Detection Performance Improvement of FMCW Radar Using Frequency Shift

Frequency modulated continuous wave (FMCW) radars have been widely used for measuring target range and speed. In this paper, we present a mathematical model that quantifies the system-level performance of FMCW radar systems. In FMCW radar, the target range is measured through measuring the beat frequency between the transmitted and received signal, usually by using Fast Fourier Transform (FFT). One drawback of this approach is that when the beat frequency of a target is not on the FFT grid, both the detection probability and the false alarm rate (FAR) performances are degraded. In this paper, we propose a new detector, using frequency shifts, that improves the detection probability for off the grid targets at a cost of a slight increase in FAR.