FDTD Simulation of a Mobile Phone Operating Near a Metal Wall

Abstract

<p class="MsoNormal" style="text-align: left; margin: 0cm 0cm 0pt; layout-grid-mode: char;" align="left"><span class="text"><span style="font-family: ";Arial";,";sans-serif";; font-size: 9pt;">The Finite-Difference Time-Domain (FDTD) is the most often used method for evaluating of electromagnetic fields in human tissue. This paper presents a study of heating effects resulted from using a mobile phone operating near a metal wall. The finite-difference time-domain (FDTD) simulation scheme was used in the simulation. The simulated physical domain consists of a dipole antenna, a highresolution human head model and a metal wall enclosed by the Perfectly Matched Layer (PML). In this case, the PML acts as an electromagnetic field absorbing layer and was backed by a perfect electric conductor. An antenna model operated at 900 and 1.8 GHz was used in the simulation. The Specific Absorption Rate (SAR) was computed and averaged on a tissue mass of one gram and ten grams, SAR 1-g and SAR 10-g, respectively. The main purpose of the present research is to compare SAR resulted from a mobile phone operated at two different frequencies (900 MHz and 1.8 GHz) in the close proximity to a metal wall. Also, average powers (P</span></span><span class="text"><span style="font-family: ";Arial";,";sans-serif";; font-size: 7.5pt;">avg</span></span><span class="text"><span style="font-family: ";Arial";,";sans-serif";; font-size: 9pt;">) obsorbed in various human tissues were computed with a distance between an antenna and a metal wall (Δ<em>l</em>) as a varying parameter. Results from the simulation show that the computed SAR 1-g and SAR 10-g values are not exceed the limitation values established by various standard institutes. Also, the average power absorbed in all tissue models with a mobile phone operated at 1.8 GHz has an average power lower than those operated at 900 MHz except for the average power absorbed in muscle (7<Δ<em>l< 9 cm) and eye (7< </em>Δ<em>l</em><11cm).</span></span><span style="font-family: ";Arial";,";sans-serif";; font-size: 9pt;"></span></p&gt

An improved FDTD model for the feeding gap of a dipole antenna

“…Although, its results are occurring in time domain, its results can be converted to frequency domain by Discrete Fourier Transform (DFT). For almost all of the FDTD simulations, Perfectly Matched Layer (PML), which is an artificial absorbing layer, is used to form the boundary condition for the FDTD scheme [4][5][6][7][8]. For a dipole simulation, the feeding point or the one-cell gap is the input source part of the dipole in the simulation.…”

Study of Em Wave Absorption and Shielding Characteristics for a Bonsai Tree for GSM-900 Band

“…From the converged solution, SAR induced inside the Bonsai tree model is obtained using the following equation [19][20][21][22]: (15) where, E x , E y and E z are the magnitudes of the E field components (V/m), and σ is the conductivity (S/m) of the (i, j, k)th FDTD cell.…”

FDTD Simulation of a Mobile Phone Operating Near Metals

“…Also, for comparison, results of FDTD simulation with the metal wall model were presented in [1]. The one metal cell model is shown in Fig.…”

“…In general, mathematical theory and various implementations of FDTD were presented in [1]- [11]. Also, for comparison, results of FDTD simulation with the metal wall model were presented in [1].…”

“…Sometime, the metallic case and the plastic case with metallic decorations can be a reflector of the built in antenna by accident. This paper assumes the metallic case is something like an infinite metal wall [1] located at 0-1 cm from the antenna. This implies that the plastic case with metallic decorations is something like a one metal cell located at 0-1 cm from the antenna.…”