Multi-Layered Translucent Wave Absorber Using Carbon Fibers and Applying to Portable Anechoic Chamber

Takenori YASUZUMI  Shunki KATO  Yuya ISHII  Ryosuke SUGA  Osamu HASHIMOTO  

IEICE TRANSACTIONS on Communications   Vol.E95-B   No.12   pp.3830-3836
Publication Date: 2012/12/01
Online ISSN: 1745-1345
DOI: 10.1587/transcom.E95.B.3830
Print ISSN: 0916-8516
Type of Manuscript: PAPER
Category: Electromagnetic Compatibility(EMC)
wave absorber,  carbon fiber,  anechoic chamber,  wideband absorption characteristics,  

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A new wideband wave absorber with translucent structure using carbon fibers is presented in this paper. The absorber is composed of bundled short carbon fibers which are arranged in front of a back metal and a spacer. Absorption characteristics of the one-layered absorber showed that matching frequencies can be controlled by the thickness of the spacer and the length of the carbon fibers. To further improve the characteristics, multi-layered absorbers are designed with the same procedure as one-layered absorber. The designed absorber showed 15 dB absorption characteristics from 1.0 to 10.0 GHz. Then a small anechoic chamber with the inside dimension of 200 cm200 cm200 cm was fabricated using ninety-six proposed absorbers. The electrical power in the chamber was measured at 2.45 GHz and the results showed that the variation of the power was less than 4 dB inside a circle with radius of 60 cm as work space for electromagnetic measurements.