M. R. I. Faruque

Analysis of Electromagnetic Absorption in Mobile Phones Using Metamaterials

Abstract The reducing specific absorption rate with metamaterials attachment is investigated in this article. The finite-difference time-domain method with a lossy-Drude model is adopted in this analysis. The technique of specific absorption rate reduction is discussed, and the effects of attaching location, distance, and size of metamaterials, perfect electric conductor, and materials on the specific absorption rate reduction are investigated. Metamaterials have achieved a 42.12% reduction of the initial specific absorption rate value for the case of 1 gm specific absorption rate and 53.94% reduction for the cases of 10 gm specific absorption rate. These results suggest a guideline to choose various types of metamaterials with the maximum specific absorption rate reducing effect for a phone model.

Study of Specific Absorption Rate (SAR) in the human head by metamaterial attachment

The reduction of Specific Absorption Rate (SAR) with metamaterial is performed by the finite-difference time-domain method (FDTD) with Lossy-Drude model by CST Microwave Studio in this paper. The metamaterials can be achieved by arranging split ring resonators (SRRS) periodically. The SAR value has been observed by varying the distances between head model to phone model, different width, different thickness, and different height of metamaterial design. Metamaterial has achieved 42.12% reduction of the initial SAR value. These results can endow with supportive information in designing the wireless communications equipments for safety compliance.

Electromagnetic (EM) absorption reduction in a muscle cube with metamaterial attachment

The purpose of this paper is to calculate the specific absorption rate (SAR) reduction in a muscle cube with metamaterial attachment. The finite-difference time-domain (FDTD) method has been used to evaluate the SAR in a realistic anatomically based model of the muscle cube. In this paper, we have designed the single-negative metamaterials from a periodic arrangement of split ring resonators (SRRs). By properly designing the structural parameter of the SRRs, the effective medium parameter can be tuned negative at the 900 MHz and 1800 MHz bands. Numerical results concerning the SAR values in the muscle cube in the presence of resonators exhibit significant SAR reduction. These results can provide useful information when designing safety-compliant mobile communication equipment.

A New Design of Metamaterials for SAR Reduction

The purpose of this paper is to calculate the reduction of specific absorption rate (SAR) with a new design of square metamaterials (SMMs). The finite-difference time-domain (FDTD) method with lossy-Drude model is adopted in this analysis. The method of SAR reduction is discussed and the effects of location, distance, and size of metamaterials are analyzed. SMMs have achieved a 53.06% reduction of the initial SAR value for the case of 10 gm SAR. These results put forward a guideline to select various types of metamaterials with the maximum SAR reducing effect for a cellular phone.

A two-component NZRI metamaterial based rectangular cloak

A new two-component, near zero refractive index (NZRI) metamaterial is presented for electromagnetic rectangular cloaking operation in the microwave range. In the basic design a pi-shaped, metamaterial was developed and its characteristics were investigated for the two major axes (x and z-axis) wave propagation through the material. For the z-axis wave propagation, it shows more than 2 GHz bandwidth and for the x-axis wave propagation; it exhibits more than 1 GHz bandwidth of NZRI property. The metamaterial was then utilized in designing a rectangular cloak where a metal cylinder was cloaked perfectly in the C-band area of microwave regime. The experimental result was provided for the metamaterial and the cloak and these results were compared with the simulated results. This is a novel and promising design for its two-component NZRI characteristics and rectangular cloaking operation in the electromagnetic paradigm.

Analysis on the effect of the distances and inclination angles between human head and mobile phone on SAR.

The aim of this paper is to investigate the effects of the distances between the human head and internal cellular device antenna on the specific absorption rate (SAR). This paper also analyzes the effects of inclination angles between user head and mobile terminal antenna on SAR values. The effects of the metal-glass casing of mobile phone on the SAR values were observed in the vicinity of the human head model. Moreover, the return losses were investigated in all cases to mark antenna performance. This analysis was performed by adopting finite-difference time-domain (FDTD) method on Computer Simulation Technology (CST) Microwave Studio. The results indicate that by increasing the distance between the user head and antenna, SAR values are decreased. But the increase in inclination angle does not reduce SAR values in all cases. Additionally, this investigation provides some useful indication for future design of low SAR mobile terminal antenna.

