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Performance analysis of space-time transmit diversity techniques for multi-antenna WCDMA systems
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作者 杨馨 方昕 尤肖虎 《Journal of Southeast University(English Edition)》 EI CAS 2004年第3期261-266,共6页
Several space-time coding based transmit diversity techniques for wideband code division multiple access (WCDMA) systems with four transmitter antennas are investigated. Performances of the rake receivers are analyzed... Several space-time coding based transmit diversity techniques for wideband code division multiple access (WCDMA) systems with four transmitter antennas are investigated. Performances of the rake receivers are analyzed and compared with those of the multi-antenna receive diversity techniques. Theoretical analysis shows that the multi-antenna transmit diversity techniques provide considerable performance gain at the mobile receiver in the wireless channel with less inherent multipath diversity, especially the G4 coding based scheme. Compared with the multi-antenna receive diversity techniques with the same diversity order, the transmit diversity techniques introduce much more multi-access plus multipath interference and require measures of interference suppression in the multi-user environments. 展开更多
关键词 Code division multiple access Diversity reception Multipath propagation Radio transmission Receiving antennas
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A rigorous proof of MIMO channel capacity's increase with antenna number
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作者 GONG Jian-min M. R. Soleymani J. F. Hayes 《Optoelectronics Letters》 EI 2008年第4期280-282,共3页
It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output(MIMO) communication systems.In this letter,a simple proof is pre... It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output(MIMO) communication systems.In this letter,a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas.The proof is based on the famous capacity formula of Foschini and Gans with matrix theory. 展开更多
关键词 antennaS Communication systems Matrix algebra MIM devices MULTIPLEXING Receiving antennas
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Adaptive Energy Efficient Power Allocation Scheme for DAS with Multiple Receive Antennas
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作者 Wang Ying Yu Xiangbin +3 位作者 Wang Hao Chu Junya Dong Tao Qiu Sainan 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第4期656-663,共8页
Energy efficiency(EE)of downlink distributed antenna system(DAS)with multiple receive antennas is investigated over composite Rayleigh fading channel that takes the path loss and lognormal shadow fading into account.O... Energy efficiency(EE)of downlink distributed antenna system(DAS)with multiple receive antennas is investigated over composite Rayleigh fading channel that takes the path loss and lognormal shadow fading into account.Our aim is to maximize EE which is defined as the ratio of the transmission rate to the total consumed power under the constraints of the maximum transmit power of each remote antenna.According to the definition of EE,the optimized objective function is formulated with the help of Lagrangian method.By using the Karush-KuhnTucker(KKT)conditions and numerical calculation,considering both the static and dynamic circuit power consumptions,an adaptive energy efficient power allocation(PA)scheme is derived.This scheme is different from the conventional iterative PA schemes based on EE maximization since it can provide closed-form expression of PA coefficients.Moreover,it can obtain the EE performance close to the conventional iterative scheme and exhaustive search method while reducing the computation complexity greatly.Simulation results verify the effectiveness of the proposed scheme. 展开更多
关键词 distributed antenna system(DAS) energy efficiency(EE) power allocation(PA) composite fading multiple receive antennas
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PERFORMANCE ANALYSIS OF TAS/MRC-BASED SCHEME IN TIME-VARYING RAYLEIGH FADING CHANNELS
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作者 Chen Mingxue Xu Chengqi 《Journal of Electronics(China)》 2010年第2期151-156,共6页
This paper investigates a Multiple-Input Multiple-Output (MIMO) scheme combining Transmit Antenna Selection and receive Maximal-Ratio Combining (TAS/MRC) in time-varying Rayleigh fading channels. We first present new ... This paper investigates a Multiple-Input Multiple-Output (MIMO) scheme combining Transmit Antenna Selection and receive Maximal-Ratio Combining (TAS/MRC) in time-varying Rayleigh fading channels. We first present new closed-form expressions for optimal received Signal-to-Noise Ratio (SNR),which is expressed in polynomial form. These are used to analyze ergodic capacity,outage probability and Bit Error Rate (BER) of TAS/MRC systems. Numerical results are presented to validate the theoretical analysis. 展开更多
