Abstract：To solve the IF signal capture problems in the software GPS receiver, first the parallel code acquisition algorithm based on FFT is used to achieve the coarse frequency of IF signal and obtain the fine frequency based on the use of FFT in frequency domain analysis.The acquisition decision is dependent on the ratio of the maximum peak and the subpeak ratio,at the same time,the specific steps are presented. Through the analysis of the real GPS IF signal, experimental results show that the FFTbased GPS signal acqusition and FFT frequencydomain method are very effective to obtain the fine frequency,this is,can capture quickly and accurately,so to meet the requirements of GPS software receiver.
