Meander-Line Slow-Wave Structure for High-Power Millimeter-Band Traveling-Wave Tubes with Multiple Sheet Electron Beam

For advanced telecommunications and radar systems, high-power miniaturized millimeter-band traveling-wave tubes (TWTs) are required. In this letter, we propose a meander-line slow-wave structure (SWS) that is suitable for multiple sheet beam interaction that helps achieve high power. The simulation of cold electromagnetic parameters of the V-band SWS demonstrates good transmission characteristics, wide bandwidth, and high interaction impedance. Hot performance of the V-band TWT amplifier with the proposed SWS is also studied. The 3-D particle-in-cell (PIC) simulation predicts that the designed circuit yields a stable gain in the 50 – 70 GHz frequency range with a 25 – 30-dB small-signal gain. 250-W average output power is attained from a 1.5 – 2.0-W input driving signal at 68.1 GHz.