A Compact Microstrip High-Power High-Efficiency Avalanche-Diode Oscillator (Correspondence)

This paper describes a simple compact L-band microstrip oscillator circuit using avalanche diodes operating in the high-efficiency mode. The circuit has produced 150 watts with 26-percent efficiency; the duty cycle is 1 percent at the 100-watt power level. The overall size of the circuit is reducible to 1 by 2 inches using metal-on-alumina microstrip. Frequency tuning between 1.62 GHz and 1.83 GHz with less than 1.2-dB variation in power output has been demonstrated.