关键词: L波段差分干涉SAR, 陆探一号, 在轨测试, 平面精度, 高程精度, 形变精度

Abstract:

After one year in-orbit test of the China's first L-Band differential interferometric SAR (L-SAR) satellite, which is also named as LuTan-1, we finally conclude that the satellite has reached the pre-defined accuracies. In this paper, we analyzed the key technologies that related to the parameters of the quantitative applications. Three kinds of parameters belonging the long-time geolocation capacity, the digital surface model (DSM) accuracy, as well as the deformation products accuracy are introduced. Results show that the geolocation error of L-SAR is within 3.9 m. We obtained the DSM calibration and validation data in Henan and Jiangsu Provinces. DSM accuracies before interferometric calibration, after calibration and after least square estimation are 13.2, 6.3 and 2.9 m, respectively. We have defined three kinds of deformation products, i. e., deformation products generated using differential InSAR, stacking and multi-temporal InSAR. Accuracies of the three deformation products obtained in Datong of Shanxi Province are 2.7 mm, 8.6 mm/a and 3.7 mm, respectively. Meanwhile, 90% of the strict regression orbit radius was tested to be smaller than 323 m. The components of the decoherence sources were discussed. Final coherence before filtering is better than 0.7 when ignoring the temporal decoherence. The in-orbit test result is encouraging and the satellite will be widely used after its delivery from satellite producers to the users.

Key words: L-SAR, LuTan-1, in-orbit test, geometric accuracy, digital surface model accuracy, deformation accuracy