Design of a Planar Helix Slow Wave Structure for TWT applications in the K-Band

A novel slow wave structure (SWS) consisting in a planar helix with straight-edge connections, operating in the K-band with a very low cathodic voltage, is herein proposed. The structure has been designed so to have a working band centered around 20 GHz. Considering an electron beam generated by a cathode with voltage and current of 1700V and 15mA respectively, we have predicted a gain of 35dB and a saturated output power of 5.5W at 20GHz in a 100 periods structure. Furthermore, our SWS has been designed in order to be more promising in terms of fabrication, if compared with other similar structures already reported in the literature.