Dual Gunn device oscillator with 10mW at 280 GHz

The performance of an in-line WR-6 waveguide power combiner was evaluated with three second-harmonic InP Gunn devices around 280 GHz. The spacing between the two waveguide cavities was varied using WR-6 waveguide spacers. In one configuration, an output power of 10.5 mW was measured at a second-harmonic frequency of 280.7 GHz. This output power corresponds to an overall DC-to-RF conversion efficiency of 0.33% and a power-combining efficiency of more than 110%.