缺陷态同轴布拉格波导传输特性

采用基于Ansoft HFSS的电磁仿真平台,研究了一个工作于Ka波段（37.5 GHz附近）的缺陷态同轴布拉格波导在不同的开槽方式及缺陷位置条件下的传输特性。结果表明:该波导只有在内外导体壁单面开槽并引入缺陷,或者双面开槽且两个开槽面同时引入缺陷的条件下才能够有效地产生出传输通带;对于后者而言，将内外导体壁的波纹初始相位差设置为且让缺陷位于波导中间时,可以获得带宽极窄、阻带抑制范围较宽的传输通带,此时，给内外导体壁的缺陷引入适度的错位能够对通带的中心频率、带宽等性能指标起到微调作用，而引入大间距的错位则能够在禁带中产生出多个通带，从而起到多通道滤波的作用。

Transmission characteristics of defected coaxial Bragg waveguide

By making use of an electromagnetic simulation tool Ansoft HFSS, transmission characteristics of an example defected coaxial Bragg waveguide operating at Ka band (centred in 37.5 GHz) have been numerically studied. Results show that, if one conductor or both of outer and inner conductors are corrugated with periodical ripples, one or more passbands can be effectively generated by introducing a phase-shift defect to each corrugated surface; for the latter case, if the initial phase difference between the outer-wall ripple and inner-rod ripple is set to and the defects are both in the middle of the waveguide, a passband with extremely narrow bandwidth and wide stop-band rejection frequency range can be achieved; a slight misalignment of the defects between the outer-wall and inner-rod defects can be used to perform a fine adjustment on the character of the passband; however, if these defects are separated with a larger gap, several passbands can be generated, which makes the structure be acted as a multichannel filter. These numerical results are expected to provide engineering references for different applications of defected coaxial Bragg waveguides.