Efficient SAR raw data generation including low squint angles and platform instabilities

The performance of high-resolution synthetic aperture radar (SAR) systems under degrading conditions such as uncontrolled platform motion can only be analyzed and evaluated by modeling the whole imaging system through simulation. A major scientific problem, however, is the generation of spotlight mode SAR raw data because of the need for high numerical and modeling accuracy, and restricted computer time and space. Taking into account a squinted geometry and platform instabilities, the common generation of raw data in the time domain becomes time inefficient. This letter proposes a raw data generator with which the spotlight mode raw data set of an extended scene can be simulated and which combines the precision obtainable when working in the time domain with the efficiency of work in the frequency domain. The generated raw data are processed and analyzed to quantify the quality of the proposed simulation tool.