty and error vector magnitude. Two modulation schemes are investigated, namely binary phase shift keying (BPSK) and quadrature phase shift keying (QPSK) over fibre spans of 10 and 25 km of standard single mode fibre. The results show that the second-order sideband of MW has the potential to provide error free transmission for BPSK and QPSK. The error free communication system is achieved for BPSK at 10 and 25 km fibre spans at optical launch power (OLP) of 7 dBm, whereas for QPSK, the OLP is ~11 and ~12 dBm for 10 and 25 km fibre spans, respectively. | eng_Latn | 13,371 |
Proposal of a Hierarchical and Distributed Method for Selecting a Radio Network and a Transmission Mode | The deployment of heterogeneous radio networks and the deployment of Unicast Internet Protocol IP/Multicast IP architectures can impact the quality of services received by the users. The authors think that they will accept these quality variations if they have the possibility to choose the radio network and the transmission mode, multicast versus unicast. But, when choosing a radio network or a transmission mode, the choices of the users can be opposed to the choices of the operators managing the networks. To overcome this drawback, the authors defined a method allowing the users, the operators managing the networks and the service providers to cooperate in the selection process. | In this paper, we consider utilizing the space-time codes in the wideband CDMA system. We assume that there are multiple resolvable paths in the frequency selective fading channel. Analytical results show that in addition to spatial diversity, another diversity gain called multipath diversity is achievable. Performance criterion for full space multipath diversity gain is analyzed. We consider both the case that the receiver has the ideal channel state information and the case that there are errors in the channel state information available to the receiver. A RAKE receiver is used in the CDMA system to gain the multipath diversity. We derive the generalized RAKE receiver structure for the space-time block coding (STBC) coded wideband CDMA systems. The simulation results demonstrate the additional gain guaranteed by the multipath diversity. | eng_Latn | 13,372 |
Development of TMP fibre and pulp quality | The development of TMP quality is considered from the perspective of the long fibre fraction. When refined as a whole pulp, this long fibre both appears to develop in its papermaking performance at a similar rate to, and to form a less well consolidated network than the shorter fibre. As this long fibre is visually dominant in the paper surface, it is important that it receive additional, separate refining to improve its relative performance. Aspects of the achievement of freeness reduction by fibre cutting are examined, together with the quality implications of this for energy reduction achieved by increased refining intensity. Improvements in long fibre behaviour, when sulfonated as in the CTMP processes, are compared to that of TMP fibre. | We propose a novel machine learning based equalization algorithm for bandwidth-limited IM-DD PON in C-band. 50Gb/s/λ. PAM4 transmission is demonstrated over 20km SSMF using a 10G-class transmitter with 21dB loss budget without amplification. | eng_Latn | 13,373 |
Novel Low Complexity Pulse-Triggered Flip-Flop for Wireless Baseband Applications | A low complexity dual-mode pulse-triggered FF design for wireless baseband processing is presented in this paper. It supports both single-edge- and double-edge-triggered operations subject to a mode select control. Due to the novelty in pulse generator design, the layout area overhead is only 8% when compared with other single-mode counterpart design. Postlayout simulations in TSMC 1P6M 0.18 μm CMOS process model also indicate that the proposed design is as efficient as its single-mode counterpart in various performance metrics. | This paper introduces the system of digital broadcasting stream,especially notes the scrambling mechanism and the detail principle.Using FPGA as the main chip,and other additional chips,a PCB board has been constructed.It has been tested that the design and the processed data are successful.So this paper has some engineering value. | eng_Latn | 13,374 |
Optimization of Agar Diffusion Bioassay for Nisin | The four major factors agar, Tween20, culture temperature and pre-diffusion, affecting the agar diffusion bioassay for nisin were studied. The results showed that when agar concentration is 0.75%, the addition of Tween20 0.5%, and the culture temperature 30℃, the accuracy and sensitivity of agar bioassay for nisin can be improved. And the pre-diffusion at 4℃ can enhance the diffusion of nisin in agar. | We consider the throughput performance of ARQ in interfering channels, where the signal of interest as well as the interferers are subject to independent distributed Nakagami-m block fading. The key contribution is the derivation of closedform expressions for the rate-maximized throughput. For this purpose, we employ the powerful parameterization approach from [1], allowing the problem to be solved exactly in a closedform. We also consider the scaled-power, and the interferencelimited, case. | eng_Latn | 13,375 |
