A five-element 150/300 GHz frequency doubler

A five-element in-line frequency doubler array at 300 GHz in a spatial power dividing/combining circuitry has been investigated. The waveguide doublers are realized with GaAs-Schottky-diodes and operate with 4% efficiency. Preliminary measurements of the system resulted in 8.35 mW output power. After a redesign, an overall efficiency of 2.5% (10 mW @ 300 GHz) is expected.