基于迭代信息传递的PN码快速捕获方法研究

Research on Rapid PN Code Acquisition Using Iterative Message-passing Algorithm

在扩频通信系统中,低信噪比情况下,长伪码序列的快速捕获成为急需解决的一个关键问题。为了解决该问题,提出一种基于迭代信息传递算法的伪码快速捕获方法,给出了该算法伪码快速捕获的原理和实现方法,仿真分析了该方法的捕获性能。该方法采用软件实现,实现的复杂度较低。仿真结果表明该方法具有较快的捕获速度,较高的捕获概率,并能够在低信噪比下稳定工作。

In spread spectrum system, quickly achieving long period PN codes is crucial when signal-to-noise ratio （SNR） is low. To solve the problem, we propose a new method of PN code acquisition using lterative Message-passing Algorithm and give the principle and realization of this method. The probability of acquisition and the average acquisition time are discussed in detail. This algorithm is fulfilled by software and the complication is reduced. The results of simulation show that this method can make the acquisition time greatly decreased and the performance of acquisition improved, when the SNR is low.