Research On DEM Data Processing Method Of INSAR In International Space Station

The International Space Station (ISS) is an outer space base which has the most perfect function in the near-earth space. It represents the leading edge in the domain of spaceflight technology. To exploit and utilize ISS sufficiently is a great project that benefits mankind. The Interferometric Synthetic Aperture Radar (INSAR) is a technology which is most preponderant in obtaining Digital Elevation Modal (DEM). Especially, the spaceborne INSAR, which has the advantage of imaging stabilization and obtaining DEM free from the national boundary restriction, has been attached abroad importance all over the world increasingly. This thesis combines these ideas and the twin antennae of INSAR are carried aboard the International Space Station as the external earth-observation equipments. This configuration overcomes the disadvantages of existing spaceborne INSAR systems, such as the low coherence of obtaining data, the complexity of data processing. It can gain high precision DEM through simple manipulations.The ultimate intention of this thesis is the feasibility argumentation of across-track INSAR twin antennae carried aboard the International Space Station to obtain DEM. Firstly, the fundamental of INSAR and Differential Interferometric Synthetic Aperture Radar (DINSAR) are expatiated. The interferometric phase and differential phase are decomposed into several segments which are analyzed one by one. And two preconditions of carrying out INSAR are summarized according to the correlations in time and space. Secondly, the configuration and parameters of the INSAR system carried aboard the International Space Station are analyzed. And the predominance of ISS as the platform of INSAR is summarized. Thirdly, the means of emulating interferometric phase data directly is brought forward, which reduces the operation quantity and improves the emulation rapidity. Fourthly, the realization processes of INSAR and DINS AR are expounded. The results of different realizing methods of phase filtering and unwrapping are compared. Finally, based on the analyzed system parameters and the existing DEM, interferometric phase and the entire procedure of processing interferometric data to obtain DEM are emulated. It is validated that this system can also be used in differential process to detect the deformation of earth surface.The parameter analysis and emulational results prove that the system of the twin antennae of INSAR carried aboard the International Space Station is feasible.