Target positioning method based on high-low-orbit bistatic InSAR system

Abstract

The invention discloses a target positioning method based on a high-low-orbit bistatic InSAR system. The method comprises the following steps of: obtaining the observation geometry of the high-low-orbit bistatic InSAR system, specifically, establishing a high-orbit satellite position vector, a low-orbit master satellite position vector, a low-orbit auxiliary satellite position vector, a point target position vector, slant distance vectors from a high-orbit satellite, a low-orbit master satellite and a low-orbit auxiliary satellite to a point target, a low-orbit master satellite speed, a low-orbit auxiliary satellite speed, and baseline vectors from the low-orbit master satellite to the high-orbit satellite and the low-orbit auxiliary satellite of the high-low-orbit double-base InSAR systemunder an earth-centered earth-fixed coordinate system; obtaining a positioning equation set according to the observation geometry of the high-low-orbit bistatic InSAR system; and obtaining a closed-form solution of the positioning equation set to determine the position coordinate result of the point target. The target positioning method is faster in calculation speed and higher in precision.

Description

technical field [0001] The invention belongs to the technical field of signal processing, and in particular relates to a target positioning method based on a high- and low-orbit dual-base InSAR system, which is suitable for using the transmission signal emitted by a high-orbit SAR satellite as an active irradiation source, and the level of ground scattering signals received by a LEO SAR double-star formation Positioning technology of orbital bistatic InSAR system. Background technique [0002] Spaceborne Interferometric Synthetic Aperture Radar (InSAR) can obtain high-resolution and high-precision Digital Elevation Model (DEM, Digital Elevation Model), which is currently a research hotspot in earth remote sensing. Generally, spaceborne InSAR can be realized through three systems: single-satellite repeating orbit system, single-satellite dual-antenna system, and dual-base system. The single-satellite repeat orbit system is realized by repeating the orbit of a single satellit...

AI Technical Summary

Problems solved by technology

[0005] However, in the high and low orbit dual-base InSAR positioning, due to the significant difference between the observation geometry and the traditional low orbit formation InSAR, it is impossible to directly obtain the slant distance from the low orbit main star to the point target. The main star slant distance equation in the traditional InSAR positioning equation is also derived from the spherical equation becomes the ellipsoid equation and so on

Therefore, the existing low-orbit formation satellite InSAR positioning algorithm is no longer suitable for high-low orbit dual-base InSAR positioning

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