Micro-motion target defect echo high-resolution imaging method based on time-frequency dictionary

Abstract

The invention discloses a micro-motion target defect echo high-resolution imaging method based on a time-frequency dictionary, mainly to solve the problem that high-resolution imaging is hard to be carried out on a target with complex micro-motion and a target with data defects in the prior art. The realization scheme comprises steps: range compression processing is firstly carried out on micro-motion target defect echo data received by an inverse synthetic aperture radar; then, a short-time Fourier transform matrix for the echo is generated; then, a corrected augmented Lagrangian algorithm is used for calculating a time-instantaneous Doppler distribution for defect echo signals of each range unit; and finally, time-instantaneous Doppler distributions for all range units are stacked into a three-dimensional matrix, and a two-dimensional matrix at a different time is selected to generate a range-instantaneous Doppler image sequence for the target. Thus, an imaging result with good focusing can be acquired under a lower computational burden, and the method can be used for target recognition and radar target detection.

Description

technical field [0001] The invention belongs to the field of radar technology, and further relates to a high-resolution two-dimensional ISAR imaging method for micro-moving targets, which can be used for target recognition and radar target detection. Background technique [0002] With the rapid development of inverse synthetic aperture radar (ISAR), high-resolution ISAR imaging of micro-moving targets has become a new research direction in the field of radar imaging in recent years. For example, the engine blades of fixed-wing aircraft, the propellers of helicopters, the arms that swing when pedestrians walk, etc. Target fretting will produce sideband frequency modulations in addition to the subject Doppler frequency, known as micro-Doppler. Micro-Doppler is an inherent essential feature of a micro-moving target, which contains the structure and motion information of the target. When it is described by time-frequency analysis method, this complex frequency modulation will ...

AI Technical Summary

Problems solved by technology

Although this invention can achieve accurate phase compensation and data reconstruction in the case of maneuvering targets and sparse apertures, this method cannot achieve good focused imaging of complex micro-moving targets due to the traditional range-Doppler imaging method

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