Experimental violation of the Start-Stop-Approximation using a Holistic Rail-based UWB FMCW-SAR System

This paper presents a rail-based near-field FMCW-SAR system, used for generating data with up to 25.6 GHz bandwidth at velocities up to 4 m/s. System parameters like squint or depression angel are freely adjustable. Image processing is implemented on an FPGA-based hardware in real-time with the backprojection algorithm. Results are optically projected onto the scene for verification. As a practical example, the consequence of a start-stop-approximation violation with varying velocity and ramp-length is shown. Additionally, the correction of this violation is investigated.