DWDM Transmission of OTU3 (43 Gb/s) Data over 7000km of Conventional Non-Zero Dispersion Shifted Fiber | We report DWDM transmission of 50 x 43 Gb/s (ITU-T G.709 OTU3 format) NRZ-DPSK channels over 7000km of conventional NZDSF, using a mixed Raman/EDFA system with 100km/22dB spans and an advanced FEC implemented in the OTU3 frame. | This paper proposes how to choose optimal traceback depth of Viterbi decoder in OFDM systems.The decoder is largely affected by the decoder traceback depth,because the decoder complexity increases exponentially with the decoder traceback depth.There are lots of references which are analyzed theoretically the performance caused by traceback depth,but the range is so wide that it is difficult to choose precise value.According to apply convolutioanl encoding and viterbi decoding in OFDM system,we find that the optimal decoding traceback depth is 5 times of constrained length of encoder on the basis of considering a tradeoff between performance and equipment complexity,this conclusion can be applied in other communication systems. | eng_Latn | 13,376 |
The Relationship between Transmission Coefficient and Coupling Loss Factor | During the discussion there was a debate on the relationship between the transmission coefficient and the coupling loss factor. | The paper presents a method for reception, decoding and reconstruction of DVB-T signal for the purpose of using it in passive coherent location (PCL) as a reference. The signal is received using universal COTS components not dedicated for DVB-T, contrary to common television receivers. The proposed algorithm is tested on real-life signals. | eng_Latn | 13,377 |
Carrier transport in oxygen‐rich polycrystalline‐silicon films | A symmetrical‐Schottky‐barrier (SSB) band model is proposed for the carrier transport in oxygen‐rich polycrystalline‐silicon films. Semiquantitative analyses were made, comparing a one‐dimensional depletion approximation, with voltage and temperature‐dependent current measurements. The band gap is found to be similar to that of single‐crystalline Si, with electrons as the majority carriers. A net donor state density of 2.3×1019 cm−3, 0.12 eV below the conduction band edge, exists in the grains of the polycrystalline silicon, and these donors are completely ionized in the presence of large grain‐boundary surface states. This results in a grain‐boundary surface‐charge density of −2.3×1013q/cm2, setting up overlapped space‐charge regions which give rise to the SSB band structure with a maximum band bending of 0.44 eV. The Fermi level is found to be pinned at the midgap at the grain boundaries—suggesting the existence of an amorphous intergrain layer. At and above 373 K, the carrier transport is by thermionic... | Abstract Optical wireless communication technologies are finding a greater interest and wider attention within the research community of late. In this paper, we investigate the performance of a free space optical communication system over a generic propagation model called M -distributed channel in the presence of atmospheric turbulence. We analyzed a Subcarrier intensity-modulated free-space optical (SIM-FSO) communication system using DPSK and closed form expressions are derived using Meijer G function for bit error rate, channel capacity and outage probability for M -distribution. | eng_Latn | 13,378 |
A Novel Learning Vector Quantization Inference Classifier | One of the popular tools in pattern recognition is a neuro-fuzzy system. Most of the neuro-fuzzy systems are based on a multi-layer perceptrons. In this paper, we incorporate learning vector quantization in a neuro-fuzzy system. The prototype update equation is based on the learning vector quantization while the gradient descent technique is used in the weight update equation. Since weights contain informative information, they are exploited to select a good feature set. There are 8 data sets used in the experiment, i.e., Iris Plants, Wisconsin Breast Cancer (WBC), Pima Indians Diabetes, Wine, Ionosphere, Colon Tumor, Diffuse Large B-Cell Lymphoma (DLBCL), and Glioma Tumor (GLI_85). The results show that our algorithm provides good classification rates on all data sets. It is able to select a good feature set with a small number of features. We compare our results indirectly with the existing algorithms as well. The comparison result shows that our algorithm performs better than those existing ones. | The design of the LTE physical layer (PHY) is heavily influenced by the requirements for high peak transmission rate (100 Mbps DL/50 Mbps UL), spectral efficiency and multiple channel bandwidths (1.25–20 MHz). Unfortunately, the existing WCDMA turbo interleaver does not permit an efficient high throughput implementation. That is why the 3rd Generation Partnership Project (3GPP) has proposed the quadratic polynomial permutation (QPP) interleaver to rectify this situation. In this paper, we will study the performances of QPP interleaver for LTE encoder channel for different configurations of LTE system and we study the effect of LTE channel turbo encoder for the transmission over a wireless multipath channel. | eng_Latn | 13,379 |
