Micro-motion target time-frequency graph reconstruction method based on weighted ADMM

Abstract

The invention provides a micro-motion target time-frequency graph reconstruction method based on a weighted alternating direction multiplier method (ADMM), and solves the problems that in the prior art, a time-frequency dictionary is too large, so that the reconstruction speed of a time-frequency graph is low, and a soft threshold parameter is a fixed value, so that the focusing performance of a reconstructed graph is reduced. The method comprises the following steps: (1) acquiring a radar echo signal of a micro-motion target; (2) intercepting radar echo sub-signals; (3) generating a time-frequency dictionary; (4) generating a weighted vector of each sub-signal; (5) calculating a time-frequency distribution vector of each sub-signal; and (6) constructing a reconstruction time-frequency graph of the micro-motion target. According to the method, the unique time-frequency dictionary with a small scale is generated, the weighted alternating direction multiplier method ADMM is used for calculation, the reconstruction speed of the time-frequency graph is increased, and the focusing performance of the reconstructed graph is improved.

Description

technical field [0001] The invention belongs to the field of radar technology, and further relates to a time-frequency map reconstruction method of a micro-moving target based on a weighted alternating direction method of multipliers ADMM (Alternating Direction Method of Multipliers) in the field of radar signal processing technology. The invention can be used to reconstruct the time-frequency diagram of the micro-moving target, obtain the time-frequency diagram with good focus, and use it for the imaging of the micro-moving target and the feature extraction of the micro-moving target. Background technique [0002] Fretting refers to the vibration or rotation of the target or certain structures on the target that are independent of the main body movement, such as the rotation of helicopter blades, the spin, precession and nutation of ballistic targets, and the swing of limbs when walking. Micro-motion produces sideband frequency modulations around the main Doppler correspond...

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Problems solved by technology

[0005] The purpose of the present invention is to address the shortcomings of the above-mentioned prior art, and propose a time-frequency map reconstruction method for micro-movement targets based on the weighted alternating direction multiplier method ADMM, which is used to solve the problems caused by the excessively large time-frequency dictionary in the prior art. The cost is too high, the reconstruction speed is slow, and the soft threshold parameter used by the algorithm is a fixed value, which cannot adapt to the signal characteristics, and it is easy to filter out the signal characteristic information, resulting in a decrease in the focus of the reconstruction map.

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