Research On Multipath Signal Modeling And Radar Target Localization Method Based On Ray Tracing

Ground-based target detection radar is an important means of information acquisition in the urban environment.However,in actual urban detection scenarios,due to the occlusion of the urban building structure,the target to be detected is often in the blind area of radar detection,which makes traditional direct-view detection ineffective.The multipath propagation of electromagnetic waves is used to detect scenes that are not directly viewing urban areas.Nowadays,the kinds of radar systems are rich,and the geometric and electromagnetic characteristics of the non-line-of-sight environment in urban areas are also different.The lack of universal radar multipath signal modeling methods brings difficulties to the study of typical multipath utilization problems,such as the radar localization methods of non-line-of-sight target and the optimization of radar disposition in non-line-of-sight areas.Therefore,this article focuses on the abovementioned problems in the multipath utilization related fields of urban scenes,and the specific research work is as follows:Regarding the lack of a multi-path modeling method with high integration and wide applicability in the detection of non-direct-view targets in urban areas,this paper proposes a radar multipath signal propagation model suitable for urban scenes based on the idea of ray tracing.This paper first analyzes possible radar multipath signal propagation mechanisms and corresponding propagation characteristics in typical urban scenes,expounds the applicability of ray tracing ideas for multipath signal modeling,and builds universal applicability based on ray tracing method Radar multipath signal propagation model.The simulation experiment analyzes the propagation characteristics of different radar systems in different urban scenes,and compares them with the calculation results of commercial computing software.The results show that the calculation results of the proposed model are more accurate and can provide theoretical guidance for multipath utilization scenarios with different requirements in practice.In view of the different multipath propagation characteristics of different radar systems in urban scenes,the positioning algorithm design needs to be targeted,this paper selects two types of high-frequency and low-frequency two typical radar systems,designs corresponding localization methods for non-line-of-sight targets according to the number of available multipaths.For high-frequency radars where one-time multipath is available,the target angle information is extracted by using the arrival time difference of the onetransmit and two-receive radar,and then the range information is combined to achieve target position.For low-frequency radars where multiple multipaths are available,the multipath propagation model is used to calculate the path dictionary,and then match the actual echo path to achieve target position.Simulation experiments verify the applicability and effectiveness of the proposed method in actual complex urban scenes.Aiming at the gaps in the research on the optimization of radar stations in the nonline-of-sight detection scene in urban areas at this stage,this paper uses the proposed multipath propagation model to quantitatively calculate the energy coverage of the radar in non-line-of-sight scenes,analyzes the factors affecting site deployment from the perspective of energy detectability,proposes the coverage performance index of radar in non-line-of-sight scenes,and the optimal radar station location under a given scenario and demand is determined based on the principle of optimal comprehensive index.The simulation experiment shows that the proposed method has certain guiding significance for the actual radar deployment.