A Cavity Based High Power Solid State RF/Microwave Amplifier

This paper describes the theory and development of a high-power solid-state amplifier technology for RF and microwave frequencies. The amplifier, which contains a large number of transistors, utilizes a pair of resonant cavities that efficiently function as input distributor and output combiner. Moreover, the modal structure and the high intrinsic Q of the cavities provide the required high transformer ratio for i/o matching and low insertion loss. The physical cavities can serve as heat sink, and also provide dc grounding and RF shielding. Experimental results show, among other desirable features, a 3dB bandwidth of 10% and a combining efficiency in the high 90% range. The structural design lends itself to ease of manufacture.