Research On TWR Combined Dictionary Sparse Imaging Method Under Wall Fuzzy Parameters

The traditional through-wall radar imaging method usually uses the position of the wall of the detection environment as a priori condition when detecting the hidden target behind the wall.In fact,this treatment is not applicable in engineering applications.In the actual environment,the position parameters of the wall are usually unknown.The assumption of the wall position by experience will reduce the accuracy of the target reconstruction position.For this reason,the wall-through radar imaging method when the wall position parameter is unknown is studied.The target detected by the through-wall radar has two states: static and motion,and it has more research value for the positioning and reconstruction of the moving target.After analysis,the echo signal of the moving target has block sparsity characteristics,so this thesis proposes a moving target through-wall radar algorithm with unknown wall parameters.The algorithm can image the moving target and the stationary target while accurately estimating the position parameters of the side wall.It is proved by experiments that the method can achieve high-resolution imaging of the moving target while efficiently estimating the wall parameters.When the electromagnetic wave emitted by the radar is transmitted in the detection space,the scatterer of the wall,the ground and the ceiling is present in the space,so that the echo signal of the detection target is reflected by the scatterer to generate multipath effect.If the multipath information in the target echo is not processed,many false targets appear in the reconstructed image,which affects the resolution and positioning accuracy of the reconstructed image of the detected target.The traditional multipath effect processing algorithm suppresses the multipath information and reduces its influence on the reconstruction target.In fact,the multipath signal contains some valid information.If these useful information are utilized,the reconstructed image can be further improved.Therefore,this thesis proposes a multipath development method to improve the reconstructed image quality of the multipath signal.The effectiveness and reliability of the algorithm are verified by simulation experiments.