I. Introduction
Frequency-modulated continuous-wave (FMCW) radar has been widely used in autonomous driving [1] and short-range surveillance [2] due to its precise motion measurement and low cost for feasible mass deployment [3]. However, as most automotive FMCW radars operate in highly overlapping frequency bands [4], self-radar may experience interference from other automotive radars, which is a significant and unavoidable problem. One method to alleviate this issue is to design interference-aware cognitive radar [48], which estimates the signal parameters of other automotive radars and dexterously selects unoccupied frequency bands. On the other hand, to counter short-range surveillance devices, the electronic countermeasures (ECM) system must identify the modulation mode and estimate the parameters of the intercepted signal to develop an optimal jamming attack [5]. Consequently, the recognition and estimation of FMCW signals are of great importance.