Enhanced out-coupling factor of microcavity organic light-emitting devices with irregular microlens array | We studied microcavity organic light-emitting devices with a microlens system. A microcavity for organic light-emitting devices (OLED) was fabricated by stacks of SiO2 and SiNx layers and a metal cathode together with the microlens array. Electroluminescence of the devices showed that color variation under the viewing angle due to the microcavity is suppressed remarkably by microlens arrays, which makes the use of devices acceptable in many applications. It was also demonstrated that the external out-coupling factor of the devise increases by a factor of ~1.8 with wide viewing angles compared to conventional OLEDs. | In this paper, we propose decision feedback equalizer based on LDPC (Low Density Parity Check) code for fast processing and performance improvement. LDPC code has good error correcting ability and performance approaching Shannon capacity. However, it has more long parity check matrix and the number of iteration. In proposed system, MSE (mean square error) of signal between decision device and decoder is fed back to equalizer. If we use this method, proposed system can improve performance because it corrects estimated channel response more accurately. In addition, proposed system can reduce complexity because it has a lower number of iterations than system that does not include feedback at same performance. We evaluate performance of OFDM system considered CFO and phase noise in multipath channel via simulation. | eng_Latn | 13,380 |
A 900MHz high efficiency and linearity adaptive CMOS power amplifier | A high efficiency, linear, adaptive radio frequency (RF) power amplifier (PA) is presented. The working frequency is about 900MHz. The circuit employs a self-bias cascode for a higher performance and an adaptive bias to enhance linear and efficiency of the PA as well. This power amplifier is designed with the SMIC 0.18um CMOS RF process. The power supply is 1.8V. The simulation results show that the PA has a power gain of 30dB. In addition, the Power-Added Efficiency is over 33%. | This paper addresses the problem of channel and propagation delay estimation in asynchronous DS/CDMA systems. We consider the uplink connection in DS/CDMA with long spreading codes. The MIMO stochastic gradient algorithm proposed in [6] is estimating a linear combination of the channel impulse responses and the propagation delays. This estimate suffices for the equalization purposes. The propagation delays are estimated with a simple matching scheme. | eng_Latn | 13,381 |
Non-Orthogonal Coded Access for Contention-Based Transmission in 5G | The fifth generation (5G) wireless network faces unprecedented massive concurrent random access requests in uplink (UL) contention-based (CB) transmission. In this paper, a non-orthogonal coded access (NOCA) UL transmission in combination with parallel interference cancellation (PIC) based reception scheme at base station is investigated. Non-orthonormal code generated by Zadoff-Chu (ZC) sequences is used to spread the data bits over orthogonal frequency division multiple (OFDM) symbols. It is shown through both link level and system level simulations that in dense urban scenario NOCA-PIC scheme is capable of working in highly overloaded system conditions. It can support more than 4 times concurrent random access number compared with OFDM based CB transmission. | Purpose ::: Surveillance after orchiectomy alone has become popular in the management of clinical stage I nonseminomatous germ cell testicular tumors (CSI NSGCTT), and adjuvant chemotherapy has been accepted in high-risk CSI NSGCTT. Because of the late toxicity of standard radiotherapy in CSI testicular seminoma (SGCTT), this therapeutic approach has been accepted also in the management of CSI SGCTT. In the current study, we analyzed single-center experience with risk-adapted therapeutic approaches (active surveillance and adjuvant chemotherapy) in patients with CSI SGCTT. | eng_Latn | 13,382 |
Over 200 mW Operation of Single-Lateral-Mode 785 nm Laser Diodes with Window-Mirror Structure | The high power operation of the lateral mode stabilized 785nm AlGaAs LD with the window-mirror structure has been demonstrated. The stable lateral mode operation up to 250mW (kink level of 280 mW) is realized. To the best our knowledge, this is the highest power record among the narrow stripe LDs with a wavelength of 785 nm and is suitable for CD ROM disc drives. | This paper introduces the optimal widely linear (WL) minimum variance distorsionless response (MVDR) beamformer for the reception of an unknown signal of interest (SOI) corrupted by potentially second order (SO) noncircular background noise and interference. The SOI, whose waveform is unknown, is assumed to be SO noncircular with arbitrary noncircular properties. In the steady state and for SO noncircular SOI and/or interference, this new WL beamformer, that is derived from an original orthogonal decomposition, is shown to always improve the performance of both the well-known Capon's beamformer and a WL MVDR beamformer introduced recently in the literature. This optimal WL MVDR beamformer is first introduced and some of its performance are analyzed. Then, several adaptive implementations of this optimal WL beamformer are presented. | yue_Hant | 13,383 |
