LFMCW radar detection moving human body target method based on human body model

Abstract

The invention provides an LFMCW radar detection moving human body target method based on a human body model. The method comprises the steps that analog-to-digital conversion is carried out on an LFMCW radar echo beat signal; FFT processing is carried out on each PRI echo beat datum to acquire the LFMCW radar echo beat signal frequency domain data when a human body slowly moves, and rearranging is carried out in a slow time-distance domain two-dimensional plane; a Boulic human body walking model is constructed; according to the human body moving gait frequency and an initial phase range, a number of human body trunk moving models with different parameters are constructed on a gait frequency-initial phase two-dimensional plane; an LFMCW radar echo nonlinear phase compensation signal is reconstructed, and phase compensation is carried out on the rearranged data; FFT processing is carried out to acquire a four-dimensional space processing result; whether a target is in a distance unit is judged through constant false-alarm detection processing; and the information of distance, velocity and gait frequency of the target are acquired in the presence of the target. According to the invention, the signal-to-noise ratio of LFMCW radar detection is improved, and the human body target detection performance in strong ground clutter is improved.

Description

technical field [0001] The invention belongs to the technical field of radar information detection, in particular to a method for detecting a moving human target by a human body model-based LFMCW radar. [0002] technical background [0003] In the radar system, target detection is one of the most important tasks. Linear Frequency Modulation Continuous Wave (LFMCW) radar has unique characteristics such as small size, light weight, high distance resolution, no distance blind zone and strong anti-intercept ability. Advantages, in ground reconnaissance scenarios, it can be used to detect moving targets such as enemy personnel, vehicles and tanks, and obtain information such as the distance, speed and orientation of the target. [0004] In the actual environment, due to the large radar cross section (Radar Cross Section, RCS) and fast movement speed of vehicles, tanks and other targets, LFMCW radar can be easily detected. However, for the detection of slow and weak targets on th...

AI Technical Summary

Problems solved by technology

However, for the detection of slow and weak targets on the ground such as people, the technical difficulty is very great. The bottleneck mainly lies in: 1) This type of targets are mostly located in complex strong ground clutter, and have the characteristics of small reflection coefficient and large RCS fluctuation. lead to a weak radar detection capability for such targets

2) There is a serious overlap between the human slow target and the ground clutter spectrum (especially the motion clutter) in the Doppler domain. The Doppler channel of the fast target makes the target echo and the ground clutter aliased, and it is difficult to distinguish the target and the clutter from the Doppler dimension.

These micro-Dopplers are distributed on both sides of the average radial velocity of the human body, resulting in the spread of Doppler after long-term coherent accumulation, so that the energy of the target signal cannot be fully accumulated

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