Study on High Frequency Characteristics of Terahertz Ridged Sine Waveguide

In this paper, a ridged sine waveguide structure is proposed, which combines the smooth and continuous characteristics of the sine waveguide with the electric field concentration advantage of the ridged waveguide, intending to achieve a broader operating bandwidth and higher operating frequency in the terahertz frequency band. To verify the design scheme, the waveguide structure is simulated and analyzed using the high frequency simulation software CST, focusing on the effects of each structural parameter of the waveguide on the dispersion characteristics and coupling impedance. The simulation results show that the fundamental mode operating bandwidth of the designed waveguide reaches 87 GHz. The period length has the most significant effect on the dispersion characteristics, while the narrow-side has almost no impact on the dispersion characteristics; moreover, in the backward wave region, the variation of h has a more significant effect on the coupling impedance in the high frequency band. This study provides a novel design scheme for vacuum electronics-based terahertz wave sources, which has specific theoretical and engineering application value.