Performance Analysis And Application Of UAV Interferometric SAR System

Unmanned aerial vehicle(UAV)combined with repeat-track interferometry technology can not only obtain high spatial resolution and high density crustal deformation field,but also effectively avoid a series of technical problems such as time decorrelation,so as to realize and finally meet the requirement of near real-time monitoring of various geological and seismic disasters.However,small UAVSAR is vulnerable to the disturbance of flight speed,direction,attitude and airflow due to its small and light platform.At the same time,limited by the load,power and size of the platform,it is not suitable to be equipped with high-precision integrated inertial navigation system.It is difficult to guarantee the ability of high resolution imaging and high precision attitude control.Focusing on the National Natural Science Foundation of China's "key technology of UAV differential interferometric SAR Monitoring Crustal Deformation",the author of this paper mainly studies the imaging parameters and system performance,route design criteria,image positioning accuracy and application ability of UAV differential interferometric SAR system on the basis of participating in the preliminary investigation and hardware assembly of UAV differential interferometric SAR hardware system.The main achievements include:(1)Performance analysis of UAV interferometric SAR systemOn the basis of summarizing the construction and algorithm research status of airborne heavy rail interferometry system at home and abroad,and the UAVSAR system developed by the project team,this paper analyzes the UAV system performance,such as system load,endurance time,working height,etc.,and analyzes the SAR system strip width,resolution,sampling interval and other imaging related parameters.(2)SAR route design and geometric calibration experiment of small UAVIn this paper,the route design scheme of uavsar is studied,which is suitable for complex operation environment such as active fault zone.Based on the above criteria,flight test and field calibration test are designed in Beichuan County,Sichuan Province.Based on the analysis of the measured track data,the baseline and motion error limits under the interference conditions are studied.At the same time,in order to meet the needs of practical application,the positioning accuracy of uavsar image suitable for disaster emergency,high-precision topographic mapping and other conditions is analyzed.(3)UAV SAR data processing and image quality evaluationBased on the characteristics of the radar data,the corresponding data interface is developed,and the whole set of data processing flow of UAVSAR integrated system is studied.Finally,based on the requirements of business application,the amount of image information,the classification effect of ground objects,the interference accuracy and the performance of stereo pairs are analyzed,which provides guidance for the subsequent application.