A New Navigation Message Demodulation Algorithm for Satellite Navigation Receiver

Abstract

A new navigation message demodulation algorithm for satellite navigation software receiver is researched. The detailed phase and frequency information of the carrier are obtained by analyzing the phase angle of the DFT component of the satellite navigation IF signal, and navigation messages are demodulated by adjusting the initial phase of the adjacent data block is π flipped or not. The detailed implementation steps of the method are presented, and the reason of phase angle discontinuity of kernel function is analyzed and compensated. Finally, the method is verified by simulation and actual signal respectively and compared with the traditional phase-locked loop method. The results show that the carrier frequency accuracy of new algorithm can reach 10 Hz, more precise than traditional method; signal tracking can effectively output navigation message information, the method with data block processing to obtain the phase angle is more suitable for software radio ideas.