空时编码(STC)技术将天线阵列信号处理和信道编码技术联合起来实现无线信道容量的有效增加。为了抑制空时分组编码(STBC)系统的共道用户干扰,对低复杂度的多用户检测算法进行研究,该文提出了一种STBC系统的迭代(turbo)多用户接收机。该接收机由一个软入软出(SISO)基于均值的软判决多用户检测器(Soft Decision Multi.User Detector,SDMUD)和一组SISO Turbo信道解码器构成。两者之间通过迭代交换外信息,精确地估计用户信号。仿真结果表明这种接收技术经3次迭代后性能改善约2dB,并且系统性能会随着接收天线的增多而得到明显提高,从而大大增加系统容量。
Space-Time Coding (STC) techniques, which combine antenna array signal processing and channel coding techniques, are very promising approaches to substantial capacity increase in wireless communications. In order to restrain the interference of co-channel users using Space-Time Block Coding (STBC), the anti-interference techniques is becoming a hot issue and the so-called "turbo multi-user detection" is applied in flat-fading channels. During iterations, extrinsic information is computed and exchanged between a soft decision multi-user detector (SDMUD) and a bank of turbo decoders, to achieve successively refined estimates of the users' signals. The simulations show that the proposed iterative receiver provides significant performance improvement over conventional noniterative methods around 2dB in both single-user and multi-user STBC systems. Furthermore, multi-user space-time processing techniques offer substantial performance gains by using more receive antennas.