干扰环境下直扩系统中DMF捕获性能研究

基于数字匹配滤波器(DMF)的捕获电路具有较快的捕获速度,因此它在直扩系统(DSSS)中得到了广泛的应用。为了在干扰环境下进一步提高其捕获性能,本文对影响捕获性能的检测概率和虚警概率进行了分析;并对直扩系统中基于DMF的平均捕获时间进行了计算机仿真,从而找到了在平均捕获时间较小时应该满足的信干比、干噪比和判决门限,为改善直扩系统的捕获性能提供了理论依据。

Research on Acquisition Performance of DMF in DSSS Under the Condition of Interference

The acquisition circuit based on the digital matchedfilter(DMF)has become more and more applicable to direct sequence spread spectrum system(DSSS)because it can accelerate the process of PN code acquisition.In order to improve further its acquisition performance under the interference condition,the detection probability and false alarm probability which affect the acquisition performance of PN code are analyzed in this paper.Then,the mean acquisition time based on DMF in DSSS is simulated by using computer;and SJR,SNR and decision threshold with the condition of smaller mean acquisition time to be satisfied are ultimately found.It turns out that our works provide the theory basis to get the better acquisition performance in DSSS.