PE modelling of radiowave propagation over the sea | In order to assist the engineer designing a radar or trying to assess its performance in a marine environment, extremely difficult problem which must be solved is the assessment of the effect of a given meteorological environment, including the sea state, on electromagnetic propagation. The author presents applications of the parabolic equation method to the propagation modelling. | In this paper a programmable and area-efficient decoder architecture supporting two decoding algorithms for Block-LDPC codes is presented. The novel decoder can be configured to decode in either TPMP or TDMP decoding mode according to different Block-LDPC codes, essentially combining the advantages of two decoding algorithms. With a regular and scalable data-path, a Reconfigurable Serial Processing Engine (RSPE) is proposed to achieve area efficiency. To verify our proposed architecture, a flexible LDPC decoder fully compliant to IEEE 802.16e applications is implemented on a 130nm 1P8M CMOS technology with a total area of 6.3mm2 and maximum operating frequency of 250MHz. The chip dissipates 592mW when operates at 250MHz frequency and 1.2V supply. | eng_Latn | 13,384 |
A network for combining radio systems at 4, 6 and 11 kmc | Development of the broadband horn reflector antenna has permitted the simultaneous radiation and reception of radio signals on different frequencies in the three common-carrier bands in which the Bell System has developed radio relay systems. A necessary adjunct to the antenna is a network to combine or separate the common carrier bands and also to combine or separate the two polarizations of any one band. The particular form of the network that is described was designed to meet strict system requirements on impedance match, insertion loss and cross-coupling between ports. | The paper provides WiMAX BS (base station) MAC design, implementation discussion with performance analysis based on Intel IXP2350, which include MAC design key issues discussion, base station usage model and architecture, MAC hardware and software high level design and relevant performance analysis. Especially, the WiMAX base station is user-specific, and WiMAX MAC software is one of the most important base station components, so we discuss in details about MAC data plane software design and performance pre-analysis based on IXP2350 micro engines. Current hardware GE forwarding test and data plane software pre-analysis shows that the design scheme can meet WiMAX base station system performance requirement. | eng_Latn | 13,385 |
Method for Accessing randomly in Time Division Duplex Mode | PURPOSE: A random access method in a TDD(Time Division Duplex) mode is provided to reduce collisions between users during transmission of UpPTS(Uplink Pilot Time Slot) in the TDD mode having a low speed chip rate, so as to perform a random access by distinguishing a service having a high priority from a service having a low priority. CONSTITUTION: A user having data to be transmitted selects a service identifier in accordance with priority of the data. A mobile communication system selects one of sub frames in accordance with the selected service identifier, and selects one of code sequences assigned in the sub frames, then transmits a specific code sequence to a base station through a UpPTS of the selected sub frame. The mobile communication system transmits the data to the base station through a predetermined channel, by using a time slot and a channelization code mapped in the specific code sequence and the selected sub frame according to a response signal of the base station for the transmitted UpPTS. | This paper describes the theoretical basis for a design methodology which enables control of the fundamental tradeoff between speed, dynamic range, and power consumption in switched current cells. The presented methods are applied to the design of a very high dynamic range current memory cell and simulation results are given. > | yue_Hant | 13,386 |
A DCA-Based Approach for Outage Constrained Robust Secure Power-Splitting SWIPT MISO System | This paper studies the worst-case secrecy rate maximization problem under the total transmit power, the energy harvesting and the outage probability requirements. The problem is nonconvex, thus, hard to solve. Exploiting the special structure of the problem, we first reformulate as a DC (Difference of Convex functions) program. Then, we develop an efficient approach based on DCA (DC Algorithm) and alternating method for solving the problem. The computational results confirm the efficiency of the proposed approach. | In this paper, we consider utilizing the space-time codes in the wideband CDMA system. We assume that there are multiple resolvable paths in the frequency selective fading channel. Analytical results show that in addition to spatial diversity, another diversity gain called multipath diversity is achievable. Performance criterion for full space multipath diversity gain is analyzed. We consider both the case that the receiver has the ideal channel state information and the case that there are errors in the channel state information available to the receiver. A RAKE receiver is used in the CDMA system to gain the multipath diversity. We derive the generalized RAKE receiver structure for the space-time block coding (STBC) coded wideband CDMA systems. The simulation results demonstrate the additional gain guaranteed by the multipath diversity. | kor_Hang | 13,387 |
