High precision DEM generation using airborne dual-antenna InSAR data：A case study of large hilly areas

Abstract

The airborne interferometric synthetic aperture Radar( InSAR) is a new technique for generating digital elevation model( DEM) with high accuracy. To generate high precision DEMs in large areas,this paper introduces accurate parameter calibration and bundle adjustment to the pre existing data processing flow of airborne InSAR DEMs generation,and presents a novel method and procedure for massive high precision DEMs generation by using airborne dual- antenna InSAR data of hilly areas, which includes parameter calibration, interferometric processing,bundle adjustment,phase- to- height conversion,geo coding and mosaicking. The airborne InSAR for the topography mapping processing system has been exploited based on the VC + +. Some experimental research is presented based on airborne dual- antenna X- band InSAR data of 4 stripes. The authors processed and generated a high precision DEM covering an area of over 500 km2. Several corner reflectors were placed in this area as reference GCPs for the assessment of the accuracy of the generated DEM. The evaluation results in terms of the mean square error( MSE) were derived by comparing the generated InSAR DEM with the reference GCPs. The MSE of the point and the height are ± 1. 188 m and ± 0. 508 m,respectively. It is concluded that the generated DEM using the proposed method meets the requirements of 1∶ 10 000 terrain mapping. The airborne InSAR system could provide a new technique for topographic mapping in large complex areas.