Design of a high power S-band metamaterial backward-wave oscillator

This paper presents the design of a novel backward-wave oscillator (BWO) that uses a negative index mode in a waveguide filled with a metamaterial (MTM). The MTMBWO is designed to operate at 2.6 GHz with electromagnetic simulations using the HFSS code. CST PIC simulations were performed of the device and predict a saturated output power of 5.75 MW using a 500 keV, 80 A electron beam (14% efficiency). In addition, a brass cold test structure of the proposed MTMBWO was built and tested with a vector network analyzer and showed very good agreement with simulation.