Comparative study on optical fiber communication multiplexing technology | The optical multiplexing technology is a feasible method for improving the capacity of optical fiber communication network by exploiting multiple wavelengths on each fiber used for data transmission independently. With the help of this technology, optical fiber communication network capacity can be greatly improved to meet the increasing requirements of the network | Originally published Microwave Opt Technol Lett 53: 751–757, 2011. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53: 1685, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26162 ::: ::: ::: ::: (Original article DOI 10.1002/mop.25828) | eng_Latn | 13,388 |
Mobile Throughput of 802.11b from Moving Vehicle to Roadside Access Point | This paper documents some tests of 802.11b wireless communication technology for vehicle to roadside communication. Data has been collected for a single vehicle communicating with a dedicated roadside antenna. The work is part of a larger effort to benchmark possible throughput of off-the-shelf wireless technologies. The results show that high-speed communication is possible over distances of up to 1 kilometer. | This paper discusses the inherent mechanism of adding windows technology and its application in NC-OFDM systems,for two windows and different roll-off factors,the simulation is conducted to compare the performance of the power spectrum out-of-band attenuation of the NC-OFDM signals.The results indicate that the attenuation is improved due to the added windows;meanwhile,the signals out-of-band attenuation is also different because of various windows and roll-off factors. | eng_Latn | 13,389 |
Demodulation of space frequency coded transmit diversity based on China's digital terrestrial television broadcasting | The receiver performance degradation is a serious problem in time-variant,deep fading channels with high power echoes and long channel delay.A demodulation method for space frequency coded transmit diversity was developed based on the digital television terrestrial multimedia broadcasting(DTMB) system to solve the problem.The traditional space frequency decoder uses the orthogonal inverse matrix with the assumption that the adjacent sub-channel responses in the frequency domain are similar,which is no longer valid in deep fading channels.The proposed space frequency decoding method works without the assumption mentioned above.Both theoretical analysis and computer simulation show that the method can effectively improve the receiver performance in fading channels with strong frequency selectivity. | Publisher’s Note: This paper, originally published on 12 July 2016, was replaced with a corrected/revised version on 26 July 2016. If you downloaded the original PDF but are unable to access the revision, please contact SPIE Digital Library Customer Service for assistance. ::: ::: We have developed a terahertz time domain spectroscopy system (THz TDS). For THz generation, optical rectification process and for detection, electro-optic sampling processes are used. Identical cut ZnTe crystals are used for both generation and detection of THz radiation.This spectroscopy system can be used for the noninvasive and contactless electrical and optical characterizations of various samples. In this work spectroscopic measurements of pure, Chromium and Indium doped GaSe crystals within 0.4 THz to 3 THz range are taken by the developed set-up to study the dielectric response of the samples. | eng_Latn | 13,390 |
The workflow management based on PDM | Based on a brief account of the PDM,expounded the concept of Workflow Management System in emphases,bring into effect and purpose.According to the Management object of Corporation.And then discussed upon the three function of system even more.Workflow Management is the most important function in PDM process.Developed and application of the system Provided strong foundation on implementing PDM in the company. | We have devised a new system for forming the antenna beam in a com- bined OFDM and MIMO scheme. In this scheme, the OFDM signal is divided among multiple bands, and the divided signals are transmit- ted on an appropriate beam of each sub-band. In this paper, We have described the system configuration of the proposed multi-band OFDM- MIMO scheme for use over multipath wireless channels. And, we have discussed the performance of adaptive modulation and error correction of the system. | eng_Latn | 13,391 |
