摘要
针对高动态、大频偏的扩频系统采用了一种基于快速傅氏变换(FFT)算法的伪码快速捕获方法,该捕获方法是在搜索伪码相位的同时,通过频率扫描的方式搜索载波频率偏移值,将原来的伪码相位、载波频偏的二维搜索过程变成只搜索伪码相位的一维搜索过程,从而大大减少了高动态、大频偏扩频系统中的同步伪码的搜索的复杂度。理论分析和仿真结果都证实在不增加硬件复杂度的情况下,基于FFT算法的伪码快速捕获方法能够大幅度地缩短捕获时间,降低系统复杂度。
A PN code acquisition method combined with frequency acquisition based on fast Fourier transform(FFT) algorithm is presented. While the phase of PN code is being searched, carrier frequency offset could also be acquired. So this method could reduce two dimensions search of PN code phase and carrier frequency offset to one dimension search of PN code phase, which could greatly reduce code acquisition time in high dynamic environment. Theoretical analysis and simulation results have verified that it could radically reduce the acquisition time and improve the acquisition performance without additional hardware complexity.
出处
《现代防御技术》
北大核心
2012年第2期150-154,共5页
Modern Defence Technology
关键词
扩频系统
频域相关
快速捕获
快速傅氏变换(FFT)算法
spread spectrum system
frequency domain correlation
quick acquisition (capture)
fast Fourier transform (FFT) algorithm