Space-based radar space moving target detection and parameter estimation method and system

Abstract

The invention provides a space-based radar space moving target detection and parameter estimation method and system. The method comprises the steps that S1, radar echoes are preprocessed to obtain baseband echo signals; s2, a corresponding phase compensation function is constructed based on echo characteristics of Doppler ambiguity and Doppler distortion signals so as to eliminate influences of Doppler ambiguity and Doppler spectrum distortion in baseband echo signals at the same time; s3, Keystone transformation is performed on the baseband echo signal subjected to Doppler ambiguity and Doppler distortion elimination to complete linear range walk correction; s4, after distance correction is completed, an acceleration matched filter bank is constructed to eliminate residual distance curvature and Doppler spread; and S5, after range walk and Doppler spread correction are completed, two-dimensional Fourier transform is utilized to complete a final coherent accumulation result. Compared with a traditional Keystone transformation matched filtering method, the provided correction Keystone transformation matched filtering method can achieve coherent integration of the high maneuvering target under the condition that the signal-to-noise ratio is not reduced.

Description

technical field [0001] The present invention relates to the technical field of radar signal processing, in particular, to a space-based radar space moving target detection and parameter estimation method and system, and more specifically, to a space-based radar system for high-speed, high-maneuvering space moving targets under under-sampling. Base radar moving target detection and parameter estimation methods. Background technique [0002] With the rapid development of space exploration technology, space moving targets (SMTs) such as stealth aircraft, space debris, ballistic missiles, and hypersonic vehicles have gradually become a serious threat in the field of defense. The Spaceborne Radar (SBR) system can break through the constraints of the earth's curvature, domain, and airspace limitations of traditional ground-based / sea-based / space-based radar systems, and provide sufficient observation range and detection distance. It is a monitoring and early warning of space moving...

AI Technical Summary

Problems solved by technology

Among them, the GRFT method achieves coherent accumulation by simultaneously compensating for the range walk and Doppler phase changes caused by the relative motion of the radar and the moving target, which can provide the best detection performance, but it requires a large amount of calculation due to the multi-dimensional search, which is not conducive to real-time processing

In order to reduce the search dimension, the 2-D MF method constructs an acceleration-related matched filter function in the two-dimensional frequency domain, but it is only suitable for the detection of moving targets of large-azimuth time-width-bandwidth product signals; series inversion The method and the KTMF method overcome this defect, but the matched filtering process that requires one-dimensional search is still time-consuming; the ACCF method can significantly reduce the computational complexity, but due to the need for nonlinear operations, it will cause a certain SNR loss

[0004] In addition, for the SMT inspection of the SBR system, there is an additional issue to consider

In order to meet the needs of a large observation range, the pulse repetition frequency (PRF) of the SBR system has certain limitations; under the dual influence of low PRF and high maneuverability, the Doppler frequency of a space moving target can easily exceed the PRF, and even span multiple PRF, that is, Doppler ambiguity and Doppler aliasing coexist, this phenomenon will make existing target detection methods invalid or severely degrade their performance

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