薄衬底共面波导的特性分析

Characteristic Analysis for CPW′s on Thin Substrate

本文推导出了薄衬底共面波导特性参数计算的近似解析表达式 ,避免了薄衬底保角变换中的“拥挤现象” .利用该表达式并结合部分电容法可以计算在导体与衬底之间加薄绝缘层的共面波导的特性参数 ,分析结果与实验数据相符合 .

To avoid the “crowding phenomenon” in conformal mapping,approximate analytical expressions of characteristic parameter for CPW′s on a thin substrate have been derived.Combining these expressions with the partial capacitance method,we can calculate the characteristic parameters for CPW′s with a thin insulative film between the conductors and substrate.A practical example is analyzed and agrees well with the test data.Finally the effect of an insulated thin film between the conductors and Si substrate on loss factor of microwave transmission lines is analyzed.