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Low-complexity and fast convergent multiuser detections for impulse UWB systems
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作者 郑霖 Qiu Hongbing 《High Technology Letters》 EI CAS 2008年第2期141-146,共6页
To solve the problem that the conventional detections in DS-CDMA suffer from high complexity and poor robustness for the time-hopping pulse signals, the received pulse signals were remodeled, and a mulfipath-free dete... To solve the problem that the conventional detections in DS-CDMA suffer from high complexity and poor robustness for the time-hopping pulse signals, the received pulse signals were remodeled, and a mulfipath-free detection scheme, which provides a simple approach to select samples of received signals, was introduced. By this scheme, the subsequent multiuser detection (MUD) would get rid of the mis- match due to the correlative multipath signal in IR-UWB. In addition, a computationally efficient recur-sive least squares (RLS) type algorithm based on least mean fourth (LMF) criterion is derived to suppress multi-access interference. The proposed multiuser detection algorithm performs well at low complexity, even in dense muhipath environment. 展开更多
关键词 ULTRA-WIDEBAND multiuser detection (MUD) multipath interference (MPI) leastmean fourth (LMF)
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Cluster-Based Massive Access for Massive MIMO Systems
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作者 Shiyu Liang Wei Chen +2 位作者 Zhongwen Sun Ao Chen Bo Ai 《China Communications》 SCIE CSCD 2024年第1期24-33,共10页
Massive machine type communication aims to support the connection of massive devices,which is still an important scenario in 6G.In this paper,a novel cluster-based massive access method is proposed for massive multipl... Massive machine type communication aims to support the connection of massive devices,which is still an important scenario in 6G.In this paper,a novel cluster-based massive access method is proposed for massive multiple input multiple output systems.By exploiting the angular domain characteristics,devices are separated into multiple clusters with a learned cluster-specific dictionary,which enhances the identification of active devices.For detected active devices whose data recovery fails,power domain nonorthogonal multiple access with successive interference cancellation is employed to recover their data via re-transmission.Simulation results show that the proposed scheme and algorithm achieve improved performance on active user detection and data recovery. 展开更多
关键词 compressive sensing dictionary learning multiuser detection random access
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Comparison of Two Neural Networks in MC-CDMA Multiuser Detection
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作者 王勇 尤肖虎 +1 位作者 陈明 卜志勇 《Journal of Southeast University(English Edition)》 EI CAS 1999年第1期17-21,共5页
MC CDMA is a thriving topic in recent years. Multiuser interference is also very severe as in DS CDMA. ML method is the best multiuser detection, but it has a computational complexity exponentially increased with th... MC CDMA is a thriving topic in recent years. Multiuser interference is also very severe as in DS CDMA. ML method is the best multiuser detection, but it has a computational complexity exponentially increased with the number of users. Mean field annealing and chaotic neural network are two promising optimum techniques. This paper applies them into the ML detection, comparison of the two methods is made. 展开更多
关键词 multiuser detection MC CDMA ML chaotic neural network MFA
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BLIND ADAPTIVE MULTIUSER DETECTOR FOR NONLINEARLY MODULATED SATELLITE MOBILE CDMA SYSTEMS 被引量:2
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作者 Shao Shixiang Yang Longxiang Kyungsup Kwak 《Journal of Electronics(China)》 2006年第3期338-340,共3页
This paper presents a novel blind adaptive noncoherent decorrelative multiuser detector for nonlinearly modulated satellite mobile Code Division Multiple Access (CDMA) systems. By using the known signature waveforms o... This paper presents a novel blind adaptive noncoherent decorrelative multiuser detector for nonlinearly modulated satellite mobile Code Division Multiple Access (CDMA) systems. By using the known signature waveforms of the counterpart earth station in the blind adaptive multiuser detector, the system performance has been improved obviously. The computation results about the convergence properties of the new detector and the previous detectors demonstrate that the proposed multiuser detector has better performance than previous multiuser detectors for nonlinearly modulated CDMA systems. 展开更多
关键词 Mobile satellite communication Nonlinear Code Division Multiple Access (CDMA) system Noncoherent detection multiuser detection
