A 25-W 5-GHz GaAs FET Amplifier for a Microwave Landing System

A 25-W 29-dB gain 5-GHz GaAs FET amplifier has been developed which can be used for a transmitter in the Microwave Landing System. By using 10-W class practical internally matched GaAs FET's hermetically sealed in ceramic packages, the four-stage amplifier has been constructed simply. The amplifier provides 30-W power output with 18.5 percent power efficiency at 17-dBm power input level. It also exhibited an exceffent AM/PM conversion of approximately 1°/dB, compared to 6°/dB for TWT amplifiers.