UHF-Band Long-Pulse Radar Power Amplifiers using Push-Pull and Balanced Configurations

UHF-band long-pulse radar BJT power amplifiers using push-pull and balanced configurations are presented. The NPN BJTs are fabricated in a state-of-the-art 6" silicon wafer fab at Integra Technologies Inc. The BJTs are internally matched and mounted on BeO package. To handle low frequency oscillations, band-rejection filter type bias circuit and negative feedback are employed. Common base configuration and class C bias are used. The device DC parameters are BVces = 86 V and Hfe = 25. Operating with PW=1.1ms and DF=26%, the power amplifiers provide more than 500-W output peak power, 50-% efficiency, and 8.2-dB gain from 400 MHz to 460 MHz.