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Efficient multiuser detector based on box-constrained dichotomous coordinate descent and regularization 被引量:1
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作者 全智 刘杰 《Journal of Central South University》 SCIE EI CAS 2012年第6期1570-1576,共7页
The presented iterative multiuser detection technique was based on joint deregularized and box-constrained solution to quadratic optimization with iterations similar to that used in the nonstationary Tikhonov iterated... The presented iterative multiuser detection technique was based on joint deregularized and box-constrained solution to quadratic optimization with iterations similar to that used in the nonstationary Tikhonov iterated algorithm.The deregularization maximized the energy of the solution,which was opposite to the Tikhonov regularization where the energy was minimized.However,combined with box-constraints,the deregularization forced the solution to be close to the binary set.It further exploited the box-constrained dichotomous coordinate descent algorithm and adapted it to the nonstationary iterative Tikhonov regularization to present an efficient detector.As a result,the worst-case and average complexity are reduced down as K2.8 and K2.5 floating point operation per second,respectively.The development improves the "efficient frontier" in multiuser detection,which is illustrated by simulation results.In addition,most operations in the detector are additions and bit-shifts.This makes the proposed technique attractive for fixed-point hardware implementation. 展开更多
关键词 dichotomous coordinate descent de-regularization low complexity multiuser detection Tikhonov regularization
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NOVEL ADAPTIVE MULTIUSER DETECTIONALGORITHM BASED ON WAVELET TRANSFORM 被引量:1
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作者 ZHANGXiao-fei XUDa-zhuan YANGBei 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第2期141-146,共6页
The wavelet transform-based adaptive multiuser detection algorithm is presented. The novel adaptive multiuser detection algorithm uses the wavelet transform for the preprocessing, and wavelet-transformed signal uses L... The wavelet transform-based adaptive multiuser detection algorithm is presented. The novel adaptive multiuser detection algorithm uses the wavelet transform for the preprocessing, and wavelet-transformed signal uses LMS algorithm to implement the adaptive multiuser detection. The algorithm makes use of wavelet transform to divide the wavelet space, which shows that the wavelet transform has a better decorrelation ability and leads to better convergence. White noise can be wiped off under the wavelet transform according to different characteristics of signal and white noise under the wavelet transform. Theoretical analyses and simulations demonstrate that the algorithm converges faster than the conventional adaptive multiuser detection algorithm, and has the better performance. Simulation results reveal that the algorithm convergence relates to the wavelet base, and show that the algorithm convergence gets better with the increasing of regularity for the same series of the wavelet base. Finally the algorithm shows that it can be easily implemented. 展开更多
关键词 multiuser detection wavelet transform multi-resolution analyses multi-access interference (MAI) adaptive multiuser detection
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Low Complexity Multiuser Detection with Recursively Successive Zero-Forcing and SIC Based on Nullspace for Multiuser MIMO-OFDM System 被引量:3
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作者 Zhang Chengwen Wang Bin +1 位作者 Li Danli Tan Xuezhi 《China Communications》 SCIE CSCD 2015年第9期53-63,共11页
To improve the spectrum efficiency, this paper considers the multiuser detection with the MU-MIMO technology for multiuser MIMO-OFDM system uplink with the same subcarrier shared by multiple users. A low complexity mu... To improve the spectrum efficiency, this paper considers the multiuser detection with the MU-MIMO technology for multiuser MIMO-OFDM system uplink with the same subcarrier shared by multiple users. A low complexity multiuser detection algorithm with recursively successive zero-forcing and successive interference cancellation(RSZF-SIC) based on nullspace is proposed. The RSZF process based on the block diagonalization(BD) technique eliminates the co-channel interference(CCI) by a recursive method based on the nullspace orthogonal theorem. The SIC process detects the user signals respectively with the reasonable user detection sequence based on the results of the RSZF process. The computational complexity of the proposed algorithm is effectively reduced by reducing the total number of singular value decomposition(SVD) operations and the dimension of the SVD matrix in the recursive procedure. The performance of the proposed algorithm is improved in terms of bit error rate and sum capacity of the system, especially in the highSNR regime. 展开更多
