Estimation method of micro-motion characteristics of low-frequency radar target

Abstract

The invention provides a long frequency band radar target jogging feature estimation method. The technical scheme is that a target narrow band echo obtained by a low frequency band radar is subjected to N point discrete sampling to obtain discrete signals, then complex logarithm operation is performed on the discrete signals, phase modulation signals are obtained by phase ambiguity resolving and are subjected to frequency spectrum estimation, and a target jogging spectrum is obtained by calculating, so the jogging feature of the target is obtained. The long frequency band radar target jogging feature estimation method is suitable for a low frequency radar small-amplitude jogging target, the estimation precision of jogging parameters is high, applicable systems have wide frequency bands and the signal to noise ratio demand is low.

Description

technical field [0001] The invention belongs to the technical field of radar, in particular, the invention relates to a method for estimating the micro-motion characteristic of a radar target by using the micro-Doppler signal analysis process of the low-frequency radar echo. Background technique [0002] The micro-motion feature is one of the main features adopted by the radar target recognition system. The micro-movement characteristics of the target, such as vibration, precession, and rotation, contain fine and stable favorable features and information. Once extracted, they can be used as an important basis for identification. etc. are of great significance. The micro-Doppler frequency of the radar target is proportional to the center frequency of the radar and the micro-motion amplitude of the target. When the radar wavelength is comparable to or longer than the micro-motion amplitude of the target, the micro-Doppler modulation amplitude of the radar target is reduced. ...

AI Technical Summary

Problems solved by technology

The micro-motion estimation method based on the time-frequency distribution, in order to ensure that the micro-motion characteristics can be extracted reliably, the wavelength of the radar should be at least smaller than the micro-motion amplitude of the target, so it cannot be applied to the low-frequency radar micro-motion estimation problem

The model-based parameterized estimation method not only has a large amount of computation, but it is difficult to realize in engineering applications, and the target micro-motion is regarded as the ideal form of the standard sine. Under the conditions of non-ideal scattering characteristics or complex micro-motion forms, the target micro-motion cannot Doppler signal processing

The book "The Micro-Doppler Effect in Radar[M]" (Artech House, 2011) pointed out that because the radar wavelength is long, it is very difficult to extract small-scale micro-Doppler modulation, and the problem of extracting small-scale micro-Doppler modulation has not yet been solved

Within the scope of the information we have, there is still a gap in the field of small-scale and complex micro-motion characteristic estimation technology for low-frequency radar targets.

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