关键词: 四分法, 比特跳变位估计, 弱信号捕获, 差分相干累加

Abstract:

In order to solve the inability of the traditional satellite signal acquisition algorithm to meet the practical requirements under the condition of BD weak signals,a novel algorithm based on FFT is proposed,which uses the differential coherent accumulation method and estimates the position of the navigation data bit-flip by the Quartering algorithm.With a high data utilization ratio,this method is robust to the noise as well,as compared with the algorithm with alternating half bits and combination coherent accumulating.The simulation result shows that the proposed algorithm can capture the weak signal in BDS under 38 dB SNR and can improve the software receiver sensitivity.

Key words: quartering;bit-flip;capture the weak signal;differential coherent accumulation