Moving target identification without special radar mode

摘要

This disclosure is directed to techniques for an FMCW radar system to determine an unambiguous radial velocity of a target. The radar system measures the Doppler shift in the received return signal reflected from the target, while the radar system simultaneously performs normal surveillance functions. Such a radar system may digitize the beat frequency that results from mixing the received return signal from a target the transmitted signal for a given frequency ramp. The radar system may divide the usable digitized samples at the output of an analog-to-digital converter (ADC) into a number of subsets and analyze the frequencies in each subset. Because each subset of samples covers a time interval that may be substantially less than the period of each frequency ramp, the radar system may extract without ambiguity the Doppler velocity of a target within as little as the period of single frequency ramp.