Analysis of Conduction Noise Attenuation by Magnetic Composite Sheets on a Microstrip Line by the Finite Element Method

Metals and Materials International (Impact Factor: 1.58). 02/2010; 16(1):115-119. DOI: 10.1007/s12540-010-0115-7


Conduction noise attenuation by magnetic composite sheets along a microstrip line has been analyzed by using an electromagnetic
field simulator that employs the finite element method. The simulation model consists of a microstrip line with planar input/output
ports and noise absorbing materials of large magnetic loss (magnetic composite sheets containing iron flake particles as absorbent
fillers). The input port is excited by a TEM-mode wave with a characteristic impedance of 50 Ω. Reflection and transmission
parameters (S11 and S21) and power loss are calculated as a function of frequency with variation of the sheet size and thickness. The simulated values
are in good agreement with experimental results and the estimated size dependency of power absorption is consistent with transmission
line theory. It is proposed that the simulation technique can be effectively used in the design and characterization of noise
absorbing materials in high-frequency transmission lines.

Keywordsmagnetic materials-powder processing-electrical properties-computer simulation-noise absorbers

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