Pulse Shaping Filter and PAPR for GFDM System | In traditional CP-OFDM technology exist has two drawbacks,i.e.,the adding of cyclic prefix would result in low spectrum efficiency and it is sensitive to the Doppler frequency shift.This paper principally discusses the issue of pulse shaping filter for GFDM(generalized frequency division multiplex) system.With the suitable arrangement,GFDM system could match the channel propagation against the inter-symbol interference and inter-carrier interference.Finally,PAPR(peak-to-average-power-ratio) for GFDM system is exoounded,and the bit error ratio performance in presence of HPA(high-power amplifier) also analyzed. | The flow pulsation in a plane-parallel gear pump with 3-idlers was analyzed,formulae for calculating displacement,average flow velocity,instantaneous flow and pulsation flow were derived.It was pointed out that this sort of gear pump can provide higher flow pulsation frequency when taking teeth number Z=3K±1. | eng_Latn | 13,392 |
Analysis of DC System Grounding Fault and Its Improved Measures in Power Plant | DC system network is widely distributed in power plant, and because some of the work environment is poor, DC system occurs to the phenomenon of insulation reduction easily. The insulation of DC system directly affects the stability and reliability of DC control and signal monitoring circuit, so it is very important to detect and deal with the one point grounding fault when it happens in DC system. In this paper, it introduced DC system grounding fault in power plant, and analyzed abnormal phenomenon in DC system in detail, and gave improved measures according to the analysis conclusion. | In this paper, a digital down converter (DDC) applied on wide bandwidth digital IF receiver is design and implemented by FPGA. This DDC can translate digital IF signal to baseband, extract desired channel, decimate the sample sequence, multirate converter and channel shape. Using Top-Down design method, the whole DDC function is divided to many units implemented respectively and organized to the module library. When applying DDC on receiver, these function modules are selected, configured and optimized to a complex module a designed to satisfy the wireless system demand. This DDC based module library and re-configurable structure are more flexible and programmable than classic ASIC down converter. | eng_Latn | 13,393 |
Phase detection involving parity-check equations and suited to transmissions at low signal to noise ratio | We introduce in this paper a carrier phase detector suited to transmissions at very low signal to noise ratio. Based on the soft decoding of parity check equations, the synchronization scheme proposed here for a QPSK modulation outperforms a classical decision directed algorithm over a Gaussian channel, and is notably well adapted to satellite applications. | Problems associated with the modelling and calculation of quasi-steady-state postfault regimes are considered for abrupt power unbalances. A program permitting calculation of quasi-steady-state postfault regimes with allowance for frequency dynamics and the investigation of their stability is described. Results of calculations based on this program are compared with experiments using an electrodynamic model. It is shown that allowance must be made for frequency dynamics in the analysis of postfault regimes. 9 refs. | eng_Latn | 13,394 |
A study on adaptive real time video over LTE | LTE, The next generation mobile network system by 3GPP, only allows IP-based transport. Traditional telephony services such as voice and video real-time communication will be provided through the ... | Abstract We report ESR experiments on a LaAl 2 sample doped with 6% Gd. The experiments were performed at 1, 3, 9 and 35 GHz. We find for T ≈ T c essentially a frequency independent shift of H res , but a frequency dependence for the minimum in the linewidth. The results will be discussed in terms of static internal fields and dynamic field fluctuations. | eng_Latn | 13,395 |
Capacity ofMIMO Propagation Indoor Channel Comparison of Indoor to Indoor and Outdoor to Indoor Radio Link Performances | This paper presents an experimental study of the propagation channel in Indoor environment with two radio link configurations: outdoor to indoor (O2I) and indoor to indoor (I2I). The experimentation has been carried out with a MIMO set-up which allows a full 3D space-time characterization of the channel. The analysis of the measurement is based on the Power Delay Profile (PDP) and on the Directions of Arrival (DoA) and Departure (DoD) of the waves. Evaluations of MIMO capacity are realized considering degrees of freedom of the channel, angular spread in azimuth and in elevation. The results shows the impact of transmitter locations and of the frequency on the space-time characteristics of the channel and consequently on the MIMO system performances. | In this paper the determination of transfer functions from inside an Airbus A319 to outside the aircraft in a frequency range from 2 GHz to 8 GHz is presented. Two different aspects have been investigated. The first is the determination of the fuselage attenuation of the aircraft in order to see, if existing airport communications and radar systems could be disturbed by onboard installed equipment. The second concerns possible coupling from inside the aircraft to different relevant aircraft navigation and communication antennas which are mounted outside the aircraft along the fuselage. The different results of these two measurements are presented and possible interferences with existing systems are discussed. | eng_Latn | 13,396 |
