Improvement of intermodulation distortion in microwave power amplifiers with intrinsic second-harmonic short-circuit termination

Intermodulation distortion products and their asymmetry in microwave power amplifiers were drastically improved by intrinsic drain second-harmonic short-circuit termination. The FET drain parasitic inductance was taken into account to construct a series resonant circuit with a resonant-frequency at the second-harmonic. 1 GHz- band Si MOSFET power amplifiers were fabricated and the remarkable improvement of third-order and fifth-order intermodulation distortion products and their asymmetries were achieved by the proposed second-harmonic short-circuit termination.