A method and apparatus for generating a frequency-modulated continuous wave (FMCW) signal. The apparatus may include a first oscillator configured to generate a first oscillation signal, a frequency modulator configured to generate a frequency-modulated oscillation signal from the first oscillation signal based on a sequence of control words, a frequency modulation code generator configured to generate a sequence of frequency modulation codes for generating an FMCW waveform, and a frequency multiplier configured to generate the FMCW signal by up-converting the frequency-modulated oscillation signal. The sequence of control words is generated based on the sequence of frequency modulation codes. The apparatus may include a second oscillator configured to generate a second oscillation signal, and a phase detector configured to detect a phase difference between the first oscillation signal and the second oscillation signal and generate an offset code based on the phase difference. The frequency modulator may be a digital-to-time converter.