Effects of Systematic FMCW Radar Sweep Nonlinearity on Bias and Variance of Target Range Estimation

In linear frequency modulated continuous wave (FMCW) radar systems, the quality of target range estimation is directly associated to the linearity of the transmitted frequency sweep. In this paper we introduce a novel technique for analyzing the effects of systematic sweep nonlinearities on bias and variance of target range estimates, applicable to the commonly used Fourier transform based evaluation methods. A prototype FMCW radar system, capable of generating nonlinear frequency sweeps, is presented and used to verify the theoretical results on real measurement data