Design of a Low Voltage and High Power Traveling Wave Tube Based on a Sheet-Beam Rectangular Ring-Bar Slow-Wave Structure

In this article, a sheet-beam type ring bar slow wave structure (RBSWS) capable of working at very low-voltage value is proposed. The structure is designed to work over the frequency range from 14 to 18 GHz with a cathodic voltage of 2.050 kV and a current of 100 mA. Simulation results for two 50-period sections, carried out by CST Studio Suite 2023, show a saturated output power of 30 W, a maximum gain of 0.795 dB/mm, and a radio frequency (RF) electronic efficiency higher than 15 %. The proposed structure is ideal for aerospace applications that usually require compact size, low weight and power consumption, while maintaining very high output power levels. Furthermore, this device is relatively easy to manufacture, making it a more accessible option than other structures that require complex and expensive manufacturing processes. Finally, the mechanical and thermal dissipation problems are kept under control thanks to the large surface contact between the slow wave structure and the dielectric rod realized in Boron Nitride.