Equivalent Circuit Analysis of Spiral-Type Transmission Line with Mn-Zn Ferrite Core

Abstract

We developed spiral-type transmission line device consisting of a spiral winding with a polyimide dielectric film, a ground plane, and a Mn-Zn ferrite pot core. To analyze the transmission characteristics of the devices, we introduced a coupled distributed constant circuit model. Differential equations for voltage and current obtained from the analysis model include impedance and admittance matrixes representing electromagnetic coupling between different turns. As a result, the calculated transmission characteristics agreed well with the measured ones.