Research On High-precision Positioning Method Of Space Multispectral Gaze Camera

Image registration techniques for detecting targets in space require high temporal resolution and multispectral images to improve the target detection probability and reduce the false positive rate.Normally,the satellite and the payload are calibrated in the laboratory.However,due to the influence of gravity changes,solar radiation and temperature field changes during the satellite launch,the calibration parameters in the laboratory will change with unpredictable changes.Therefore,space geometric positioning of the camera is of great significance.In this paper,the geometric positioning method of multi-band cameras is studied and the research on image registration method between different spectral segments is conducted.At present,the registration method based on image information has been developed,and image registration accuracy is affected by the effective number of common multispectral registration control points as well as its stability.Image registration based on stellar trajectory measurement can be used to perform modifications of registration deviation caused by thermal distortions during satellite launch.This study proposes a new image registration method based on the detection of stars by using the stellar trajectory on a camera's focal plane.A generated 12?12 data template and the Lagrange interpolation method are used in the registration model.Multispectral image registration based on stellar trajectory fitting can achieve highprecision image registration among different spectra.Before the registration,there are 2 to 7 pixel random deviations in image point data between different spectral.The errors between the coordinate points obtained by registration and the corresponding coordinate points in the original image are mainly distributed in the range of 0.05 to 0.5 pixels.The method achieves a good registration effect.In this paper,the method of calculating and calculating the space geometric positioning model of the camera is studied.Based on the principle of camera imaging,a series of coordinate system transformations are performed by using the position of the star point acquired in the image plane coordinate system and finally projected to the celestial sphere coordinate system.The corresponding declination of the right ascension in celestial coordinates is calculated.The results are compared with the declination of stellate declination in star database to determine the location accuracy.The method can obtain high positioning accuracy.