关键词 MIMO-OFDM MU-MIMO multiuser detection co-channel interference cancellation block diagonalization successive interference cancellation
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ANALYSIS OF GROUP MULTIUSER DETECTION BASED ON COALITION GAME THEORY 被引量:1
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作者 Li Cuilian Yang Zhen 《Journal of Electronics(China)》 2009年第6期804-811,共8页
Coalition game theory is introduced to investigate the performance,fairness and stability of decorrelating group multiuser detection receiver,not only from the perspective of individual nodes,but also various coalitio... Coalition game theory is introduced to investigate the performance,fairness and stability of decorrelating group multiuser detection receiver,not only from the perspective of individual nodes,but also various coalitions and the whole system as well. Firstly,to derive how the system scale with coalition size,a stochastic model with transferable payoffs (stochastic TU-model) is provided. Secondly,to find the most preferred coalition structures from the view point of individual nodes,a model with Non-Transferable payoffs (NTU-model) is presented. Theoretical analysis and simulation results suggest that stochasticaly the grand coalition is payoff maximizing for the system as a whole,while individual nodes with good-conditioned channels may prefer local "win-win coalitions". 展开更多
关键词 Coalition game CORE multiuser detection RATIONALITY
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A novel constant modulus array for multiuser detection
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作者 张继东 郑宝玉 傅洪亮 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第1期38-42,共5页
This paper proposes a new multitarget constant modulus array structure for code division multiple access (CDMA) systems. The new algorithm for the structure is called pre-despreading and wavelet denoising constant mod... This paper proposes a new multitarget constant modulus array structure for code division multiple access (CDMA) systems. The new algorithm for the structure is called pre-despreading and wavelet denoising constant modulus algorithm (D-WD-CMA). In the new algorithm, the pre-despreading is applied to multitarget arrays to remove some multiple access inter- ferences. After that the received signal is subjected to wavelet de-noising to reduce some noise, and used in CMA adaptive iteration for signal separation. Simulation results showed that the proposed algorithm performed better than the traditional CMA algorithm. 展开更多
关键词 Constant modulus algorithm Adaptive array Wavelet de-noising multiuser detection CDMA
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Efficient multiuser detector based on box-constrained deregularization and its FPGA design
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作者 Zhi Quan Jie Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第2期179-187,共9页
Multiuser detection can be described as a quadratic optimization problem with binary constraint. Many techniques are available to find approximate solution to this problem. These tech- niques can be characterized in t... Multiuser detection can be described as a quadratic optimization problem with binary constraint. Many techniques are available to find approximate solution to this problem. These tech- niques can be characterized in terms of complexity and detection performance. The "efficient frontier" of known techniques include the decision-feedback, branch-and-bound and probabilistic data association detectors. The presented iterative multiuser detection technique is based on joint deregularized and box-constrained so- lution to quadratic optimization with iterations similar to that used in the nonstationary Tikhonov iterated algorithm. The deregulari- zation maximizes the energy of the solution, this is opposite to the Tikhonov regularization where the energy is minimized. However, combined with box-constraints, the deregularization forces the solution to be close to the binary set. We further exploit the box- constrained dichotomous coordinate descent (DCD) algorithm and adapt it to the nonstationary iterative Tikhonov regularization to present an efficient detector. As a result, the worst-case and aver- age complexity are reduced down to K28 and K2~ floating point operation per second, respectively. The development improves the "efficient frontier" in multiuser detection, which is illustrated by simulation results. Finally, a field programmable gate array (FPGA) design of the detector is presented. The detection performance obtained from the fixed-point FPGA implementation shows a good match to the floating-point implementation. 展开更多
关键词 multiuser detection dichotomous coordinate descent (DCD) box-constrained DCD deregularization Tikhonov regular- ization low complexity field-programmable gate array (FPGA).
