A Novel Receiving Method for BOC Modulation

Abstract

The invention belongs to a novel receiving method for BOC modulation. A Beidou B3C signal modulated by BOC(15,2.5) is adopted, a local oscillator of 1210 MHz is configured on an 'FPGA+DSP' platform toenable a satellite navigation signal to be subjected to down-conversion to 58.52 MHz, then through an AD9266 chip, an undersampled signal of 78 MHz is moved to 19.48 MHz, and the 19.48 MHz intermediate-frequency satellite signal is captured and traced; at the stage of capturing, a subcarrier and a carrier are stripped together, although the code phase searching precision is only 0.5 chip, simpleness and universality are achieved; and at the stage of tracing, a three-loop structure of a carrier loop, a subcarrier loop and a code loop is adopted, the indrawing range of 0.5 chip can be borne, and the tracing sensitivity equivalent to that of a traditional tracing loop and the tracing precision higher than that of the traditional tracing loop are achieved.

Description

technical field [0001] The invention belongs to a signal processing method of a satellite navigation receiver, in particular to a novel receiving method for BOC modulation. Background technique [0002] The BOC modulation method is the satellite navigation modulation method that both Beidou and GPS will adopt in the future. Its characteristic is to add a subcarrier modulation link between the pseudo code modulation and carrier modulation of BPSK modulation, and move the spectrum of the satellite signal to the left and right sides of the center frequency point. , which can not only ensure that the carrier center frequency is shared with the early signal, avoid spectrum interference between systems, but also bring a larger Gabor bandwidth and improve the potential code tracking accuracy of the navigation signal. However, the autocorrelation function of the BOC signal has a multi-peak characteristic. Once the auxiliary peak is locked by mistake, a large code tracking error will...

AI Technical Summary

Problems solved by technology

[0002] The BOC modulation method is the satellite navigation modulation method that both Beidou and GPS will adopt in the future. Its characteristic is to add a subcarrier modulation link between the pseudo code modulation and carrier modulation of BPSK modulation, and move the spectrum of the satellite signal to the left and right sides of the center frequency point. , which can not only ensure that the carrier center frequency is shared with the early signal, avoid spectrum interference between systems, but also bring a larger Gabor bandwidth and improve the potential code tracking accuracy of the navigation signal. However, the autocorrelation function of the BOC signal has a multi-peak characteristic. Once the auxiliary peak is locked by mistake, it will cause a large code tracking error

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