Dual elliptical patch antenna design on low cost epoxy resin polymer substrate material

A new dual elliptical patch antenna is proposed for wideband wireless application. The proposed antenna achieved wideband using internal and external parasitic radiators. The microstrip transmission line fed antenna is consisted of two elliptical radiating patches with two external annular parasitic elements and a partial ground plane. The proposed antenna is printed on epoxy resin reinforced woven glass dielectric material. The antenna structure is planar, and its design is simple and easy to fabricate. Experimental result shows that the designed antenna has achieved an impedance bandwidth of 7.28 GHz (VSWR 2) from 5.72 GHz to 13.0 GHz. Moreover, the antenna shows good radiation efficiency with accacptable radiation patterns within the operating frequency band.

A novel biaxial double-negative metamaterial for electromagnetic rectangular cloaking operation

Abstract This paper presents the design and analysis of a novel biaxial double-negative (DNG) metamaterial for electromagnetic cloaking operation in the microwave range. The proposed metamaterial exhibits DNG characteristics for the three axes (x, y, and z axes) wave propagation through the material. For the z-axis wave propagation, it shows resonance in the X-band and shows DNG characteristics there. Similarly, for the x-axis wave propagation, the material displays resonances in the multi-band (S-, C-, and X-bands) microwave frequency ranges with DNG characteristics at the S-, C-, and X-bands. The material exhibits DNG properties at the S- and C-bands for y-axis wave propagation as well. In the basic design, a new metamaterial structure was developed that was split into two arms. The commercially available finite-difference time-domain (FDTD)-based computer simulation technology (CST) Microwave Studio software was adopted to obtain the reflection and transmission parameters of the unit cell. The metamaterial was then used in designing a rectangular electromagnetic cloaking device where a metal cylinder was perfectly cloaked in the C-band region of the microwave spectra. The metamaterial shows near-zero refractive-index property as well in the cloaked zone. This is a novel and promising design in the electromagnetic paradigm for its biaxial DNG characteristics and rectangular cloaking operation.

Dual wideband n shaped patch antenna loaded with shorting pin for wireless applications

In this paper, a compact N shaped dual band patch antenna loaded by shorting pin is designed. The lessening in patch size is achieved by perturbing the surface current path on the edge of a circular patch antenna by two triangular slots which make the patch as N shaped. Dual wideband is achieved by combining two triangular slots and shorting pin. Simulated results which are carried out by Finite Element Method (FEM) based simulator HFSS such as antenna impedance bandwidth, input impedance and radiation characteristics have been presented and discussed. The lower impedance bandwidth 1.46 GHz covers from 2.89 GHz to 4.35 GHz and the upper impedance bandwidth 2.17 GHz covers from 7.69 GHz to 9.86 GHz. The overall dimension of the antenna is 13×13×1.575 mm3.

A compact disc-shaped super wideband patch antenna with a structure of parasitic element

In this paper, a disc-shaped monopole antenna has been investigated for super-wideband applications with a structure of parasitic element. The proposed SWB antenna consists of disc-shaped patch and a partial ground plane with a structure of parasitic element. The parasitic element consists of 4 rectangular embedded slots on the ground plane. This parasitic element on the ground plane leads the UWB frequency band into the SWB frequency band. This proposed SWB antenna is fed by a microstrip line and is printed on low dielectric FR4 material of 1.6 mm thickness. All the simulations are performed using commercially available, finite element method (FEM) based Ansoft high-frequency structure simulator (HFSS) software and CST Microwave Studio. Measured results exhibit that the proposed disc-shaped antenna shows a wide bandwidth which covers from 2.90 GHz to more than 20 GHz, with a compact dimension of 25 mm x 33 mm for VSWR = 2062. 22) are a good deal sounder than the existing super wideband antennas which make it appropriate for many wireless communication systems such as L, C, X, UWB, Ku, and SWB bands.