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Successive quadratic programming multiuser detector
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作者 Mu Xuewen Zhang Yaling Liu Sanyang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第1期8-13,共6页
Based on the semidefinite programming relaxation of the CDMA maximum likelihood multiuser detection problem, a detection strategy by the successive quadratic programming algorithm is presented. Coupled with the random... Based on the semidefinite programming relaxation of the CDMA maximum likelihood multiuser detection problem, a detection strategy by the successive quadratic programming algorithm is presented. Coupled with the randomized cut generation scheme, the suboptimal solution of the multiuser detection problem in obtained. Compared to the interior point methods previously reported based on semidefmite programming, simulations demonstrate that the successive quadratic programming algorithm often yields the similar BER performances of the multiuser detection problem. But the average CPU time of this approach is significantly reduced. 展开更多
关键词 Code division multiple access multiuser detection Semidefinite programming Successive quadratic programming.
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Algorithm and application of multiuser detection for CDMA-based MANET
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作者 钱小聪 郑宝玉 +1 位作者 颜振亚 余根坚 《Journal of Shanghai University(English Edition)》 CAS 2007年第2期148-152,共5页
Throughput of mobile ad hoc network (MANET) is limited by collision avoidance. In CDMA-based MANET, this limitation can be overcome by multiuser detection (MUD) because conventional colliding packets can be detach... Throughput of mobile ad hoc network (MANET) is limited by collision avoidance. In CDMA-based MANET, this limitation can be overcome by multiuser detection (MUD) because conventional colliding packets can be detached and detected by MUD so that multi-packet reception (MPR) is possible. This paper introduces the principles of MUD algorithm for MANET, and proposes an adaptive blind MUD algorithm. A special medium access control (MAC) protocol is designed to make MANET more efficient. This is achieved by sending more packets to a destination simultaneously. The proposed MUD algorithm and MAC protocol allow CDMA-based MANET to support MPR. Simulations show a remarkable improvement in the throughput performance of MANET. 展开更多
关键词 ad hoc mobile ad hoc network (MANET) multiuser detection CDMA
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Novel space-time multiuser detection algorithm of WCDMA system
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作者 ZhangXiaofei XuDazhuan YangBei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第1期42-46,共5页
The structure and performance of space-time multiuser detection receiver at base stations of WCDMA system is analyzed, in which smart antenna is employed. WCDMA uplink signal model is established in this paper. Space-... The structure and performance of space-time multiuser detection receiver at base stations of WCDMA system is analyzed, in which smart antenna is employed. WCDMA uplink signal model is established in this paper. Space-time multiuser receiver presented in this paper combines 2D-RAKE with parallel interference cancellation (PIC), and the improved parallel interference cancellation methods are given. A novel space-time multiuser detection scheme, 2DRAKE-GPPIC is proposed. This scheme employs smart antenna to suppress unexpected DOA (Direction Of Arrival) signal, uses RAKE receiver to combine different delays of expected signal, and utilizes grouped partial parallel interference cancellation (GPPIC) algorithm to suppress further the interference signal in the main lobe of array antennas. The simulation results reveal that the scheme of space-time multiuser detection presented in this paper has better performance for WCDMA system. 展开更多
关键词 WCDMA multiuser detection Multiple access interference Bite error rate Space-time processing.
