Method and system for on-orbit calibration of electric axis of spaceborne terahertz detector antenna

Abstract

The invention discloses a method and a system for on-orbit calibration of the electric axis of a satellite-borne terahertz detector antenna. The on-orbit calibration method includes the following steps: select a radio star, and set the reference antenna electrical axis; based on the selected radio star, determine the antenna on-orbit pattern and the relationship between each frequency band by receiving the signal of the radio star. Relative relationship, to calibrate the antenna electrical axis of each frequency band; according to the relative relationship between the antenna electrical axis of each frequency band and the reference reference antenna electrical axis, the relative relationship between the antenna electrical axes of each frequency band is obtained, and then the output of each frequency band The relative calibration relationship between the electrical axes of the antenna. The invention can avoid the error introduced by atmospheric attenuation and interference, and can calibrate the electric axis of the antenna with wide frequency spectrum and multiple frequency bands synchronously.

Description

technical field [0001] The invention relates to an on-orbit calibration method for an antenna electric axis of a spaceborne terahertz detector, and a corresponding on-orbit calibration system, which belongs to the technical field of satellite remote sensing. Background technique [0002] For microwave loads, antenna pointing accuracy is an important factor affecting the application of microwave detection data, which not only directly affects the accuracy of the geolocation of the observation target, but also has an important impact on the radiation calibration accuracy of the detection data. In particular, with the improvement of application requirements and technical processes, large-diameter antennas have gradually changed from ground-based detection to spaceborne detection. How to ensure the antenna pointing accuracy of large-diameter antennas in complex space environments is still a key issue that needs to be solved. [0003] For spaceborne terahertz detectors, the accu...

AI Technical Summary

Problems solved by technology

The calibration process is mainly carried out in the ground-fixed coordinate system, and the atmospheric interference between the satellite terminal and the observation station during the propagation affects the calibration results. The shortcomings are: 1) The calibration results of the antenna pointing , its essence is not the calibration of the antenna itself, but a calibration of the deviation of the antenna itself coupled with various effects such as atmospheric interference and ground system errors; 2) the calibration results can only be limited to the distance between the ground fixed receiving station and the satellite The calibration of the antenna pointing between the antenna and the calibration result cannot be applied to the calibration between the antenna and other ground observation stations; it cannot be applied to the calibration of the antenna axis under other orientations.

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