Method for detecting a distance, a radar system and a computer program product

A radar system, comprising:

• a transmitter, comprising a signal generator and antenna, the transmitter configured to transmit a frequency modulated continuous wave (FMCW) radar signal;
• a receiver configured to receive a reflected FMCW radar signal corresponding to the transmitted FMCW radar signal that has been reflected by a reflecting surface;
• and
• a processing unit, comprising a mixer and processor, the processing unit configured to:
• obtain, using the mixer, a beat signal having a frequency corresponding to a frequency difference between the transmitted FMCW radar signal and the reflected FMCW radar signal;
• determine harmonics of the beat signal by Fourier decomposition;
• and
• determine, using the processor, a distance between the radar system and the reflecting surface using phase shift information of at least one of the harmonics, wherein determining the distance comprises determining a phase difference between a pair of the harmonics.

A non-transitory computer readable storage medium having computer-executable instructions stored therein that, when executed by a processor of a processing unit of a radar system that comprises a signal generator, antenna, and mixer, cause the processing unit to:

• obtain, from the mixer, a beat signal having a frequency that corresponds to a frequency difference between a frequency modulated continuous wave (FMCW) radar signal, transmitted using the signal generator and antenna of the radar system, and a reflected FMCW radar signal corresponding to the transmitted FMCW radar signal that has been reflected by a reflecting surface;
• determine harmonics of the beat signal by Fourier decomposition;
• and
• determine a distance between the radar system and the reflecting surface using phase shift information of at least one of the harmonics, wherein determining the distance comprises determining a phase difference between a pair of the harmonics;
• and
• output the distance between the radar system and the reflecting surface.