Development of 1.2 kW C band solid-state high efficiency GaN microwave source

As the efficiencies of the traditional high power solid state Si microwave source and GaAs microwave source are low and their performances are poor at high temperature, we have developed a 1.2 kW C-band all solid state high efficiency GaN microwave source by using the low loss coaxial waveguide spatial power combining technique which utilizes GaN units power amplifier module integration. The experimental result shows that the efficiency of the GaN microwave source is high and it can safely and reliably operate at high temperature. A single C-band GaN power amplifier module unit integrates a 6-bit phase shifter with a phase shift precision of 5.6, a gain of 35 dB, and an output power greater than 31 W. The continuous output power of the microwave source is 1.2 kW, the total efficiency is 30%, the harmonic suppression is -54.8 dBc, the stray is -63.69 dBc and the phase noise is -94.03 dBc/Hz@1kHz.