Research On Wall Parameter Estimation And Target Detection Of UWB MIMO Radar

With its strong penetration,high range resolution and large detection range,UWB through-wall-radar has a wide application prospect in military and civil fields,and has become the mainstream equipment in the field of contactless detection.However,through-wall-radar will produce different delay and attenuation when penetrating the medium,which will reduce the accuracy of target detection.This paper studies the problem of wall parameter estimation and wall compensation.The main work and research results are as follows:(1)The effects of different parameters on echo delay and attenuation when UWB MIMO through-wall-radar penetrates uniform and nonuniform media are verified,and the signal theoretical models of uniform multi-layer wall and non-uniform multi-layer wall are constructed according to the propagation characteristics of electromagnetic wave in different media,providing a theoretical basis for subsequent research.(2)A wall classification method based on support vector machine and a parameter estimation method for different types of multi-layer walls are proposed.Firstly,in the aspect of wall classification,the time-delay characteristics of reflected echo at the dielectric boundary are trained and classified,and the echo data of three types of typical walls are simulated to verify the feasibility of this method;Secondly,combined with the theoretical model of multi-layer wall,the parameters of multi-layer wall are estimated based on the reflected echo time delay characteristics at the dielectric boundary under different antenna spacing.Simulation experiments verify the feasibility and correctness of the method in this paper.(3)Based on the theory of electromagnetic wave shortest delay path propagation,a non-uniform wall compensation method based on the improved shortest path algorithm is proposed.Firstly,the feasibility of this method in the uniform wall model is verified by simulation experiments.Then,according to the characteristics of the non-uniform wall model,the compensation method of the uniform wall is improved to be suitable for the non-uniform wall scene.Finally,the effectiveness of the method is verified by the simulation data without compensation,the original method compensation and the improved method compensation,and the target position offset.