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Improved Blind Multiuser Detection Algorithm Based on Minimum Output Energy
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作者 刘婷 张立毅 陈雷 《Transactions of Tianjin University》 EI CAS 2012年第6期450-455,共6页
Based on minimum output energy,an improved blind multiuser detection algorithm is proposed by the use of Hopfield neural network.Compared with traditional algorithms,the proposed algorithm does not need the circuit fo... Based on minimum output energy,an improved blind multiuser detection algorithm is proposed by the use of Hopfield neural network.Compared with traditional algorithms,the proposed algorithm does not need the circuit for constraints.The resources are greatly saved and the complexity is reduced as well.The simulation results show that the performance of the improved algorithm is similar to that of the optimal multiuser detection algorithm which is not suitable for the mobile station.Compared with the traditional gradient blind multiuser detection algorithm,the convergence speed of the improved algorithm is quickened. 展开更多
关键词 multiuser detection minimum output energy (MOE) Hopfield neural network energy function constrained optimization
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Space-Time Multiuser Detection for DS-CDMA Communication in MIMO Systems
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作者 单红梅 胡光锐 《Journal of Shanghai University(English Edition)》 CAS 2005年第4期344-348,共5页
Space-time signal processing based on multiple-input multiple-output(MIMO) systems is an active research field in which interfering signals are cancelled and multiuser detection is achieved using space diversity. In... Space-time signal processing based on multiple-input multiple-output(MIMO) systems is an active research field in which interfering signals are cancelled and multiuser detection is achieved using space diversity. In a Rayleigh fading channel, space-time block cedes using multiple transmitting antennas can improve system performance and reduce bit-error-rate for multiuser detection. In this paper, several antenna configurations are designed for DS-CDMA communication in MIMO systems. Space-time linear multinser detection and space-time serial interference cancellation multiuser detection are simulated. Bit-error-rate and computation complexities of the two methods are compared. Conclusions are given in the end. 展开更多
关键词 DS-CDMA multiple-input multiple-output(MIMO) space-time block codes space-time multiuser detection.
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A Particle Filter of Blind Equalization and Multiuser Detection in Asynchronous DS/CDMA Systems
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作者 张静 董建萍 张谦 《Journal of Donghua University(English Edition)》 EI CAS 2008年第3期263-268,共6页
The particle filter (PF) is proposed to be the asynchronous direct-sequence code-division multiple-access (DS/CDMA) multiuser detector without knowing the channel state information. The PF performs symbol detectio... The particle filter (PF) is proposed to be the asynchronous direct-sequence code-division multiple-access (DS/CDMA) multiuser detector without knowing the channel state information. The PF performs symbol detection according to the joint posterior density probability of simulated particles including relative delays, fading gains and symbols via sequential importance sample and resample. A simplified scheme is also proposed by separating the indepent relative delays and fading with symbols. These parameters are modeled as the extended aggressive processes and estimated by the Kalman filter, so as to provide their arbitrary distribution for symbol detection. Simulation results show that the bit error rate of the PF is less than conventional detectors. Moreover, the complexity of PF is moderate comparable to other nonlinear suboptimal approaches. 展开更多
关键词 code-division multiple-access CDMA) spread spectrum multiuser detection interference suppression channel estimation sequential Monte Carlo particle filter
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NOVEL DECODING OF SQUARE QAM MODULATED MIMO SYSTEMS BASED ON TURBO MULTIUSER DETECTION
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作者 Zheng Jianping Bai Baoming Wang Xinmei 《Journal of Electronics(China)》 2008年第2期174-178,共5页
