扩频信号基于FFT码捕获的计算量分析

摘要

Signal capture is the key of the spread spectrum system. Beginning with fast acquisition, the paper compares the theory of traditional capture method and fast capture method based on FFT, analyzes and compares the calculated amount of the different capture methods. The results show that the calculated amount of the fast capture method based on FFT is three orders of magnitude lower than that of the traditional capture method. This method saves much resource and time in the implementation of the hardware.%扩频通信技术中信号的捕获是扩频体制的关键.从快速捕获的角度出发,对传统捕获方法和基于FFT的快速捕获方法的原理进行了对比,并对不同捕获方法的计算量进行了分析和比较.获得基于FFT的循环相关捕获方法其计算量比传统方法少了3个数量级以上的结果.得到该方法在硬件实现中与传统滑动相关法相比大大节省了资源,减少了耗时的结论.