Ultrahigh-resolution agile SAR satellite sliding spotlight mode system parameter design method

Abstract

The invention relates to an ultrahigh-resolution agile SAR satellite sliding spotlight mode system parameter design method, is applicable to flexible realization of the ultrahigh-resolution imaging SAR satellite sliding spotlight mode system parameter design through whole satellite attitude, and belongs to the technical field of overall design of SAR satellites. According to the method, an accurate orbit, an earth model, system restriction factors, and imaging work characteristics of the sliding spotlight mode are fully considered, an ultrahigh-resolution agile SAR satellite sliding spotlight mode system parameter design method is provided, and an economic and high-efficiency realization method is provided for the ultrahigh-resolution satellite-borne SAR imaging; and the criterion of uniform-beam footprint ground slide speed is employed, ground aiming points of all moments within the whole imaging time are designed, parameters such as the attitude requirement and PRF at an instantaneous moment are calculated, and compared with the conventional method for calculating the parameters according to the mode far away from ground virtual aiming points, the method is higher in precision and imaging efficiency.

Description

technical field [0001] The invention relates to a method for designing system parameters of an ultra-high-resolution agile SAR satellite sliding beamforming mode system, which is suitable for the parameter design of a SAR satellite sliding beamforming mode system that realizes ultra-high-resolution imaging through the attitude maneuver of the entire satellite, and belongs to the overall design of SAR satellites In the technical field, the super high resolution means that the resolution of the SAR satellite is better than 0.4m, that is, less than 0.4m. Background technique [0002] The sliding spotlight mode is a novel SAR working mode, which slows down the sliding speed of the antenna beam footprint on the ground by controlling the scanning speed of the antenna beam, increases the synthetic aperture time of the imaging point, and realizes high-resolution imaging. The azimuth imaging range of the sliding beamforming mode is larger than that of the traditional beamforming mode...

AI Technical Summary

Problems solved by technology

This method is still calculated based on the principle of the virtual rotation center and the geometric relationship between the straight star and the earth, and the accuracy is not suitable for high-resolution SAR satellites

In addition, when using agile SAR satellites to achieve ultra-high resolution sliding spotlight mode imaging, the required satellite attitude angle needs to be given, and the above two methods are not applicable

Finally, the ultra-high-resolution spaceborne SAR sliding spotlight mode echo signal has a large distance migration, which makes it difficult to select a PRF. The above method cannot solve this problem

[0004] Agile SAR satellites achieve ultra-high-resolution sliding spotlight mode imaging through whole-star attitude maneuvers. The traditional method of calculating azimuth parameters based on the principle of virtual rotation center and the geometric relationship between the straight star and the ground cannot meet the needs of high-resolution sliding spotlight mode imaging.

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