Parallel-fed c.w. Gunn oscillators cascaded in X band waveguide for higher microwave power

Waveguide devices containing several GaAs Gunn diodes, synchronised to operate at single frequency, have been constructed. Four diodes, cascaded in a waveguide and biased at the same voltage, delivered 300 mW at 9 GHz. These parallel-fed arrays of Gunn oscillators can be tuned to be highly directional. Directivity of 20 dB was observed.