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Performance of multiuser CDMA system with space-time block coding in MIMO Rayleigh fading channels

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Science in China(Series F) 2009年第12期52卷 2296-2307页

作者： YU Xiangbin DONG Tao bi guangguo College of Information Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China School of Information Science and Technology Sun Yat-sen University Guangzhou 510275 China National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China

In this paper, by introducing orthogonal space-time coding scheme, the multiuser CDMA systems with different space time codes are given, and corresponding system performance is investigated over Rayleigh fading channel. A low-complexity multiuser receiver scheme is developed for space-time coded CDMA systems. The scheme can make full use of the complex orthogonality of space-time coding to simplify the high decoding complexity of the existing scheme. Compared to the existing scheme with exponential decoding complexity, it has linear decoding complexity. Based on the performance analysis and mathematical calculation, average bit error rate （BER） of the system is derived in detail, and tight closed-form approximation expressions of BER are attained. Simulation results on average BER are in agreement with the theory analysis. The results show that the proposed scheme can achieve almost the same performance as the existing scheme. Moreover, on the condition of same system throughput and concatenation of channel code, the given full-rate space-time coded CDMA system has lower BER than the full-diversity space-time coded CDMA systems.

关键词： space-time block coding code division multiple access (CDMA) full diversity full rate multiple input multiple output (MIMO)

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A novel rate-2 full diversity algebraic space-time code

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Frontiers of Electrical and Electronic Engineering in China 2009年第4期4卷 371-377页

作者： Xiufeng JIN guangguo bi National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China

Orthogonal space-time block codes(OSTBCs)have attracted considerable attention due to their low complexity linear decoding and full diversity in Rayleigh fading ***,OSTBCs exist only for certain numbers of transmit antennas and do not provide full code rate when more than two transmit antennas are *** this paper,a novel rate-2 algebraic space-time code that combines coordinate-interleaving and group precoding is *** properly choosing the designed parameters,the coding scheme can achieve full diversity order and high coding *** receiver adopts polynomial complexity sphere decoding algorithm to get maximum likelihood(ML)*** and simulations illustrate that the new code exhibits significant performance gain over the conventional OSTBCs and diagonal algebraic space-time code.

关键词： space-time coding coordinate-interleaving group precoding full diversity

Joint-state differential detection algorithm and its application in UWB wireless communication systems

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Science in China(Series F) 2007年第6期50卷 897-904页

作者： ZHANG Peng bi guangguo CAO XiuYing National Mobile Communication Research Laboratory Southeast University Nanjing 210096 China

In this paper, a novel concept of the joint state of input and output of encoder is proposed. Based on it, a recursive algorithm that implements the multi-symbol differential detection in criterion of maximum likelihood is proposed. Simulation results show that its performance can approach to the theoretical boundary of multi-symbol differential detection without increasing the complexity per symbol, and it is effective in practical systems. It is also an optimal algorithm to solve the problems of estimating the state sequence of finite-state Markov process observed in memoryless noise.

关键词： differential detection maximum likelihood joint state iteration

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Performance of orthogonal STBC-MIMO with variable-power adaptive modulation and delayed feedback in Nakagami fading channels

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Science China(Information Sciences) 2013年第10期56卷 81-90页

作者： YU Xiangbin CHEN XiaoMin bi guangguo RUI Yun College of Information Science and Technology Nanjing University of Aeronautics and Astronautics National Mobile Communications Research Laboratory Southeast University Shanghai Advanced Research Institute Chinese Academic of Science

A variable-power(VP)adaptive modulation(AM)scheme with space-time block code(STBC)is developed in MIMO systems,and the corresponding performance is investigated in Nakagami fading *** optimum switching thresholds are derived so that the spectrum efciency(SE)under an average power and a target bit error rate(BER)constraint is *** the switching thresholds,average BER and SE are further *** a result,closed-form expressions are ***,the exact and approximate BER expressions of VP AM and constant-power(CP)AM systems with delayed feedback are respectively *** results show that the theoretical SE and BER can match the corresponding simulation *** results indicate that VP-AM with STBC provide higher spectrum efciency than the CP counterparts,and has slighter bite error rate performance degradation when the normalized delay is less than 0.01.

