Realization method of mosaic mode based on agile synthetic aperture radar satellite attitude maneuver

Abstract

The invention provides a mosaic mode implementation method based on agile SAR (synthetic aperture radar) satellite attitude maneuvering, and the method comprises the steps: calculating total parameters for achieving the mosaic mode imaging; calculating the parameters of a central imaging subblock of an image formed by the mosaic mode imaging; gradually increasing the imaging subblocks based on the central imaging subblock, and calculating the parameters of the imaging subblocks till the obtained azimuth imaging of the image meets the demands. Therefore, the method gives full consideration to a precise track and an earth model, designs an aiming point and working time sequence of an agile SAR satellite according to the mosaic mode demand performance indexes and imaging geometry, obtains the beam pointing direction needed by imaging through the lateral rolling and pitching maneuvering of the whole satellite, controls the direction of a ground footprint of a radar beam through the yaw maneuvering of the whole satellite, and achieves the quick switching of the beam in a range direction through electric scanning. The method guarantees the seamless joint between different image sublocks in the mosaic mode, and provides an economical and high-efficiency implementation solution.

Description

technical field [0001] The invention relates to a mosaic mode realization method based on agile synthetic aperture radar (hereinafter referred to as SAR) satellite attitude maneuvering, and is especially suitable for realizing the mosaic mode by agile SAR satellites adopting centralized feeding reflector system. Background technique [0002] The mosaic mode is an emerging SAR working system. In the range direction, the antenna beam is switched between different sub-swaths to achieve wide swath imaging, and in the azimuth direction, the beam is scanned in reverse to achieve high-resolution imaging. Its working principle is as follows: figure 1 shown. The mosaic mode combines the features of the wide swath of the ScanSAR mode and the high resolution of the spotlight mode, so the mosaic mode is also called the spotlight version of ScanSAR. The agile SAR satellite relies on the attitude control system to control the satellite as a whole to swing around the three axes of pitch, ...

AI Technical Summary

Problems solved by technology

At this time, the rotation of the ground footprint of the beam causes the switching between sub-swaths to be carried out only along different oblique directions, and finally the overall image of the mosaic mode presents an inverted trapezoid, and there is a gap in the azimuth direction, which cannot achieve seamless splicing (such as image 3 shown)

Images