Complex Permittivity and Permeability Measurements and Finite-Difference Time-Domain Simulation of Ferrite Materials


A methodology to efficiently design products based on magneto-dielectric (ferrite) materials with desirable frequency responses that satisfy electromagnetic compatibility and signal integrity requirements over RF and microwave bands is presented here. This methodology is based on an analytical model of a composite magneto-dielectric material with both frequency-dispersive permittivity and permeability. A procedure for extracting complex permittivity and permeability of materials from experimental data is based on transmission line measurements. The genetic algorithm is applied for approximating both permittivity and permeability of materials by series of Debye frequency dependencies, so that they are represented as double-Debye materials (DDM). The DDM is incorporated in the finite-difference time-domain numerical codes by the auxiliary differential equation approach.


Electrical and Computer Engineering

Research Center/Lab(s)

Electromagnetic Compatibility (EMC) Laboratory

Keywords and Phrases

Analytical Model; Auxiliary Differential Equations; Complex Permeability; Complex Permittivity; Cylindrical Cores; Debye Frequencies; Design Products; Experimental Data; Ferrite Materials; Finite Difference Time Domain Simulations; Finite Difference Time Domains; Finite-Difference Time-Domain Modeling; Microwave Bands; Numerical Code; Signal Integrity; Transmission-Line Measurements; Differential Equations; Differentiation (Calculus); Electromagnetic Compatibility; Ferrite; Finite Difference Time Domain Method; Frequency Response; Genetic Algorithms; Magnetos; Mathematical Models; Permittivity; Superconducting Materials; Dielectric Materials; Cylindrical Core; Debye Frequency Dependence; Finite-Difference Time-Domain (FDTD) Modeling; Genetic Algorithm (GA)

International Standard Serial Number (ISSN)

0018-9375; 1558-187X

Document Type

Article - Journal

Document Version


File Type





© 2010 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Nov 2010