A 1kW-class S-band compact waveguide combiner unit with GaN HPAs for WPT and space communication

Using a GaN high power amplifier and a double 4-inputport circular waveguide combiner, a 1kW S-band compact waveguide combiner unit operating at 2.1 GHz was assembled. The maximum power of 200W was realized with a Peltier device for heat sink. The high power amplifier unit shows the PAE of more than 50% with an AB-class operation under the temperature around 40 degrees C. The four GaN high power amplifiers were combined with the 4-inputports circular waveguide combiner, having an output power of 540W. Further the 1kW output power connecting two 500W-class power combiners was achieved. The combining efficiency of the 1kW-class power combiner unit was achieved to about 90 %.