AN APPROACH TO POSITIONAL QUALITY CONTROL METHODS FOR AIRBORNE INSAR HIGH-RESOLUTION X-BAND ORTHOIMAGES AND P-BAND DIGITAL TERRAIN MODEL

Uma abordagem de métodos de controle de qualidade posicional para modelos digitais de terreno de banda P e ortoimagens de banda X de alta resolução de radar interferométrico (InSAR) aerotransportado

Abstract:

The positional validation of datasets is an important step for cartography studies since it allows learning about its accuracy, and also indicates the data process quality. However, the positional validation of Synthetic Aperture Radar (SAR) datasets have some additional challenges when compared to optical images due to the geometric distortions. We employ existing targets such as traffic signs and lampposts in the scene and identify them on the image as control points. We performed the validation of the geographic coordinates used as planialtimetric positional control points, using both the amplitude backscattering orthoimage and the Digital Terrain Model (DTM) generated from the InSAR system. We employed the NMAS, ASPRS and NSSDA tests along with information by the Brazilian Standards. This validation showed these control points presented the following results for 1:10,000 scale: NMAS test - class “A” in PEC and PEC-PCD; ASPRS test - RMSE _x = 1.317m, RMSE _y = 1.231m and RMSE _z = 1.145m; and NSSDA test - RMSE _r = 1,802m, Precision _r = 3.118m and Precision _z = 2.244m. These results prove we can use the proposed targets as control points and the used InSAR datasets meet the expected quality for generation of geotechnic products for 1:10,000 scale.

Keywords:
SAR Dataset; Positional Validation; Accuracy Test; Brazilian Standardization; NMAS; ASPRS and NSSDA