Tuning characteristics of 94 GHz waveguide VCO

We have proposed a new tuning method of 94 GHz waveguide voltage controlled oscillator (VCO). We have designed and fabricated a varactor-tuned 94 GHz second harmonic VCO. We discuss a new method that a simple and effective tuning method increases greatly the bandwidth of the VCO with high output power and operating frequency simultaneously for the FMCW radar system by applying a controlled impact to the Gunn diode. The VCO employs a commercially available GaAs Gunn diode in packaged form and a GaAs Gunn diode mounted in a waveguide cavity. Also, we adapted MINT's GaAs Gunn diode.