Non-line-of-sight Target Multipath Detection Method Based On Millimeter Wave Radar

Concealed non-line-of-sight target detection and positioning technology has a wide range of applications in urban street fighting,security,and anti-riot.Since multipath propagation is less sensitive to electromagnetic transmission than multipath propagation,multipath detection is a practical way to achieve hidden non-direct vision target detection.In this paper,for the detection problem of hidden non-line-of-sight targets,multi-path echo modeling of concealed non-line-ofsight targets in typical urban architectural layout scenes,hidden non-line-of-sight target detection based on multi-path utilization,and concealment based on multi-path propagation Research work such as non-line-of-sight target positioning,the main contents are as follows:1.According to the urban layout of typical single buildings and L-shaped buildings,the electromagnetic propagation law is analyzed.The multi-channel millimeter-wave radar based non-line-of-sight hidden target multipath echo model is established.Finally,the antenna,wall and target are analyzed.Geometric relationship.2.In order to solve the problem of hidden non-line-of-sight target detection problem,the distance-speed monotone-frequency decoupling algorithm for slow-speed non-line-of-sight moving targets and the up-and-down frequency-distance-speed decoupling algorithm for fast nonline-of-sight moving targets are studied,and the distance is improved.The accuracy of parameter estimation for motions such as velocity is studied.Finally,the non-line-of-sight target detection algorithm based on CA-CFAR algorithm is studied.Compared with the fixed threshold detection algorithm,the algorithm is more applicable in non-line-of-sight environments.3.In order to achieve hidden human target location,combined with the multi-channel millimeter wave radar system,two common target localization algorithms are improved.Firstly,the hidden non-line-of-sight target localization algorithm based on dual antenna phase is analyzed.Then the algorithm is used to obtain the non-line-of-sight target phase information between each receive channel,and the non-line-of-sight target angle is calculated from the phase difference of the adjacent receive array elements.Finally,combined with the estimated distance and geometric information,the non-line-of-sight target is located.At the same time,based on the DOA azimuth estimation algorithm commonly used by small array elements,the algorithm is used to realize the location of the hidden non-line-of-sight target.Finally,the performance of the two positioning algorithms is compared under the same building layout.In summary,the algorithms described are verified by simulation or measured data.The measured data show that the proposed multipath detection method based on millimeter wave radar based on millimeter wave radar is feasible and easy to practice in engineering.