A frequency-multiplexed Doppler-plus-FMCW hybrid radar architecture: Theory and simulations

Short-range radars are becoming important RF systems in plenty of wireless-sensing applications, such as those in industrial, transportation, security, health, and commercial scenarios. Doppler sensors are very sensitive to vibrations, whereas frequency-modulated continuous-wave (FMCW) radars enable absolute-range discrimination. This article proposes a compact low-cost radar architecture that multiplexes in frequency both operation modes. Furthermore, a theoretical analysis which emphasizes the spectral features of the received baseband signal is included. Simulation results for a K-band hybrid radar example are also provided to validate the expounded mathematical framework.