FPGA prototyping of single-polarization 112-Gbit/s optical transceiver for optical multilevel signaling with delay detection | We develop full-rate / fully-functional FPGA-based high-speed optical 16-APSK/QAM transceiver prototype using optical delay-detection for single-polarization 100-Gbit/s/channel short- to mid-range fiber transmission. Four channel WDM (448-Gbit/s) field trial over 18.2-km SMF is also performed. | A novel phasor computation algorithm is presented in this paper. The real and imaginary part filters of this algorithm have identical magnitude frequency characteristic (IMFC) at all the frequencies and orthogonal phase frequency characteristic (PFC) at fundamental frequency. Considering the conditions of the same magnitude frequency characteristic (MFC) and the orthogonal PFC, the two-sample algorithm is derived. Once two-sample orthogonal filters with IMFC are obtained, the algorithm design is just to select proper shapes and lengths of windows, which determine the filtering performance and response-time, respectively. This method could be applied to design filter in any window-length, especially in short-window. Therefore, this class of phasor algorithms is suitable for EHV transmission line protection where a short-window is crucial for fast response and better operation performance. The proposed algorithm has been applied to a series of EHV relay devices by China Xuchang Relay Group. | eng_Latn | 13,397 |
Design of Antenna Array and Hybrid Receiver in Sidehaul System | Recently, 3rd Generation Partnership Project (3GPP) has developed sidehaul system to cope with the explosively increasing mobile data traffic. The sidehaul system is based on single carrier-frequency division multiple access (SC-FMDA) due to its low peak to average power ratio (PAPR). Also, antenna array is designed to support multiple input multiple output (MIMO) in a restricted space. In this paper, we design the antenna array about uniform linear array (ULA), uniform circular array (UCA) and uniform planar array (UPA), and analysis the performance in sidehaul system. In addition, we propose the novel hybrid receiver full suppression cancellation (FSC) to reduce the interference from neighbor cell in sidehaul system. The proposed receiver can suppress and cancel the interference by combining interference rejection combining (IRC) with successive interference cancellation (SIC). | timedomainresource allocation withdifferent power allocation methods, e.g., water-filling andequal power Inthis paper, wepresent theadaptive multiuser frequency-allocation. Through simulations we showthat1)system timedomainradioresource allocation modelwhich capacity withthefrequency-time domainresource adaptively allocates theradioresource jointly inthe allocation ismuchmorethanthatwithonlyfrequency frequency andtimedomaintoexploit thefrequencydomain resource allocation; 2)fortheproposed allocation diversity andtimediversity aswellasmultiuser diversity. method theperformance ofwater-filling powerallocation is Thenwegive anin-depth capacity analysis oftheproposed almost thesameasthatoftheequal powerallocation, radioresource allocation withfrequency-time domain especially whenthenumber ofuserislarge. poweradaptation inthedownlink OFDMA systems and drawacomparison with theconventional frequency domain 2.FREQUENCY-TIMEDOMAIN RESOURCE resource allocation method. Simulation results showthat 1) ALLOCATIONMODELS | eng_Latn | 13,398 |
Design, simulation and implementation of a self-oscillating control circuit to drive series resonant inverter feeding a brazing induction furnace | This research deals with the design and simulation of induction furnace power source (inverter) using MATLAB package. This source designed to lock on the resonant frequency of the load by using self-oscillating technique, also it has the capability to control the power supplied to the load using phase shift pulse width modulation (PSPWM) technique. These characteristics used to overcome the load nonlinear behavior during the brazing process and to achieve soft switching of the inverter elements. Also, the inverter has the capability to operate with or without load (workpiece). The implemented prototype operates at a frequency range (50–100)kHz and 10kW was successfully used for brazing two copper workpieces. | In this paper, we investigate the performance of the Sub-carrier Multiplexed-Free Space Optics (SCM-FSO) for transmitting Code Division Multiple Access (CDMA) signals in terms of Carrier-to-Noise-plus-Interference Ratio (CNIR) and Bit Error Rate (BER), under Gamma-Gamma turbulent FSO channel. We propose an analytical model for optimization of the SCM-FSO link and a closed-form BER expression taking into account the nonlinear effects of the SCM optical link as well as the strong atmospheric turbulence of the FSO channel. We emphasize how the choice of optimal optical modulation index (OMI) can increase the received CNIR and also its dependency on the attenuation of the FSO channel. We then discuss the effect of atmospheric turbulence on the received BER. It is shown that, for a high quality CDMA signals reception over the SCM-FSO system, the link has to be engineered to perform optimally in terms of received optical power, number of carriers and OMI. | eng_Latn | 13,399 |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.