Abstract:

Recently, the PN code acquisition algorithm based on the adaptive filter theory has been more and more studied. Using this idea, a new Doppler frequency shift acquisition algorithm based on adaptive filters in the frequency field is proposed. With the two issues, an acquisition algorithm combining the PN code acquisition and the Doppler frequency shift is followingly derived. In addition, aiming at eliminating the effect of the modulation data on the traditionally adaptive filter PN acquisition algorithm, a differentially adaptive algorithm is introduced, where the effect of polarity reversion caused by data modulation on the PN code is removed, resulting in the applicability spreading of this kind of PN code acquisition algorithm. Finally, the proposed algorithm is validated by simulation.

Key words: adaptive filter;PN code acquisition;Doppler frequency shift