In the embodiment of FIG. 8C, transmit and receive circuitry 112c includes frequency multiplier circuitry 836, amplifiers 854, and 834, 835, 838, and 842, frequency mixer 840, and frequency dividers 856, 857, and 858. Relative to the transmit and receive circuitry 112b of FIG. 8B, transmit and receive circuitry 112c does not include frequency multiplier 832 because the waveform generator 110c generates microwave RF signals having a center frequency of 60 GHz (unlike waveform generator 110b that generates microwave RF signals having a center frequency of 7.5 GHz, which needs to be increased by a factor of eight prior to transmission by transmit antenna 14 that is configured to transmit RF signals having a center frequency of 60 GHz). RF signals having a center frequency of 60 GHz and amplified by amplifier 834 not only are provided to amplifier 835 and, subsequently transmit antenna 114, but also to a series of frequency dividers 856, 857, and 858 to provide RF signals having a center frequency of 7.5 GHz, which are provided via line 852 to chirp PLL circuitry 826 thereby providing a feedback loop. Whereas line 829 provided the feedback loop for the chirp PLL in the embodiment of FIG. 8B, the feedback loop in the embodiment of FIG. 8C includes line 851, amplifiers 854 and 834, frequency dividers 856-858 and line 852.
