多路直扩信号并行IMPA捕获算法仿真实现

Simulated Realization of Multiple DS/SS Signals Parallel IMPA Acquisition

针对长PN序列作扩频地址码的多路直扩信号的快速捕获问题,提出多路直扩信号并行IMPA(迭代信息传递算法)捕获方案,该方案能够根据接收信号的信道信息直接生成与各路接收信号序列粗同步的本地伪码序列,改变了传统捕获方法中本地伪码序列的生成方式,大大缩短了信号的捕获时间。详细说明了该方案的实现原理和实现方法,并对该方案进行了仿真和实际验证。结果表明该方案能够在低信噪比下实现多路直扩信号的快速捕获,而且实现的复杂度较低。

The acquisition of a longer period PN codes for DS/SS system is of importance. A scheme for multiple DS/SS signal acquisition using IMPA （Iterative Message-passing Algorithm） on graphs is proposed,which can realized rude synchronism between received signal and local PN sequence directly and shorten the average acquisition time greatly. The principle and realization of this scheme are described in detail. Simulation adn validation of the scheme are carried out, the results of simulation show that this scheme can realized fast acquisition of multiple DS/SS signals and improve performance of acquisition in a condition of low SNR. And also the scheme is easier realized.