一种新的抗远近效应的盲DS-CDMA接收机

A New Near Far Resistant Blind DS CDMA Receiver

本文研究多径频率选择性衰落信道下直接序列扩频码分多址 (DS CDMA)信号的处理问题 ,提出了一种新型的盲接收机 .该接收机不需预知多址干扰用户的扩频码 ,不需预知信道参数 ,只需已知期望用户的扩频码和粗略的定时 ,就可以完成用户的盲检测 .同时 ,该接收机通过降维自适应去相关滤波和基于判决指导的自适应多径合并 ,来获得低成本和良好的抗衰落、抗远近效应性能 .仿真结果验证了本文提出的接收机的优良性能 .

The problem of signal processing for direct-sequence code-division-multiple-access (DS-CDMA) signal over multipath frequency-selective mobile channels is considered.A new blind receiver is proposed.Without the knowledge of the multiple-access interference users′ spreading code and the channel characteristics,the receiver achieves blind detection with prior knowledge of only the desired users′ spreading code and approximate timing.By using reduced rank adaptive decorrelating filter and adaptive multipath combiner which is based on decision-directed algorithm,the receiver gets the ability to combat both fading and the near-far effect at low cost.Simulation results demonstrate that the proposed receiver offers high performance.