毫米波脊加载开放式矩形栅慢波系统的研究

Novel Slow-Wave Structure with Ridged Open Rectangular Grating for MM-Wave Traveling Wave Tube

提出了一种新型慢波结构—脊加载开放式矩形栅慢波系统。作为一种全金属慢波结构,脊加载开放式矩形栅适用于高功率宽频带的行波管的互作用慢波结构。利用脊相邻面的阶跃条件以及互作用区和加载区的场匹配条件和单模近似法,推导了该结构的色散方程和耦合阻抗表达式。同时,采用软件模拟验证理论分析的正确性,并分析了结构参数对慢波结构慢波特性的影响。数值计算结果表明:在槽深一定的情况下,加载脊可以非常显著地改善该结构的慢波特性,通过优化开放式矩形栅的脊的宽度和厚度等参数来兼顾色散和输出功率等不同设计要求。本文的脊加载开放式矩形栅慢波结构理论研究可以作为高功率行波管设计的理论基础。

A novel type of the all-metalslowwave structure（ SWS）,with a ridged openrectangular grating,was successfully developed for the high-power,high-frequency,wide-band millimeter wave traveling wave tube（ TWT）.The influence of the SWS geometry on the SWS characteristics,including its dispersion equation and coupling impedance,was empirically approximated,mathematically modeled withthe jumping conditions at the interface of the two neighboring ridges,theoretically calculated in field matching theory,and numerically simulated with 3-D software package HFSS. The simulated results show that the optimized ridges at a fixed grating depth significantly improve the SWS dispersion characteristics and coupling impedance. The simulated and calculated results were found to be in good agreement. In addition,the thickness and gap-width of the ridges of the newly-developed SWS structure can be optimized to meet the specific requirements on the output and dispersion.