多径信道下的盲群多用户检测

Group-blind multi-user detection under multi-path channel

本文提出一种自适应盲群多用户检测算法,它可以在直扩CDMA下行链路中有效地抑制多址干扰(MAI)和符号间干扰(ISI)。通过在子空间内对接收符号的相关矩阵进行预处理,可以得到一个具有盲群约束条件的GSC(广义旁瓣消除)算法。通过理论分析可以看出:这种满足新的约束条件的GSC算法不仅可以有效地抑制多址干扰和符号间干扰,而且还可以从序列中提取有用的用户信息。通过仿真表明,改进后的GSC算法在无线多径信道下,可以带来良好的增益。

This paper proposes a new group-blind adaptive multi-user detector, which is suitable to eliminate multiple-access interference （MAI）, inter-symbol interference （ISI） in DS/CDMA downlink system. By performing the subspace approach on the correlation matrix of received signal, we propose an improved GSC （generalized sidelobe canceller） receiver with the new group constraint. The analysis indicates that the new group constraint not only retains the property of suppressing ISI and canceling MAI, but also can extract the useful information from the succeeding bit for the desired user. Simulations show that the improved GSC filter can cancel the MAI efficiently whether the wireless channel length is short or long, and has better performance than compared other filters.