94 GHz Waveguide VCO for FMCW radar

In this paper, we designed and fabricated waveguide voltage controlled oscillator (VCO), which have a center frequency of 94 GHz using the GaAs Gunn diode, varactor diode, and two bias posts with low pass filter (LPF). The cavity is designed for fundamental mode at 47 GHz and operated second harmonic VCO of 94 GHz center frequency. The fabricated VCO has 1.74 GHz bandwidth, 671 MHz linearity for 2.28% and 14 dBm output power. The highest output power is 15.58 dBm at 94.38 GHz.