路径相关抗多径多用户检测器

提出了一种新的抗多径多用户检测器，该检测器能有效地实现多径分集。为简化异步多用户检测，作者曾提出过一种新的异步直扩码分多址（ＤＳ－ＣＤＭＡ）系统，即无记忆ＤＳ－ＣＤＭＡ系统，并对该系统在单用户多径情况下的性能以及几种新的抗多径检测器（单用户）进行了研究。同时考虑了多径干扰和多址干扰的影响。利用同一用户的多径信号间的强相关特性，并进行简化，将在实现路径分集的同时抑制多址干扰的影响并降低运算复杂度。虽然简化会带来附加的干扰项，理论分析和计算机仿真都表明，该路径相关多用户检测器（ＰＣＭＵＤ）具有比传统的ＲＡＫＥ接收机好得多的抗多径多址干扰性能。另外，该检测器具有很小的复杂度，能很好地工作在总的路径数超过扩频增益时。

Anti-multipath path-coherence multiuser detector (PCMUD)

This paper puts forward a new multiuser detector named path coherence multiuser detector (PCMUD) which works in the multipath environment and can implement the multipath combination very effectively. The high coherence between multipath signals of the same user is utilized and a simplification is introduced to cut down the computation complexity as well as implement multipath combination. Although additional interference arises when it introduces such simplification, the theoretical analysis and computer simulation both show that this anti multipath PCMUD has superior performance compared with conventional RAKE receivers and other multiuser detectors in DS CDMA systems with multipath interference, especially when the offset between different paths of the same user is less than the half of the duration of one symbol. Furthermore, this new detector works well with quite small cost of computation when the number of the signals from all the considered paths exceeds the processing gain while some other detectors, such as other linear detectors, can not work.