Bistatic SAR channel equalization method based on echo data

Abstract

The invention discloses a bistatic SAR channel equalization method based on echo data, aiming at solving the problem that the traditional method only equalizes the channel amplitude-phase inconsistency caused by a receiver, and the channel amplitude-phase inconsistency caused by an antenna feed line cannot be equalized due to mechanism reasons. The method performs range compression on echoes of areference channel and a channel to be equalized, compensates for the fixed phase difference of strong point target echoes caused by the inconsistency of the receiver channel position, and estimates the equalizer coefficients by the recursive least squares algorithm, so that the equalization filter is constructed. Finally, the echoes of the channel to be equalized are equalized by the equalizationfilter. The method directly processes the echoes passing through the channel to be equalized, does not need to obtain the equalization filter coefficient by using the training sample in advance, and avoids the influence of environment and time variation.

Description

technical field [0001] The invention belongs to the technical field of radar, in particular to a bistatic SAR channel equalization technology. Background technique [0002] Synthetic Aperture Radar (SAR) is an all-weather, all-weather modern high-resolution microwave remote sensing imaging radar, which uses the relative motion between the radar antenna and the target area to obtain high spatial resolution. Synthetic aperture radar has played an increasingly important role in the fields of terrain surveying and mapping, vegetation analysis, ocean and hydrological observation, environment and disaster monitoring, resource exploration, and detection of small changes in the earth's crust. [0003] Bistatic SAR is a new radar system, the system transmitting station and receiving station are placed on different platforms. Compared with single-base SAR, it has the advantages of rich target information, long range, good security, and strong anti-interference ability, making it an i...

AI Technical Summary

Problems solved by technology

In Document 1, it is necessary to inject broadband chirp signals into each receiving channel for adaptive filtering to generate weight coefficients, and then let the echoes be re-equalized by the equalizer, which is greatly affected by the environment and time, and it can only affect the output of the receiver. Amplitude and phase mismatch for equalization

Document 2 does not consider the problem of echo phase space variation in its compensation phase, and there is a phase error

Images