Millimeter wave short-range target detection method based on composite frequency modulation continuous waves

Abstract

The invention discloses a millimeter wave short-range target detection method based on composite frequency modulation continuous waves. The method is high in efficiency and good in real-time performance. The method comprises the following steps: (10) millimeter-wave radar signal transmission: constructing frequency-modulated continuous waves of four target waveforms, and transmitting the frequency-modulated continuous waves as millimeter-wave radar transmission signals; (20) echo signal frequency mixing and filtering: carrying out frequency mixing, sampling and filtering on echo signals and the transmitted signals; (30) difference frequency signal spectrum peak value detection: performing fast Fourier transform and peak value detection on discrete signals, and obtaining echo difference frequency signal peak value frequency corresponding to each segment of target waveform through peak value search; and (40) composite waveform target detection: synthesizing the echo difference frequency signal peak frequency corresponding to each segment of target waveform to obtain a combined target distance velocity matrix, a velocity matrix and a distance matrix; removing false targets in the combined target distance velocity matrix; removing false targets in the combined target distance velocity matrix; and obtaining distance and speed information of a real target.

Description

technical field [0001] The invention belongs to the field of target detection, in particular to a millimeter-wave short-range target detection method based on composite frequency-modulated continuous waves. Background technique [0002] Millimeter-wave short-range target detection is based on millimeter-wave proximity technology, which enables the detection of target distance and velocity information within tens of centimeters to several kilometers. Due to the high spatial resolution, strong anti-interference ability, high distance resolution, strong penetrating ability and low transmission power of millimeter-wave radar, it is widely used in the field of millimeter-wave short-range target detection, such as gunfire homing, fuze, target detection and Military fields such as tracking, civilian fields such as intelligent security, automobile collision avoidance and automatic control. [0003] Millimeter wave radar is mainly divided into pulse system radar and continuous wave ...

AI Technical Summary

Problems solved by technology

[0005] In order to solve the problem that triangular wave FM continuous wave radar will produce false targets in multi-target detection scenarios, trapezoidal wave FM continuous wave radar combines the characteristics of triangular wave FM continuous wave and constant frequency continuous wave, using the triangular wave band to obtain combined targets, using the constant frequency band The obtained multi-target radial velocity information removes false targets in the velocity dimension, but in some scenarios, all false targets cannot be removed

[0006] Considering the problem that the above-mentioned system radar cannot eliminate all false targets in some scenarios, the current mainstream algorithm is to transmit two segments of triangular waves with different FM slopes of the up and down frequency bands, and the distance and speed information of the real target will not follow the up and down frequency. The characteristics of the change of the FM slope of the sweep band are changed to remove false targets

This algorithm can effectively eliminate all false targets, but assuming that there are N targets, 2*N 4 The tolerance comparison of the secondary distance dimension and velocity dimension, so the algorithm has the disadvantages of high complexity and poor real-time performance

[0007] Therefore, the problem existing in the prior art is that the millimeter-wave short-range target detection method based on variable-period triangular wave frequency-modulated continuous wave has poor real-time performance due to the high complexity of the algorithm.

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