矩形栅慢波系统的高频特性分析

 对于矩形栅这一经典的慢波结构，采用场匹配法来分析其慢波特性，进而得到其耦合阻抗。其中对槽区内的场处理，保留其高次项，表示为一无限本征驻波之和的形式。然后通过数值实例具体分析了矩形栅的两种典型结构：浅槽栅和深槽栅。当增大槽深后，色散增强，系统通带变窄，同时耦合阻抗有明显增大，工作点移向前向波区，适合用在放大器的慢波结构上。

High frequency characteristics of rectangular waveguide grating

In order to analyze the rectangular waveguide grating which is a typical slow wave structure, the dispersion relation was obtained by the field-matching method. The coupling impedance was subsequently obtained from the relevant equations. The higher orders were retained as an infinite sum of standing eigen-waves to deal with the fields inside the grooves. Computations and analysis were done for two typical structures of the rectangular waveguide grating, the shallow grating and the deep grating, and reasonable results were obtained. The results show that the deeper the groove is, the stronger the dispersion is and the narrower the pass-band is. The coupling impedance increases significantly. The operating point moves toward the forward wave zone, it is fit for the slow wave structure of an amplifier.