关键词 Multiple-Input Multiple-Output (MIMO) Transmit antenna Selection and receive Maximal-Ratio Combining (TAS/MRC) Ergodic capacity Outage probability
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Simplified 3D Fading Channels Adopted in MIMO Beamforming Schemes
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作者 Joy Iong-Zong Chen Bo Huei Lee 《Journal of Electronic Science and Technology》 CAS CSCD 2015年第2期139-143,共5页
A simplified three-dimension(3D) fading channel model deployed in a multi-input multi-output(MIMO) beamforming system is explored in this article.Both angle of arrival(AoA) and angle of departure(Ao D) which i... A simplified three-dimension(3D) fading channel model deployed in a multi-input multi-output(MIMO) beamforming system is explored in this article.Both angle of arrival(AoA) and angle of departure(Ao D) which impact the overall system performance are examined. The numerical results are given for validating the accuracy of the theoretical derived formulas. Furthermore, the performances of the model with different number of transmitters and receivers are studied and compared. The increment in Ao A parameters definitely generates the impact of the system performance when the consideration of simplified 3D channels. 展开更多
关键词 simplified fading arrival spatially receiver definitely mutual transmit departure antenna
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Compound parabolic concentrator applied as receiving antenna in scattering optical communication 被引量:1
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作者 方靖岳 张海良 +3 位作者 贾红辉 尹红伟 常胜利 秦石乔 《Chinese Optics Letters》 SCIE EI CAS CSCD 2010年第5期478-481,共4页
The two-dimensional(2D) compound parabolic concentrator's(CPC) characteristics are analyzed.It is shown that CPC's height is taller and its light collecting ability is stronger with the CPC's field of view decr... The two-dimensional(2D) compound parabolic concentrator's(CPC) characteristics are analyzed.It is shown that CPC's height is taller and its light collecting ability is stronger with the CPC's field of view decreasing when the bottom radius is unchanged.According to the ZEMAX analysis,CPC is good at collecting optical signal,and the antenna combining CPC with hemispherical lens can gather more optical signal than a single CPC or CPCs combined in series.The light propagation of scattering optical communication based on multiple scattering is simulated by Monte Carlo method,and the results show that using CPC as receiving antenna can strengthen communication system's signal collecting ability and increase its communication distance. 展开更多
关键词 Communication systems Concentration (process) Lens antennas Light propagation Monte Carlo methods Optical signal processing Parabolic antennas Receiving antennas SCATTERING
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Performance of Adaptive Subchannel Assignment-Based MIMO/OFDM Systems over Multipath Fading Channels
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作者 潘亚汉 Khaled Ben Letaief 曹志刚 《Tsinghua Science and Technology》 SCIE EI CAS 2006年第1期19-24,共6页
Adaptive antenna arrays at both the base and mobile stations can further increase system capacity and improve the quality of service of conventional orthogonal frequency division multiplexing (OFDM) systems. Convent... Adaptive antenna arrays at both the base and mobile stations can further increase system capacity and improve the quality of service of conventional orthogonal frequency division multiplexing (OFDM) systems. Conventional adaptive antenna array-based multiple-input multiple-output (MIMO)/OFDM systems use the sub-carriers characterized by the largest eigenvalue to transmit the OFDM symbols. This paper describes the performance of adaptive subchannel assignment-based MIMO/OFDM systems over multipath fading channels, The system adaptively selects the eigenvectors associated with the relatively large subchannel eigenvalues to generate the antenna array weights at the base and mobile stations and then adaptively assigns the corresponding best subchannels to transmit the OFDM symbols. Simulation results show that the proposed system can achieve better performance than the conventional adaptive antenna arraybased MIMO/OFDM system over multipath fading channels. 展开更多
关键词 multiple-input multiple-output (MIMO)/orthogonal frequency division multiplexing (OFDM) adaptive subchannel assignment joint transmit and receive antenna array weighting multipath fading channel
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