Bistatic ISAR Image Fusion Method Based on Subaperture Parameter Estimation

Abstract

The invention discloses a bistatic inverse synthetic aperture radar (ISAR) image fusion method based on sub aperture parameter estimation, which mainly solves the problem of low efficiency of the existing bistatic ISAR image fusion and has a realization process comprising the following steps of: building a bistatic radar turntable model; obtaining the target distance Doppler image of two radars; using the Doppler difference values of isolated strong scattering points at different sub apertures for estimating the target rotating angle speed; then, carrying out orientation calibration accordingto the obtained target rotation angle speed; estimating the half bistatic angle through the conversion relationship between coordinate systems; carrying out distance direction matching filtering and motion compensation on data of the two radars; then, adopting a back propagation (BP) algorithm for carrying out compensation on the echo phase according to the estimated half bistatic angle and the target rotating angle speed; and mapping the data of the radar 1 and the radar 2 after the compensation completion to the same rectangular coordinate system for carrying out coherent fusion. The theoretical analysis and experiment results show that the method of the invention can obtain images with better effects, can obtain more target information and can be used for target identification.

Description

technical field [0001] The invention belongs to the technical field of inverse synthetic aperture radar, and further relates to a bistatic inverse synthetic aperture radar image fusion method based on sub-aperture parameter estimation, which can obtain target images under multiple viewing angles and richer target information. Background technique [0002] Inverse synthetic aperture radar (ISAR) has the characteristics of all-weather, all-time and long-distance observation. It can perform high-resolution imaging and identification of targets, and obtain relevant information, which plays a key role in modern warfare. Compared with monostatic inverse synthetic aperture radar, bistatic radar has the characteristics of longer range, stronger anti-jamming and information acquisition capabilities. Through multiple radar systems, the target images obtained from different viewing angles are fused to obtain higher-quality images and richer target information. [0003] Many existing i...

AI Technical Summary

Problems solved by technology

This method adopts the single-base ISAR system of sending and receiving, which makes this method have many shortcomings in practical application:

[0005] 1. Due to the single-base ISAR model, its action distance is short, and its ability to resist interference and obtain target information is low;

[0006] 2. Due to the one-send-one-receive system, the system needs at least two transmissions and receptions to perform image fusion, and the image fusion efficiency is not high;

[0007] 3. Since the signals are not transmitted and received at the same time, the signal-to-noise ratio of the two images obtained is very low, and the image fusion quality is not high

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