An efficient and straightforward antenna design method is presented that maximizes the ratio of total efficiency specific absorption rate (SAR). This goal achieved with a multiport cluster technique where several ports are excited collectively appropriate feeding weights. These weights found as an eigenvalue solution formulated in terms radiated near-field power antenna. The relies on both (SAR...

Introduction: An increasing number of interventional studies are being developed in which minimally invasive procedures are performed using MRI guidance [1]. Thin and precisely controlled devices, guided wires, and sensors facilitate these during MR scanning. While several studies have reported the MR safety-related issues of metallic devices and wires [2-4], the influences of non-conductive de...

This work presents the design and realization procedure of small implantable antenna for biotelemetry applications. The radiator occupies a volume smaller than 3 cm3 (without its biocompatible insulation), is well matched within the Medical Implanted Communications System band and shows an adequate gain (-28.5 dB) while introduced in the appropriate equivalent body medium. The latter is a homog...

We have investigated a simplification procedure of the Specific Absorption Rate (SAR) compliance test for mobile phones. In this paper, it is shown that maximum averaged SARs of a flat phantom and the SAM phantom are measured and compared for 38 mobile phones in the market in order to investigate on the applicability of using the flat phantom instead of the SAM phantom for the SAR measurement. ...

A meandered and a spiral stacked circular planar inverted–F antennas (PIFAs) are proposed for integration into head–implantable biomedical devices and wireless biotelemetry in the 402–405 MHz Medical Implant Communications Service (MICS) band. Designs only differ in the patch shape, feed, and shorting pin positions, while emphasis is given on miniaturization and biocompatibility. Phantom–relate...

The specific absorption rate (SAR) from mobile telephones at horizontal and vertical positions is investigated in human adult and child heads wearing metal-rim spectacles and having metallic implants. The SAR values calculated by Finite Difference Time Domain (FTDT) method are compared to the actual ANSI/IEEE standards and to the 900/1800/2100 MHz electromagnetic radiation limits according to E...

The paper presents the numerical evaluation of the electroencephalogram (EEG) electrode artifacts that are caused during exposure to electromagnetic fields (EMF), in volunteers study. The scope of the study is to differentially present the electromagnetic (EM) power absorption and local Specific Absorption Rate (SAR) distribution, with and without the electrodes. Versions of two basic exposure ...

Worldwide expansion of mobile phones and electromagnetic field (EMF) exposure has raised question of their possible biological effects on the brain and nervous system. Radiofrequency (RF) radiation might alter intracellular signaling pathways through changes in calcium (Ca(2+)) permeability across cell membranes. Changes in the expression of calcium binding proteins (CaBP) like calbindin D28-k ...

INTRODUCTION: Recent methods of designing RF pulses for multi-coil TX systems have focused on solving regularized systems of equations. These techniques linearize the equations relating the RF waveforms to the resulting excitation and then penalize RF candidates with high peak and root-mean-square (RMS) voltages (VP and VRMS, respectively) in an attempt to limit SAR [1,2]. This is sensible beca...

There has been increasing public concern about the adverse health effects of human exposure to electromagnetic waves. In the radiofrequency and microwave (MW) ranges, elevated temperature (1-2 C) resulting from energy absorption is known to be a dominant factor inducing adverse health effects such as heat exhaustion and heat stroke. Whole-body average specific absorption rate (SAR) is used as a...