Method for detecting observed quantity validity in navigation receiver

Abstract

A method for detecting observed quantity validity in a navigation receiver mainly includes: S1. calculating a carrier-to-noise ratio of a signal; S2. judging stability of carrier tracking; S3. Extracting carrier Doppler frequency observed quantity of a carrier tracking loop and pseudo-range observed quantity of a code tracking loop in each epoch; S4. utilizing the two kinds of observed quantity to calculate a pseudo-range difference of corresponding two successive epoch respectively; S5. calculating a difference value of the pseudo-range differences and comparing with a threshold, thereby judging whether pseudo-range observed quantity of the current epoch is correct; S6. summing a difference of delta pseudo ranges of the current epoch and differences of delta pseudo ranges of n previous epochs, comparing with a threshold, and judging whether pseudo range observed quantity is correct; and S7. performing the abovementioned steps on each satellite which keeps tracking, collecting all signals of satellites whose observed quantity is judged to be correct, and inputting the signals to a positioning resolving module. The method provided by the invention does not need redundant information, and solves the problem of positioning stability of a receiver in complex environment with a relatively small calculated amount.

Description

technical field [0001] The invention relates to a baseband signal processing algorithm of a navigation receiver, in particular to a method for detecting the validity of an observation quantity output by a tracking loop in the navigation receiver. Background technique [0002] The internal structure of the navigation receiver is usually divided into three functional modules: radio frequency (RF) front-end processing, baseband digital signal processing (DSP) and positioning and navigation calculations, according to the order of the workflow. Among them, the RF front-end processing module receives the signals of all visible satellites through the antenna, and down-converts the L-band signal to the intermediate frequency (or close to the baseband), then performs sampling and quantization, and inputs the digital intermediate frequency signal to the baseband processing module; the baseband digital signal The processing part mainly captures and tracks visible satellite signals, per...

AI Technical Summary

Problems solved by technology

[0006] The technical problem to be solved by the present invention is to provide a new method for detecting the validity of observations in a navigation receiver, which overcomes that the lock discriminator in the prior art can only detect the performance of the tracking loop and cannot detect the overall pseudorange The correctness, based on the detection of redundant information in the positioning calculation, requires at least 5 satellites to determine whether the positioning is valid, and 6 satellites to eliminate wrong observations, and the algorithm is complex and the calculation is large.

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