关键词： orthogonal space-time coding adaptive modulation variable power delayed feedback Nakagami fading

Efficient detection for cooperative communication with two alternating relays

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Frontiers of Electrical and Electronic Engineering in China 2010年第1期5卷 29-35页

作者： Mingwei CAO guangguo bi National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China

A two-path amplify-and-forward(AF)relaying scheme,which uses two relays to retransmit for the source alternately,was proposed by Rankov[Rankov et *** Journal on Selected Areas in Communications,2007,25(2):379–389].This scheme can avoid half-duplex loss in spectral efficiency,but it cannot work well when the interrelay channel gain is *** efficient detection scheme for two-path AF relaying system is proposed in this *** the proposed scheme,interference cancellation is first performed at the destination so that the received signal after interference cancellation is the superposition of two symbols with ***,a low complexity soft maximum a posteriori(MAP)decoder and an iterative soft decoder are employed to extract the diversity of the two relay-destination *** proposed detection scheme can efficiently improve the system performance compared to the detection scheme presented by Rankov(2007),especially when the inter-relay channel gain is strong.

关键词： cooperative diversity amplify-and-forward(AF) maximum a posteriori(MAP) iterative decoding

A design of multi-cycle detector for cognitive radios

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Frontiers of Electrical and Electronic Engineering in China 2011年第4期6卷 501-506页

作者： Jun WANG guangguo bi National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China

Cognitive radio(CR)is a promising *** most fundamental problem of CR is spectrum *** detector is often considered for spectrum sensing in CR,and if the noise power is exactly known,energy detector has admirable ***,in practice,noise power is always inexactly *** solve this problem,Dandawate[Dandawate et *** Transactions on Signal Processing,1994,42(9):2355-2369]has proposed a nonparametric single-cycle detector based on cyclostationarity,which is robust to noise *** this paper,based on Dandawate’s single-cycle detector,a joint multi-cycle detector is further proposed,which is also nonparametric and immune from noise *** results have shown the validity and superiority over single-cycle detector of the proposed detector.

关键词： cognitive radio(CR) cyclostationarity noise uncertainty spectrum sensing

Concatenated Alamouti codes using multi-level modulation and symbol mapping diversity technique

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Frontiers of Electrical and Electronic Engineering in China 2010年第4期5卷 464-469页

作者： Mingwei CAO guangguo bi China Ship Research and Development Academy Beijing 100192China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China

A family of space-time block codes(STBCs)for systems with even transmit antennas and any number of receive antennas is *** new codeword matrix is constructed by concatenating Alamouti space-time codes to form a block diagonal matrix,and its dimension is equal to the number of transmit *** Alamouti codes in the same codeword matrix have the same information;thus,full transmit diversity can be achieved over fading *** improve the spectral efficiency,multi-level modulations such as multi-quadrature amplitude modulation(M-QAM)are *** symbol mapping diversity is then exploited between transmissions of the same information from different antennas to improve the bit error rate(BER)*** proposed codes outperform the diagonal algebraic space-time(DAST)codes presented by Damen[Damen et *** Transactions on Information Theory,2002,48(3):628–636]when they have the same spectral ***,they outperform the 1/2-rate codes from complex orthogonal ***,compared to DAST codes,the proposed codes have a low decoding complexity because we only need to perform linear processing to achieve single-symbol maximum-likelihood(ML)decoding.

关键词： space-time block codes(STBCs) symbol mapping spectral efficiency decoding complexity pairwise error probability(PEP)

Joint signal detection algorithm of cognitive radio in UWB

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Frontiers of Electrical and Electronic Engineering in China 2009年第3期4卷 295-299页

作者： Hongjun WANG guangguo bi National Mobile Communication Research Laboratory Southeast UniversityNanjing 210096China Department of Information Electronic Engineering InstituteHefei 230037China

With the progress of research on cognitive radio in ultra-wideband(UWB)open frequency-band,a joint detection algorithm integrating the energy and bispectrum detection is proposed in detail for non-Gaussian signal detection from Gaussian *** performance of the algorithm was evaluated by simulation,the result of which indicates that the joint detection not only solves the problem of the signal detection in low signal-to-noise ratio(SNR)but also improves the operational speed and the detection ***,the joint detection algorithm has definite prospect in practice.

关键词： ultra-wideband(UWB) cognitive radio joint detection bi-spectrum estimation

SOME NEW RESULTS ON CORRELATION PROPERTIES OF SEQUENCES USED IN CDMA SYSTEMS

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SOME NEW RESULTS ON CORRELATION PROPERTIES OF SEQUENCES USED...