%0 Journal Article
%A DU Qiu-ying
%A WU Ya-tong
%A ZHANG Wen-xu
%T Beidou Signal Capture Algorithm Based on Pseudo Code and Doppler Frequency Separation
%D 2019
%R 10.13190/j.jbupt.2018-008
%J Journal of Beijing University of Posts and Telecommunications
%P 35-40,108
%V 42
%N 1
%X Beidou B1 frequency signal using the secondary encoding structure, bit-flipping of Neumann-Hoffman (NH) codes used for secondary encoding leads to a decrease in receiver acquisition performance. Aiming at this problem, a Beidou signal acquisition algorithm based on pseudocode and Doppler frequency separation is proposed. The algorithm divides the received signal into two paths, and uses the delay difference operation and the bipolarity of the ranging code to process the two signals respectively, thus eliminating the influence of the bit hopping of the NH code. Based on this, the matched filter is used to capture the phase of the code and the fast Fourier transformation is used to search for the Doppler frequency. Capturing the phase and the Doppler frequency at the same time is realized. Finally, the simulation results show that the proposed algorithm successfully captures the signal with bit-flipping. Compared to partial matched filtering-fast Fourier transformation algorithm, the sensitivity is 1.03 dB increased under the same false alarm rate.
%U https://journal.bupt.edu.cn/EN/10.13190/j.jbupt.2018-008