Satellite space signal abnormity detection method and system

Abstract

The invention provides a satellite space signal abnormity detection method and system. The method comprises the following steps of: selecting a base station, constructing a pseudo-range observation equation of all satellites of the selected base station at a certain frequency point, and calculating a pseudo-range residual error corresponding to each satellite; judging whether the pseudo-range residual errors of all the satellites of the selected reference station at the frequency point meet the chi-square test or not, and if not, carrying out gross error detection on the pseudo-range residual errors of all the satellites of the selected reference station at the frequency point to identify abnormal satellites in all the satellites of the selected reference station at the frequency point, and repeating the step until chi-square test is finally met; repeating the steps until the identification information of all the satellites of all the reference stations at all the frequency points is obtained; and judging the health states of all the satellites according to the identification information.

Description

technical field [0001] This specification generally relates to the field of navigation technology, and in particular relates to a method and system for detecting anomalies of satellite space signals. Background technique [0002] The space signal error of the satellite can sometimes reach hundreds of thousands of meters, and when it is not marked, it will introduce dangerous misleading information into the navigation and positioning. In the standard positioning service, the GPS broadcast ephemeris broadcasts the health status identification of the satellite to inform the user of the health status of the current ephemeris. In fact, when the satellite health flag is available, due to the influence of the ground control part or the external environment of the satellite itself, the satellite signal in space (Signal In Space, SIS) anomaly will occur from time to time, which will lead to user ranging errors (User Range Error, URE) reaches tens of meters or even tens of kilometers...

AI Technical Summary

Problems solved by technology

[0005] 1. The existing method uses ionosphere-free combination to weaken the influence of various atmospheric errors. Such a combination will lose half of the original multi-frequency observations, and cannot monitor the abnormality of multi-system multi-frequency point signals

[0006] 2. The threshold tolerance is obtained by combining the GPS integrity standard system and the statistical distribution law of the broadcast ephemeris single-user instantaneous space signal user ranging error, but the precise ephemeris has a time delay of about 2 weeks, and the statistical results two weeks ago are used It is used to monitor the abnormality of real-time broadcast ephemeris, which will lead to misjudgment and missed judgment

Carrier smoothing requires initialization time, there is a window period for monitoring, and abnormal carrier information will also pollute the pseudorange, and the smoothing process will be interrupted when a cycle slip occurs or the carrier is abnormal; secondly, the calculation efficiency is low due to Kalman filtering. Low time delay cannot be guaranteed with a large number of base station inputs

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