Mitigation of Human Exposure to Electromagnetic Fields Using Carbon Foam and Carbon Nanotubes

Davide Micheli, Mario Marchetti

Department of Astronautic, Electric and Energy Engineering, Sapienza University of Rome, Rome, Italy.

DOI: 10.4236/eng.2012.412A118                

Abstract

In recent years there has been increasing concern about the possible consequences on human health from exposure to RF fields produced by wireless telecommunication technologies. In this work the coupling between carbon foam and composite materials made of carbon nanotubes and epoxy-resin allows to build a material able to absorb the electromagnetic field thus reducing its intensity in the environment where the mitigation of electromagnetic field is required. The Frequency range considered is 2 GHz - 3 GHz which is the most common frequency band used in wireless network and microwave oven too. Two different kind of heterogeneous materials are designed, one is a layered radar absorbing material made exclusively of epoxy resin and carbon nanotube in different weight percentage, the others are porous carbon foam where the pores are supposed be filled with carbon nanotubes and epoxy-resin. Both type of materials show interesting absorption properties reaching peak of reflection coefficient between –15 dB and –45 dB for a normally incident plane wave.

Keywords

Carbon Nanotube; Carbon Foam; Layered Materials; Radar Absorbing Material; Winning Particle Optimization; Human Exposure Mitigation

Conflicts of Interest

The authors declare no conflicts of interest.

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