G波段改进型折叠波导慢波结构S参数特性研究OA

For the G-band Modified Folded Waveguide(MFW)Slow-Wave Structure(SWS),two theoretical models are employed to calculate its equivalent conductivity,and the corresponding loss characteristics are analyzed.The effects of machining errors and welding process errors on the S-parameters of the G-band MFW SWS are systematically investigated,including the depth difference of the folded waveguide slots,sidewall verticality,misalignment between the two half SWSs during welding,and electron beam offset.The results show that:for every 1 μm increase in the folded waveguide slot depth,the cutoff frequency decreases by approximately 0.24 GHz;increased sidewall verticality degrades circuit matching and transmission performance,with the cutoff frequency increasing by approximately 4.1 GHz for every 1° increase in sidewall verticality;welding misalignment has an insignificant effect;and electron beam channel offset introduces a distinct stopband at the 3π phase shift,with the Full Width at Half Maximum(FWHM)of the spike increasing by 0.34 GHz for every 1 μm increase in the offset δ.A G-band MFW SWS prototype is fabricated and tested,and its S-parameter characteristics are obtained by comparison with simulation results.The two theoretical models for equivalent conductivity are compared through loss characteristics and attenuation coefficients,and the results indicate that the Hammerstad model is more suitable for calculating equivalent conductivity in the G-band.