Augmented state algorithm for pulsar azimuth error estimation

Abstract

The invention specifically discloses an augmented state algorithm for pulsar azimuth error estimation, and the algorithm comprises the following steps: building a pulsar time conversion model based on a solar system centroid coordinate system; selecting right ascension errors and declination errors of pulsar azimuth information as state variables, and establishing a state equation and an observation equation of a traditional pulsar azimuth error estimation algorithm in combination with a time conversion model; widening the satellite position error scalar, the clock error and the clock error drift rate into new state variables, and obtaining a state equation and an observation equation of an augmented state algorithm for pulsar azimuth error estimation, wherein the satellite position error and the clock error are considered in the algorithm at the same time; and utilizing a Kalman filtering algorithm to process a pulse arrival time observed quantity to obtain a state variable estimated value, and compensating system deviation caused by a satellite position error and a clock error in an algorithm estimation process so that pulsar azimuth error estimation precision is improved.

Description

technical field [0001] The invention relates to the field of pulsar azimuth error estimation, in particular to an algorithm for estimating pulsar azimuth error by using beacon satellites. Background technique [0002] X-ray pulsar navigation is a new type of autonomous navigation, which mainly relies on the detectors on the spacecraft to detect the radiation signals of pulsars, and compares them with the pulsar information obtained through long-term observations to realize the positioning of the spacecraft. Because it is completely passive, it has strong anti-interference ability, is not easily disturbed by human factors and other factors, has high stability, strong autonomy, and navigation error does not accumulate over time. However, there are still some problems that need to be solved urgently in pulsar navigation, such as weak pulse signal, long navigation filtering period, and influence of pulsar azimuth error. Among them, the pulsar azimuth error is an important reaso...

AI Technical Summary

Problems solved by technology

However, according to the currently published literature, the clock error in the process of pulsar azimuth error estimation has not yet been studied by scholars

At present, scholars have carried out a series of studies on the pulsar azimuth error estimation algorithm and achieved many results, but they have not considered the problem of clock error and satellite position error in the estimation process, which needs further research

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