为了提高定位精度和满足C/A码不可用的场合,文中提出了GPS(globalpositioningsystem)中基于频域FFT的P码直接快速捕获方法,并对不同信噪比情况下的峰值检测结果进行了Matlab仿真分析,接受信号较弱时,则采用视频累积方法。仿真结果表明,基于频域FFT的P码直接快速捕获方法可行。通过理论分析,与传统的滑动相关法相比,这种快速捕获方法的捕获时间缩短了十倍以上,捕获运算量也大大减少。

In order to increase positioning accuracy and meet the application where C/A code is unavailable, the direct P-code acquisition is useful. A fast P-code acquisition in GPS based on FFT was proposed and its performance was analyzed. The simulation and analysis results show, compared with conventional slipping correlation method, the capturing time of this fast P-code acquisition method is reduced more times, and the calculation is also reduced greatly. It has reference value for the other direct long pseudo random noise (PRN) code acquisition.