Power-Combined GaN Amplifier With 2.28-W Output Power at 87 GHz

Future remote sensing instruments will require focal plane spectrometer arrays with higher resolution at high frequencies. One of the major components of spectrometers are the local oscillator (LO) signal sources that are used to drive mixers to down-convert received radio-frequency (RF) signals to intermediate frequencies (IFs) for analysis. By advancing LO technology through increasing output power and efficiency, and reducing component size, these advances will improve performance and simplify architecture of spectrometer array systems. W-band power amplifiers (PAs) are an essential element of current frequency-multiplied submillimeter-wave LO signal sources. Substantial W-band (75–110 GHz) power is required due to the lossy passive frequency multipliers used to generate higher frequency signals in nonlinear Schottky diode based LO sources. By advancing PA technology, the LO system performance can be increased with possible cost reductions compared to current gallium arsenide (GaAs) PA technology.