Provided are a system and method for processing a radar signal for deriving a Doppler frequency from a sampled digital input signal radiated by a frequency modulation continuous wave (FMCW) radar. The system includes a transmission module that repeatedly transmits a radar signal having a unique frequency variation and a pulse repetition interval, a variation module that varies the frequency variation or pulse repetition interval of the radar signal transmitted by the transmission module, an extraction module that, upon occurrence of interference between the radar signal having the varied frequency variation or pulse repetition interval and another radar signal, extracts an interference signal from the varied radar signal, and an adjustment module that adjusts the radar signal to reduce the extracted interference signal.