Time domain SAR raw data simulation using CST and image focusing of 3D objects

This paper presents the use of a general purpose electromagnetic simulator, CST, to simulate realistic synthetic aperture radar (SAR) raw data of three-dimensional objects. Raw data is later focused in MATLAB using range-doppler algorithm. Within CST Microwave Studio a replica of TerraSAR-X chirp signal is incident upon a modeled Corner Reflector (CR) whose design and material properties are identical to that of the real one. Defining mesh and other appropriate settings reflected wave is measured at several distant points within a line parallel to the viewing direction. This is analogous to an array antenna and is synthesized to create a long aperture for SAR processing. The time domain solver in CST is based on the solution of differential form of Maxwells equations. Exported data from CST is arranged into a 2-d matrix of axis range and azimuth. Hilbert transform is applied to convert the real signal to complex data with phase information. Range compression, range cell migration correction (RCMC), and azimuth compression are applied in time domain to obtain the final SAR image. This simulation can provide valuable information to clarify which real world objects cause images suitable for high accuracy identification in the SAR images.

[1]  Karsten Schulz,et al.  Coherent simulation of SAR images , 2009, Remote Sensing.

[2]  Lorenzo Bruzzone,et al.  Radar Imaging Simulation for Urban Structures , 2011, IEEE Geoscience and Remote Sensing Letters.

[3]  Giorgio Franceschetti,et al.  The SAR simulation: an overview , 1995, 1995 International Geoscience and Remote Sensing Symposium, IGARSS '95. Quantitative Remote Sensing for Science and Applications.

[4]  Ian G. Cumming,et al.  Digital Processing of Synthetic Aperture Radar Data: Algorithms and Implementation , 2005 .

[5]  Bernard Mulgrew,et al.  Generation of SAR Image for Real-life Objects using General Purpose EM Simulators , 2009 .

[6]  John Amanatides,et al.  A Fast Voxel Traversal Algorithm for Ray Tracing , 1987, Eurographics.

[7]  Uwe Stilla,et al.  Hybrid GPU-Based Single- and Double-Bounce SAR Simulation , 2009, IEEE Transactions on Geoscience and Remote Sensing.

[8]  Helmut Süß,et al.  An End-to-End-Simulator for Spaceborne SAR-Systems , 2002 .

[9]  Richard Bamler,et al.  Ray-Tracing Simulation Techniques for Understanding High-Resolution SAR Images , 2010, IEEE Transactions on Geoscience and Remote Sensing.

[10]  M. Wohlers,et al.  Computer Simulation of Synthetic Aperture Radar Images of Three-Dimensional Objects , 1980, IEEE Transactions on Aerospace and Electronic Systems.