An EBS L-band amplifier

An Electron Bombarded Semiconductor (EBS) amplifier has been developed which has a combination of characteristics which make it an attractive alternative to metal-ceramic triodes and transistors for generation of high peak powers at lower microwave frequencies. These characteristics include small size, high gain, high reliability and high peak output power. This EBS amplifier has operated at up to 700 W peak output power at 1 GHz with a maximum gain of 27 dB, a bandwidth of 40 MHz, and a target efficiency of 35%. The EBS uses a 10-12 kV electron beam to illuminate a reverse-biased semiconductor diode, producing current gain in excess of 1000 by impact ionization of the silicon. Output matching is performed by a quarter-wave cavity mounted externally to the tube, making it possible to interchange cavities for operation at up to 1.5 GHz. Modifications to the existing design are expected to result in peak output powers in excess of 1-2 kW peak at 1 GHz.