Interaction efficiency of an emission gated TWT

Abstract

The Emission Gated Device Experiment extracts RF power from a prebunched electron beam passing through a short helix traveling wave circuit. Efficient and compact amplifiers are possible through this approach because of the large component of RF current in a tightly bunched beam. While a wideband, high gain, high power input circuit for such devices is beyond the present state of the art, high transconductance gated field emission cathodes are being developed for emission gated devices. The present experiment is designed to test the performance of the output coupler using a cavity-driven cathode circuit. Twenty percent beam coupling efficiency has been observed from a helix one slow wavelength long.<>