基于盲源分离的CDMA多用户检测与伪码估计

The Multi-User Detection and Chip Sequence Estimation for CDMA System Based on the Blind Source Separation

在分析DS-CDMA系统模型的基础上,提出一种基于盲源分离技术的用户扩频码盲估计算法.仿真结果表明,该算法在单径或多径环境中都能正确地估计不同用户的扩频码信息.同时还提出一种基于盲源分离技术的盲多用户检测算法,该算法利用不同用户信息之间的独立性,不仅不需要知道用户的扩频码和信道信息,而且其性能相对传统的匹配滤波和解相关算法有很大改善,当信噪比为6dB时,本文算法的误码率降低了两个数量级.

An algorithm on the blind estimation of the users＇ chip sequence based on blind source separation technology is presented on the analysis of the DS-CDMA system model. Simulation results show that the algorithm can estimate the chip sequence of the different users accurately on the single or multiple path circumstance.At the same time,a blind multi-user detection algorithm based on blind source separation technology is also presented, which not only need not know the users＇ chip sequence and channel information, but also make full use of the independence of different users. Therefore the performance of this multi-user detection algorithm presented in the paper is greatly improved relative to the traditional match filtering and de-correlation algorithm. When the signal to noise ratio（SNR） is equal to 6dB, the bit error rate（BER）of the algorithm presented is decreased by 2 orders of magnitude.