Efficient GPS digital tracking method and GPS digital tracking ring

Abstract

The invention relates to the technical field of GPS, in particular to an efficient GPS digital tracking method. The efficient GPS digital tracking method is characterized in that in the tracking process, the center frequency of a carrier wave is separated from the center frequency of a C/A code, a tracking ring only tracks and adjusts Doppler frequency deviation, corresponding deviation phase step length is calculated through the Doppler frequency deviation, and then the deviation phase step length is compensated with the center phase step length corresponding to the center frequency. According to the efficient GPS digital tracking method, the Doppler frequency is smaller than the center frequency and the largest Doppler frequency is only 1/818 of the center frequency of the carrier wave, and the width of 10 bits can be saved; the largest Doppler frequency of the C/A code is only 1/255750 of the central frequency of the C/A code, and width of 18 bits is saved, computation complexity is reduced when respective phase step lengths are computed, and the synchronous speed and efficiency of the GPS tracking ring are improved.

Description

technical field [0001] The invention relates to the technical field of global positioning, in particular to an efficient GPS digital tracking method and a GPS digital tracking ring. Background technique [0002] At present, GPS is used more and more widely, and the premise that the terminal receiver uses GPS is that it can track GPS satellite signals correctly. Each satellite transmits a different coarse code (C / A code), and there is almost no interference between the satellite signals received by the receiver. Due to the relative motion between the satellite and the user, etc., there is a Doppler frequency shift in the carrier frequency of the GPS signal received by the receiver. [0003] figure 1 Shows the structure of the current GPS tracking loop, where 600 is the part of the current GPS carrier loop adjustment, and 700 is the part of the GPS code loop adjustment. figure 2 Shows the structure of the current GPS carrier loop adjustment, namely figure 1 The specific i...

AI Technical Summary

Problems solved by technology

[0022] The main purpose of the present invention is to provide a high-efficiency GPS digital tracking method, aiming to solve the problem that the prior art uses high-bit-width numbers to perform calculations, which will lead to low speed and low efficiency of GPS tracking loop synchronization

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