By introducing the bit-level multi-stream coded Layered Space-Time (LST) transmitter along with a novel iterative MultiStage Decoding (MSD) at the receiver, the paper shows how to achieve the near-capacity perform... By introducing the bit-level multi-stream coded Layered Space-Time (LST) transmitter along with a novel iterative MultiStage Decoding (MSD) at the receiver, the paper shows how to achieve the near-capacity performance of the Multiple-Input Multiple-Output (MIMO) systems with square Quadrature Amplitude Modulation (QAM). In the proposed iterative MSD scheme, the detection at each stage is equivalent to multiuser detection of synchronous Code Division Multiple Access (CDMA) multiuser systems with the aid of the binary representation of the transmitted symbols. Therefore, the optimal Soft-Input Soft-Output (SISO) multiuser detection and low-complexity SISO multiuser detection can be utilized herein. And the proposed scheme with low-complexity SISO multiuser detection has polynomial complexity in the number of transmit antennas M, the number of receive antennas N, and the number of bits per constellation point Me. Simulation results demonstrate that the proposed scheme has similar Bit Error Rate (BER) performance to that of the known Iterative Tree Search (ITS) detection. 展开更多
关键词 Multiple-Input Multiple-Output (MIMO) MultiStage Decoding (MSD) Iterative detection/decoding multiuser detection Polynomial complexity
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A new support vector machine based multiuser detection scheme
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作者 王永建 赵洪林 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第5期620-623,共4页
In order to suppress the multiple access interference (MAI) in 3G, which limits the capacity of a CDMA communication system, a fast relevance vector machine (FRVM) is employed in the multiuser detection (MUD) scheme. ... In order to suppress the multiple access interference (MAI) in 3G, which limits the capacity of a CDMA communication system, a fast relevance vector machine (FRVM) is employed in the multiuser detection (MUD) scheme. This method aims to overcome the shortcomings of many ordinary support vector machine (SVM) based MUD schemes, such as the long training time and the inaccuracy of the decision data, and enhance the performance of a CDMA communication system. Computer simulation results demonstrate that the proposed FRVM based multiuser detection has lower bit error rate, costs short training time, needs fewer kernel functions and possesses better near-far resistance. 展开更多
关键词 multiuser detection support vector machine relevance vector machine bit error rate
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Iterative Multiuser Receiver Based on Decorrelating Decision-Feedback Detection
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作者 张爱萍 罗汉文 王好星 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第1期86-91,共6页
Iterative multiuser receiver for joint multiuser detection and channel decoding improves the receiver' s performance by passing soft information between multiuser detection and channel decoding. In this paper, an ... Iterative multiuser receiver for joint multiuser detection and channel decoding improves the receiver' s performance by passing soft information between multiuser detection and channel decoding. In this paper, an iterative multiuser receiver based on decorrelating decision-feedback detection is proposed, which is effective to implement multiuser detection, channel decoding and parameter estimation. The data decoding and the parameter estimation are reinforced each other. The bit error rate decreases along with the increase of the iteration, and the parameter estimation approaches the optimum at the same time. 展开更多
关键词 multiuser detection Parameter estimation Turbo principle.
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SUCCESSIVE BEAMFORMING,MULTIUSER DETECTION AND DIVERSITY RECEPTION FOR MULTICARRIER DS-CDMA SYSTEM WITH ANTENNA ARRAY
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作者 Yang Wei Chen Junshi +1 位作者 Tan Zhenhui Cheng Shixin 《Journal of Electronics(China)》 2007年第5期607-612,共6页
Code-Division Multiple-Access (CDMA) systems are interference limited,and therefore efficient interference management is necessary to enhance the performance of a CDMA system.In this paper,a successive beamforming (sp... Code-Division Multiple-Access (CDMA) systems are interference limited,and therefore efficient interference management is necessary to enhance the performance of a CDMA system.In this paper,a successive beamforming (spatial filtering),linear decorrelating MultiUser Detection (MUD, temporal filtering) and diversity reception structure for uplink multicarrier Direct Sequence CDMA (DS-CDMA) system with antenna array are proposed.By beamforming,the antenna array suppresses interference according to the distinct array signature.Subsequently,linear decorrelating MUD is ap- plied to separate the signals of different users and eliminate Multiple Access Interference (MAI).Finally, the decorrelated signals at different subcarriers that belong to the same user are combined to achieve frequency diversity.Simulation results show that the proposed structure offers significant Bit Error Rate (BER) performance improvement by successively exploiting the space-time-frequency processing. 展开更多
关键词 Antenna array Multicarrier Direct Sequence Code-Division Multiple-Access (DS-CDMA) multiuser Detection (MUD) Diversity
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