Range resolution improvement for FMCW radars

Abstract

Frequency modulated continuous wave (FMCW) radars have been widely used in many on-chip system applications. Compared to the traditional pulse radars, the most attractive features of FMCW radars are power saving and low peak-to-average power ratio. However, due to the sampling rate constrain of the FMCW radar, there is a bottle-neck on the target range resolution if peak detection on the spectrum is used. This paper analyzes the spectrum of the received signal and proposes a curve-fitting based method that improves the range resolution of FMCW radars. With the proposed method, the range resolution can be improved by 20 times. For robustness, our algorithm still works even when signal-to-noise-ratio (SNR) is as low as -10 dB.