STBC-OFDM系统自适应加权并行多用户检测  

Parallel Multi-user Detection with Adaptive Weighting for STBC-OFDM Systems

作　　者：林静[1] 甘良才[1] 

机构地区：[1]武汉大学电子信息学院,武汉430079

出　　处：《应用科学学报》2010年第6期561-566,共6页Journal of Applied Sciences

基　　金：国家自然科学基金(No.61072041;No.60496310)资助

摘　　要：针对多用户空时块码正交频分复用系统,提出了基于Turbo码的自适应加权并行多用户检测方法.该方法利用自适应加权多用户检测进行多用户信号分离,并将所获得的软比特信息作为Turbo码的先验信息进行译码,将译码所得的外信息作为下次迭代中自适应加权多用户检测中权值的先验信息.数值仿真结果表明:采用该方法的空时块码正交频分复用系统收敛较快,与自适应部分并行多用户系统、实验加权多用户系统、传统并行干扰抵消多用户系统进行比较,分别可获得1.8 dB,2.5 dB和3 dB的增益.By exchanging information between Turbo decoding and multi-user detector,an iterative algorithm for adaptive weighting parallel multi-user detection is proposed.The method is applied to space time block coded orthogonal frequency division multiplexing（STBC-OFDM） systems.Multi-user signals are separated using the algorithm,and the obtained soft bit information is used as the prior information for Turbo decoding. The extrinsic information obtained in Turbo decoding is then used as a priori information for weighting coefficients in the next iteration of adaptive weighting multi-user detection.Simulation results show that the proposed method converges rapidly in space time block coded OFDM systems.Compared with adaptive partial parallel multi-user detection,trail-and-error multi-user detection,and the conventional parallel interference cancellation multi-user detection,the proposed technique offers gains of 1.8 dB,2.5 dB and 3.0 dB respectively.

关 键 词：STBC-OFDM系统 多用户检测 自适应加权 

分 类 号：TN911.72[电子电信—通信与信息系统]