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Revista Facultad de Ingeniería - Universidad de Tarapacá

versión On-line ISSN 0718-1337

Rev. Fac. Ing. - Univ. Tarapacá v.13 n.3 Arica dic. 2005

http://dx.doi.org/10.4067/S0718-13372005000300017 

  Rev. Fac. Ing. - Univ. Tarapacá, vol. 13 No. 3, 2005, pp. 122-130

CHIRAL MULTIPHOTON ABSORPTION AND INVERSE SKIN EFFECT IN
WLAN SYSTEMS

Héctor Torres Silva1    Mario Zamorano Lucero1

1 Departamento de Electrónica, Universidad de Tarapacá, 18 de Septiembre 2222, Arica, Chile, e-mail: htorres@uta.cl mhzlucero@uta.cl , Telephone: 56 58 205851 , Fax: 56 58 205189



RESUMEN

Un modelo formado por bioplasma quiral con un conjunto de macromoléculas de ADN, que representa la estructura interna de la cabeza humana, hace posible analizar su comportamiento, cuando es irradiada por campos electromagnéticos de microondas de teléfonos celulares o sistemas WLAN a frecuencias de 2.4 y 5.2 GHz. El método de diferencias finitas en el dominio del tiempo, FDTD, en régimen de multifotones deducido de las ecuaciones de Maxwell es usado. Los resultados numéricos de la taza de absorción específica SAR, muestran el comportamiento de la SAR en función de la potencia de entrada y del factor quiral. Las principales conclusiones de nuestro trabajo son: a) la absorción de microondas es aumentada comparada con modelos clásicos, cuando valores del factor quiral normalizado son del orden de la unidad, que aparecen bajo régimen multifotónico; b) Un fenómeno de efecto pelicular inverso en 5.2 GHz con respecto a una fuente de 2.4 GHz fue observado; c) En la región metamaterial mostramos que la absorción siempre es positiva.

Palabras clave: Quiralidad, tejido cerebral, FDTD, Maxwell, SAR.

ABSTRACT

A model formed by chiral bioplasma with a set of macromolecules of DNA, which represents the human head inner structure, makes possible to analyze its behavior, when it is radiated by a microwave electromagnetic field from cellular phones and WLAN's at frequencies of 2.4 and 5.2 GHz is presented. The finite difference time domain, FDTD, numeric technique is used under multiphoton regime deduced from Maxwell equations. The numerical results of the Specific Absorption Rate, SAR, show the SAR behavior in function of input power and the chirality factor. The main conclusions of our work are: a) the microwave absorption from cellular phones or WLAN's is enhanced, compared with classical models, when values of the normalized chiral factor are of order of one which appear under multiphoton regime ; b) a phenomena like an “inverse skin effect” in 5.2 GHz, with respect to a 2.4 GHz source, was observed. c) In the metamaterial region we show that the absorption rate always is positive.

Keywords: Chirality, brain tissue, Maxwell, FDTD, SAR.



ACKNOWLEDGMENTS

The authors thank the Chilean Agency CONICYT for their financial support FONDECYT No 1040744 and University of Tarapacá Project No 8722-03. Also we greatly appreciate the help received from M. Sc. Enrique Fuentes H.

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Recibido el 10 de junio de 2005, aceptado el 20 de octubre de 2005