Multiuser Receiver Scheme for a Full-Rate Space-Time Block Coded CDMA System
Yu Xiang-bin①; Dong Tao②; Xu Da-zhuan①②; Bi Guang-guo②
①Information and Communication Engineering Postdoctoral Research Station, Nanjing University of Aeronautics
and Astronautics, Nanjing 210016, China;②National Mobile Communications Research Lab., Southeast University, Nanjing 210096 China
Abstract：By introducing full-rate Space-Time Block Coding (STBC) scheme, a Full-rate Space-Time Block Coded CDMA (FSTBC-CDMA) system model is given in this paper. Considering that existing space-time coded CDMA system has high decoding complexity, a low-complexity multiuser receiver scheme is also proposed. The scheme can make full use of the complex orthogonality of STBC to simply the high decoding complexity of the existing scheme after multiuser detection method like is employed to suppress multiuser interference effectively; it has linear decoding complexity when compared with existing scheme (it has exponential decoding complexity). Moreover, compared with full-diversity space-time block coded CDMA, the FSTBC-CDMA system can implement full rate, low complexity and partial diversity, has more spatial redundant information. Thus the concatenation of channel coding can effectively compensate for the performance loss due to partial diversity. Simulation results also show that on the condition of same system throughput and concatenation of channel code, the proposed FSTBC-CDMA system has lower Bit Error Rate (BER) than those low-rate and full-diversity space-time block coded CDMA system.
2007, Vol. 29 
