A adaptive acquisition algorithm, based on coherent correlation model and FFT,is presented for DS/SS navigation signal under low signal to noise ration. By this algorithm , the S/N after testing is improved and acquisition time is become shorted. The simulation results of GPS C/A signal acquisition indicated that the performance of this algorithm is better than non coherent correlation, about 2 dB gain is gotten and the signal -175 dBW at sensitivity level can be acquired. This algorithm is applicable to tracking and precise measurement of PN phase of satellite position and DS/SS ranging signals.
