A Study Of Data Processing Technology Of High-resolution InSAR Systems On Disturbed Platforms

Interferometric Synthetic Aperture Radar is an important means to obtain the three dimensional information of a large area of terrain quickly and accurately. With the growing need for fast-response applications and to confirm the system’s design and algorithm for large projects on satellite platform, the In SAR systems on disturbed platforms, such as airplanes and automobiles, have received more and more attention in the research and development. The In SAR systems on platforms of this kind have the advantages of fast response, high maneuverability and low cost, while the unstable movement of the platforms in the process of data recording makes the In SAR data processing more difficult. Combined with the high-resolution developing trend of In SAR technology, this dissertation is focused on the study of data processing technology of In SAR systems on disturbed platforms and the application of parallel computing technology in In SAR data processing. The main work of this dissertation is as follows:1. The algorithm of In SAR imaging processing and motion compensation of In SAR systems on disturbed platforms is studied. Based on the processing experience of large scales of real data, the ways to acquire the real trajectory and the normal trace from the POS data are introduced in detail, as well as how to compute the referable track and velocity for In SAR interferometric processing. In addition, a general flow of imaging processing for high-resolution In SAR systems on disturbed platforms is proposed.2. On the basis of processing and analyzing a large scale of real automobile SAR/In SAR data, the problems of data processing of automobile In SAR are summarized and the data acquiring geometry of the automobile In SAR system is analyzed when observing the mountains. Then a detailed description of the way to compute the automobile SAR/In SAR motion compensation parameters based on the knowledge of coarse terrain is proposed, and the real data processing results confirm the validation of the method for computing the range difference and the In SAR imaging processing flow.3. The method for obtaining the range difference in motion compensation and imaging processing is studied for single-pass In SAR systems on airplane, especially for the systems of standard interferometric mode. According to the method and the In SAR imaging flow given before, the real airplane In SAR data is processed. The images are well-focused and the baseline can be compensated to a stable vector. The clear interferograms indicate that the single-look-complex SAR images obtained from the given In SAR imaging processing flow can be used in the following interferometric processing.4. After studying the key processing steps of SAR interferometry, the new problems of interferometric processing for high-resolution In SAR systems on disturbed platforms are analyzed, and then a flow of interferometric processing for high-resolution In SAR systems on disturbed platforms is presented. Particularly, a method for In SAR target locating based on recursion formulae is proposed to deal with the high-time-cost problem of traditional In SAR locating method. Finally, the real data of In SAR systems on automobile and airplane is processed to confirm the reliability of the proposed processing flow and the method in engineering applications.5. To deal with the problem of rapidly growing scale of In SAR data and more processing time cost resulting from the factors such as improving resolution, the method for speeding In SAR data processing is studied. The multi-thread processing on multi-core CPU using Open MP and the parallel processing on systems consist of CPU and GPU are implemented respectively, both of which can achieve well speed-up ratios in the In SAR imaging process. This research is valuable to engineering applications.