Research On Three-dimensional Through-wall Imaging Based On Improved 3D-FFBP Algorithm

Through-Wall Imaging Radar(TWIR)utilizes the penetration characteristics of low-frequency electromagnetic waves to detect,locate,and image status of objects hidden in buildings,which greatly improves combat capabilities and counter-terrorism in urban areas.Personnel search and rescue capability in disaster rescue has become a research hotspot in recent years.The Impulse UltraWideband(IR-UWB)signal-based wall-through imaging system is mainly composed of two parts: modeling,simulation and imaging.This paper focuses on the IR-UWB signal propagation characteristics modeling and imaging issues.The research provides theoretical guidance for the design of practical systems and communication applications.In the modeling of wall-through characteristics,in order to improve the problems of the FDTD method in predicting the propagation of IR-UWB signals,such as the large memory resource consumption and the long computing time,this paper provides some solutions to the shortcomings of traditional FDTD methods.The MMP-FDTD and ADI-FDTD algorithm were used to model the analysis of the propagation characteristics of UWBW.The simulation results confirmed that the improved FDTD method can reduce the calculation time to a certain extent and improve the simulation efficiency.In the simulation of time-domain data,this paper first proposes the back-projection algorithm and its derivative factor fast factorized back projection(FFBP)imaging algorithm used in synthetic aperture,and then analyzes the active detection method.Based on the principle of wall imaging,a novel FFBP imaging algorithm applied to active IR-UWB through-wall imaging was proposed.Considering the influence of the wall,the method of using the law of refraction compensation is proposed to improve the back projection algorithm,and the imaging results verify the effectiveness of the improved algorithm.In the end,aiming at the shortage of the traditional active radar technology,this paper also proposes a new external radiation source radar system based on the known IR-UWB signal,and establishes a model of passive radar through wall imaging under the multi-target environment.