Simulation and Experiment Investigation of W-Band Dual-Layer Ridge-Loaded Microstrip Meander Line Traveling-Wave Tube

To improve the output power of W-band suspended dual-layer microstrip meander line (SD-MML) slow wave structure (SWS) traveling-wave tubes (TWTs), this article proposes the suspended double-layer ridged-loaded microstrip meander line (SDR-MML) SWS. The performances of the two TWTs under the optimal working voltage conditions were compared. Compared with the SD-MML SWS, the SDR-MML SWS has a greater coupling impedance and can generate a higher output power. To verify the simulation results, the SDR-MML SWS was fabricated by the photolithography process. The experimental test results show that within the range of 90–100 GHz, the reflection loss$S_{{11}}$of SDR-MML SWS is less than −15 dB, and the transmission loss$S_{{21}}$is about −6.5 to −10 dB. The experimental transmission characteristics show a high degree of consistency with the simulation results.