Sains Malaysiana 41(6)(2012): 779-785

Analisis Pengurangan Kadar Penyerapan Spesifik dalam Kepala Manusia

Menggunakan Bahan Ferit dan Metabahan

(Analysis of Specific Absorption Rate (SAR) Reduction in the Human Head UsingFerrite

Materials and Metamaterial)

Norbahiah Misran, Iqbal Faruque, Nurul Hafizah Mohd Hanafi, Farizah Ansarudin* & Mohd Faisal Ibrahim

Jabatan Kejuruteraan Elektrik, Elektronik dan Sistem, Fakulti Kejuruteraan dan Alam Bina

Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor D.E. Malaysia

Mohammad Tariqul Islam

Institut Sains Angkasa, Aras 2, Fakulti Kejuruteraan dan Alam Bina, Universiti Kebangsaan Malaysia

43600 UKM Bangi, Selangor D.E.

Received: 2 Februari 2011 / Accepted: 20 Januari 2012

ABSTRAK

Kertas ini membincangkan kaedah untuk mengurangkan kesan interaksi gelombang elektromagnet dengan kepala manusia menggunakan bahan ferit dan metabahan. Pengukuran pengurangan bagi Kadar Penyerapan Spesifik (SAR) menggunakan bahan ferit dan metabahan telah dilaksana dengan kaedah domain-masa perbezaan-terhingga (FDTD) model Lossy-Drude melalui perisian CST Microwave Studio. Metabahan dibentuk dengan menyusun penyalun cincin terpisah (SRRs) secara berkala. Nilai SAR diukur pada beberapa nilai jarak antara model kepala dengan telefon, kelebaran, ketebalan dan ketinggian bahan ferit dan metabahan. Hasil kajian menunjukkan bahawa nilai SAR1g telah berkurang kepada 1.043 W/kg dengan menggunakan bahan ferit dan 1.161 W/kg dengan menggunakan metabahan. Bagi SAR10g, nilai SAR menurun kepada 0.676 W/kg menggunakan bahan ferit dan 0.737 W/kg dengan menggunakan metabahan. Keputusan bagi nilai SAR dalam kepala manusia dengan kehadiran SRR yang membentuk metabahan telah dianalisis untuk menentusahkan kesan bagi pengurangan SAR ini. Keputusan analisis ini boleh memberikan maklumat yang dapat membantu dalam reka bentuk peralatan komunikasi tanpa wayar bagi mematuhi peraturan keselamatan.

Kata kunci: Antena; bahan ferit; Kadar Penyerapan Spesifik (SAR); kaedah FDTD; metabahan

ABSTRACT

This paper discusses the method to reduce electromagnetic wave interaction with the human head using ferrite and metamaterials. The measurement of Specific Absorption Rate (SAR) reduction with ferrite materials and metamaterials was performed using the finite-difference time-domain (FDTD) method with Lossy-Drude model via CST Microwave Studio software. The metamaterials was formed from a periodic arrangement of the split ring resonators (SRRs). The SAR values were measured at several distances between the head model and the phone, widths, thicknesses, and heights of the ferrite and metamaterial. The research results indicated that the SAR1g value has been reduced to a value of 1.043 W/kg using ferrite material and 1.161 W/kg using metamaterials. For SAR10g, the value decreases to 0.676 W/kg using ferrite material and 0.737 W/kg using metamaterials. Numerical results of the SAR values in a human head with the presence of SRRs as metamaterials are shown to validate the effect of SAR reduction. These results can provide useful information in the design of the wireless communication equipment for safety compliance.

Keywords: Antenna; FDTD method; ferrite materials; metamaterial; specific absorption rate (SAR)

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*Corresponding author; email: izah@eng.ukm.my