SAR Imaging Of Vital Signs In A Complex Indoor Environment

The imaging and recognition of human targets has a wide range of needs in post-disaster search and rescue,urban rescue and other aspects.Current imaging of the human body includes optical imaging,infrared imaging,and through-wall imaging.Optical imaging is not suitable for all-weather,all-day,full-area imaging;infrared imaging is susceptible to interference from other heat sources and obstacles;through-wall imaging equipment is expensive and bulky,and is not suitable for human recognition in complex scenes.Imaging.Therefore,designing a two-dimensional imaging system that can cover both the whole region and the human body in a complex environment has very important practical significance for safety and rescue applications.This paper proposes a duplex radar system based on multi-track fusion for vital sign SAR imaging,and is also equipped with a drone to realize human recognition and imaging in complex environments.The system first obtains the two-dimensional SAR image of the whole region through the frequency modulated continuous wave(FMCW)mode,and simultaneously detects the vital signs of the human target through the CW mode,thereby obtaining the human body imaging in the entire region.The main work is as follows:1?The duplex radar system based on drone has been introduced.The principle of the transceiver module and control module of the system were described respectively.The signal analysis of the duplex radar receiving signal was carried out.2?The FMCW SAR imaging algorithm based on time domain processing and frequency domain processing has been introduced respectively,and the advantages and disadvantages of the two algorithms have been compared by simulation.In order to realize the imaging of the whole region,this paper proposed a SAR imaging algorithm based on multi-track fusion.Using the principle of radar trajectory extraction,only the signals moving in the azimuth direction were imaged,and the images were integrated to obtain complete imaging.In addition,by comparing the experiment with the traditional monorail SAR imaging,it could be found that the imaging in the processing of a wide and complex scene was more advantageous,and finally the reliability of the algorithm was verified.3?The principle of human body recognition based on CW mode has been introduced.Then,a vital SAR imaging system based on duplex radar was proposed.The SAR imaging algorithm based on multi-track fusion was used to image the whole region and the human body recognition algorithm was used to identify the human body.The goal was to achieve human imaging in a complex environment,and the effectiveness of the algorithm was verified by actual experiments.4?The experimental platform of the duplex radar system equipped with drones was established,and the experimental scheme was designed.The monorail and multi-track UAV experiments were carried out respectively.The experimental results show that the minimum error of human target positioning is 0.06 in the indoor area of 4 m×9 m.m,experimental results verify the effectiveness of the system.