Hybrid FMCW-interferometry radar system in the 5.8 GHz ISM band for indoor precise position and motion detection

A hybrid FMCW-interferometry radar sensor is presented. The proposed measurement system incorporates the linear frequency-modulated continuous-wave (FMCW) mode and the continuous wave (CW) interferometry mode. The radar system works in 5.8 GHz ISM band with a bandwidth of 160 MHz. Equipped with a special signal processing method, the hybrid system is capable of detecting absolute distance as well as slow motion. Experiments show that the absolute position detection has an average accuracy of 1.65 cm, and the accuracy of relative motion tracking is better than 2 mm.