平面人工传输线等效集总参数经验公式的研究

摘要

平面人工传输线是一款性能良好的新型慢波结构，主要由弯曲线电感、交指电容等微带准集总元件构成。系统研究了弯曲线电感和交指电容的等效集总参数随结构参数变化的规律并给出反映这些规律的经验公式，考虑微带介质基板厚度和介电常数的影响，将所得经验公式进行修正使之适用于不同介质基板厚度和介电常数的情况，将修正的经验公式应用于基于平面人工传输线的威尔金森功分器的设计中。所得经验公式可用来快速、准确地设计平面人工传输线，对其他微带不连续或慢波结构的设计也具有参考意义。%The novel planar artificial transmission line （PATL） is a type of slow- wave structure composed of microstrip quasi-lumped elements like meandered-line inductor and interdigital capacitors. This paper investigates on the relations be- tween the physical parameters and the effective lumped parameters of the mean- dered-line inductor and interdigital capacitor and concludes the corresponding em- pirical formulas. Those formulas are then generalized considering the influences of substrate thickness and substrate permittivity. The modified formulas are then ap- plied to the design procedure of PATL-based Wilkinson power divider. It is expec- ted that the empirical formulas proposed in this paper would improve both design efficiency and design accuracy of the novel planar artificial transmission line, and are also useful in designing other microstrip discontinuous or slow-wave structures.