Compressive sensing theory-based Doppler ambiguity-resolution processing method

Abstract

The invention discloses a compressive sensing theory-based Doppler ambiguity-resolution processing method, which comprises the following steps of: (1) performing non-uniform sampling on continuous echo pulses in a totally-coherent processing period by utilizing Q-fold pulse repetition frequency values; (2) designing the possible Doppler frequency range of a target, and ensuring the Q-fold pulse repetition frequency values do not have Doppler dead zones in the Doppler frequency range; (3) constructing a compressive sensing (CS) model by utilizing the time-domain under-sampling characteristics of sampled data in the totally-coherent processing period and the sparse characteristics of frequency spectrums of the target to be detected in the possible Doppler frequency range; and (4) resolving the CS model by utilizing an orthogonal matching pursuit (OMP) reconstruction algorithm to directly estimate the amplitude response of ambiguity-free Doppler spectrums. The method eliminates the restriction of the PRF multiplicity adopted by a radar system to the number of the targets to be detected, and simultaneously avoids the condition of false values caused by the influence of measurement errors in the conventional methods by taking the influence of noise on reconstruction results into account and performing de-noising operation when the CS model is resolved to estimate the amplitude response of the ambiguity-free Doppler spectrums by adopting the OMP reconstruction algorithm.

Description

Technical field [0001] The invention belongs to the field of target detection, and relates to a Doppler defuzzification processing method based on compressed sensing theory. Background technique [0002] Pulse Doppler (PD) technology has good clutter suppression performance and has been widely used in radars, especially in airborne radars. According to different needs, PD radar can adopt low repetition frequency, medium repetition frequency and high repetition frequency. Among them, there is no distance ambiguity in the low repetition mode, but there is generally serious Doppler (velocity) ambiguity for air targets. In order to obtain reliable target distance measurements during detection, ground and shipborne long-range radars generally use low repetition frequency methods, and airborne PD radars also generally use low repetition frequency methods under top-level conditions. In order to obtain a more accurate target radial velocity measurement value, the low repetition frequen...

AI Technical Summary

Problems solved by technology

A common defect of these methods is that for the defuzzification of N targets, at least N+1 different PRF values ​​are required, and each target is required to be detectable under at least N+1 PRFs, so that the target to be detected The number is limited by the PRF multiplicity used by the radar system

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