Sampling quantization analysis and results for FMCW SAR

One of the advantages of Frequency Modulated Continuous Wave (FMCW) radars is the relative low required sampling frequency even when transmitting high bandwidths. This is a consequence of the inherent homodyne configuration of the radar front-end. A simple way to reduce further the data rate is to use few bits per sample. The paper analyzes the effects of low bit sampling in FMCW Synthetic Aperture Radar (SAR) data. A low number of bits used to sample the FMCW deramped signal could produces spurious peaks and intermodulation products of the sinusoidal signal. However, it is shown in the paper that, for typical value of signal to noise ratio in FMCW systems, white noise suppresses the spurious products. Simulation results and verifications on real data collected with the FMCW SAR system built at the Delft University of Technology are presented.