Multi-target Monitoring for Distinguishable Range Improvement Using a Hybrid FMCW-FSK 24 GHz Radar

This paper presents an approach to improve the distinguishable range by using a hybrid frequency modulated continuous wave (FMCW) - frequency shift keying (FSK) of 24 GHz Radar. For traditional FMCW radar, the range resolution is inversely proportional to the bandwidth of radar. The proposed hybrid FMCW-FSK radar utilizes an overlapped chirp waveform. The distance corresponded to every frequency can be detected if the targets in the same range bin has different Doppler frequencies. Therefore, the fundamental theoretical limit of range resolution can be broken through applying the proposed waveform. From the experimental results, the distinguishable range is 27.2 cm for 150 MHz bandwidth, compared to traditional 1m resolution. Accordingly, the ratio of improvement is 3.6 times.