Instrument stellar magnitude estimation method for star sensor

Abstract

The invention relates to an instrument stellar magnitude estimation method for a star sensor. The method comprises the following steps of S1, preprocessing a real star point spot image; S2, performingdimension reduction filtering on the star point spot image, and extracting image characteristics of the star point spot image by utilizing Kalman filtering; S3, according to the characteristics of the star sensor, calculating the total number of photoelectrons generated by incidence of a star point; S4, traversing parameters according to a skewed normal distribution model of a star point spot, and establishing a relation database between the parameters and the image characteristics; and S5, based on the image characteristics obtained in the step S2, searching for the parameter with an optimalmatching error in the relation database obtained in the step S4, building the skewed normal distribution model, and performing simulation to obtain the star point spot image. The Kalman filtering isused for parameter estimation of a star point imaging model; a star point energy distribution model is optimized; the instrument stellar magnitude of the star sensor can be iteratively estimated in real time; the asymmetry of the star point spot is characterized; and the real-time performance and the accuracy of estimation are ensured.

Description

technical field [0001] The invention relates to a method for estimating magnitude of a star sensor instrument, belonging to the technical field of star sensor research. Background technique [0002] The star sensor is the attitude sensor with the highest precision at present, and it is widely used in the determination of satellite attitude. The star spot specifically refers to the photoelectric digital image of a single star generated by the star sensor collecting star light. The position of the star point can be obtained after a series of processing, extraction and algorithm calculation of the star point image spot, so the star point image spot has a huge impact on improving the performance of the star sensor such as accuracy. [0003] Most of the current research on star spots focuses on the star point extraction algorithm, and the research on the energy distribution model of star spots is not in-depth, and there is a lack of definite model parameters for specific stars a...

AI Technical Summary

Problems solved by technology

However, the model is relatively simple and cannot simulate asymmetric star spots, and the fitting accuracy of the actually generated asymmetric star spots is poor

In addition, there are also literatures that propose a star point image spot energy distribution model based on a skewed normal distribution, but there is no real-time method to determine the parameters of the model, that is, there is no real-time simulation of the star point of a certain star on a certain star sensor Spot method

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