Investigation of compact broadband quasi-planar rectangular ring cavity power-combining amplifier

Abstract

ABSTRACTA compact broadband quasi-planar rectangular ring cavity (RRC) power-combining amplifier is presented. To realize the broadband impedance matching, high assembly precision, and the strong coupling between the RRC and the output ports, the novel inserted ground waveguide probe structure was proposed. The measured insertion loss of the passive power combiner is increased from 0.6 to 1.7 dB at the bandwidth 6.5–14.2 GHz. The measured small-signal gain of the four-device power-combining amplifier is 22.2–26.7 dB over a broadband from 8 to 14 GHz. The measured maximum output power at 1-dB compression is 37.7 dBm at 11.4 GHz, with a power-combining efficiency of about 89%. The measured results of the passive power combiner agree with the simulated ones closely.