M. I. Hossain

Design and analysis of metamaterial inspired low SAR PIFA for mobile phone

In this paper, a metamaterial embedded planar inverted-F antenna (PIFA) is proposed for cellular phone. A dual band PIFA is designed to operate both GSM 900 MHz and DCS 1800 MHz. The ground plane of conventional PIFA is modified using a double negative (DNG) metamaterial array. The investigation is performed using the Finite Integration Technique (FIT) of CST Microwave Studio. The specific absorption rate (SAR) values are calculated considering two different holding positions-cheek and tilt. The results indicate that the proposed metamaterial embedded antenna produces lower SAR in the human head compared to conventional PIFA. Moreover, the modified antenna substrate leads to slight improvement of the antenna performances.

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.

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.

Low SAR Microstrip Patch Antenna for Mobile Phone

Abstract The aim of this article is to design a new microstrip-fed patch antenna for cell phone applications. The antenna design is composed of slots and FR-4 dielectric substrate fed by a partial ground plane and a microstrip line. The user’s effects on antenna performances are also analyzed using standard SAM phantom. The specific absorption rate (SAR) values of proposed antenna are evaluated for different frequency bands considering cheek position of talk mode. The proposed antenna has an impedance bandwidth (–10 dB reflection coefficients) 100 MHz (0.87–0.97 GHz, lower band), 50 MHz (1.47–1.52 GHz, middle band), and 150 MHz (1.78–1.93 GHz, upper band), which can cover GSM 900 MHz, GPS 1,500 MHz, DCS 1,800 MHz, PCS 1,900 MHz, and GSM 1,900 MHz bands. Moreover, the proposed antenna produces lower SAR values in the human head than that of a dipole and helical antenna.

A Comparative Study of Electromagnetic Absorption of PIFA and Helical Antenna in the Human Head

In this paper, a comparative analysis of electromagnetic (EM) absorption in the human head is presented using planar inverted-F antenna (PIFA) and helical antenna. Both antennas are designed for operating in global system for mobile (GSM) 900 MHz. The EM absorption is evaluated by using two parameters-the peak specific absorption rate (SAR) in the human head tissue and total absorbed power from the mobile phone user. Three different distance configurations are considered to take effects of distance of mobile phone from human head on EM absorption for both antennas. The investigation is based on the finite-difference time-domain (FDTD) method of CST Microwave Studio. The results show that the PIFA provides a significantly lower value of peak SAR in the human head than that of helical antenna. In case of PIFA, total absorbed power is more than 34 % than that of helical antenna.

A combined double H-shaped microstrip patch antenna for X-band operation

In this paper, a combined and compact double H-shaped X-band microstrip patch antenna is designed for bandwidth enhancement. The proposed rectangular antenna is fed by a 50Ω microstrip line. FR-4 (Lossy) is used as a substrate to design the recommended antenna which has a condensed structure of 18×20mm2. The operating zone of this antenna is within 8.4 to 13.6GHz that covers the entire X-band. The gain of the antenna is 5.29dBi which symbolizes its ability to work for mobile communication. This double H-shaped antenna has a return loss is −31.53dBi and an efficiency of 82%. Regarding the antenna, the results are obtained in terms of return loss, gain, radiation pattern and efficiency. The prospective antenna has a compact size, good radiation characteristics and good time domain behavior to mollify the obligation of the recent wireless communication system.

Effective medium ratio obeying multiple octagonal split-ring resonators based metamaterial for tri-band applications

A new tri-band metamaterial unit-cell structure designed and simulated that has multiple octagonal metal rings one inside the other in this paper. The each ring of metamaterial structure delivers a resonance at various frequencies. The number of metal ring resonator has created numbers of resonances. In this paper, different analysis has been performed to verify distinct resonance frequencies, effective medium ratio and effective medium parameters simply by changing the design parameters. Finite-difference time-domain (FDTD) method based Computer Simulation Technology (CST) electromagnetic simulator, which is commercially available is utilized to investigate the design of the metamaterial. The tri-band response has been exhibited of the metamaterial in conjunction with left handed material property over the certain period in the microwave regime. The reported structure has become suitable for S-band (weather radar, radio astronomy, mobile phones, wireless LAN, and GPS), C-band (long distance radio communications), and X-band (satellite communication and space communication) applications and has attained efficient electrically small microwave structure.

Low SAR planar inverted-F antenna for mobile phone

In this paper, a dual band planar inverted-F antenna (PIFA) is proposed for cellular phone applications. The antenna consists of E-shaped patch, shorting wall, feed point and ground plane. A 1.6 mm thicken FR-4 substrate is used in ground plane to reflect the effect of the circuit board. The finite integration technique (FIT) based computer simulation technology (CST) microwave studio is used in major part of this investigation. The results show that the proposed PIFA can cover both GSM 900 MHz and DCS 1800 MHz. The proposed PIFA processes a bandwidth 102.4 MHz (850 MHz to 952.4 MHz) at the lower frequency band and 133.12 MHz (1750 MHz to 1880 MHz) at the upper frequency band. Moreover, the specific absorption rate (SAR) values of PIFA conforms that the proposed antenna exhibit considerably lower SAR compared to a helical antenna.

Design and analysis of double negative metamaterial for microwave s-band

A new double negative metamaterial for S-band applications is presented in this paper. Unit-cell and one-dimensional planar array structure are analyzed. Two array configurations, 2 × 2 array and 4 × 4 array structures of proposed unit cell have been analyzed. The finite integration technique (FIT) based on (CST) Microwave Studio is used in this investigation. The designed unit-cell shows double negative values (both permittivity and permeability) in S band (2.95 GHz to 4.00 GHz). The array configurations shift resonance points of metamaterial structure slightly and hence lead to shift of negative value frequency ranges of effective parameters slightly.

Metamaterial-Embedded Low SAR PIFA for Cellular Phone.

A metamaterial-embedded planar inverted-F antenna (PIFA) is proposed in this study for cellular phone applications. A dual-band PIFA is designed to operate both GSM 900 MHz and DCS 1800 MHz. The ground plane of a conventional PIFA is modified using a planar one-dimensional metamaterial array. The investigation is performed using the Finite Integration Technique (FIT) of CST Microwave Studio. The performance of the developed antenna was measured in an anechoic chamber. The specific absorption rate (SAR) values are calculated considering two different holding positions: cheek and tilt. The SAR values are measured using COMOSAR measurement system. Good agreement is observed between the simulated and measured data. The results indicate that the proposed metamaterial-embedded antenna produces significantly lower SAR in the human head compared to the conventional PIFA. Moreover, the modified antenna substrate leads to slight improvement of the antenna performances.