scholarly journals Anticipated Impact of Hand-Hold Position on the Electromagnetic Interaction of Different Antenna Types/Positions and a Human in Cellular Communications

2008 ◽  
Vol 2008 ◽  
pp. 1-22 ◽  
Author(s):  
Salah I. Al-Mously ◽  
Marai M. Abousetta
Keyword(s):  
Specific Absorption Rate ◽  
Electromagnetic Interaction ◽  
Fdtd Method ◽  
Human Head ◽  
Human Hand ◽  
Model Design ◽  
Antenna Performance ◽  
The Impact ◽  
Internal Antenna ◽  
Difference Time

This paper is intended to investigate intensely the impact of multipossible hand-hold positions on the electromagnetic (EM) interaction of handset antennas and a human by using a finite-difference time-domain (FDTD) method. Candy-bar handsets with different external and internal antenna positions operating in the GSM900, GSM1800/DCS, and UMTS/IMT-2000 bands are hereby simulated with configuration of the most parts in order to achieve the commercially available handset model design. Homogeneous and heterogeneous phantoms both are used to simulate the human head, whereas, a semirealistic model with three different tissues is designed to simulate a human hand holding a set. Both of the antenna performance including the total isotropic sensitivity (TIS) and the specific absorption rate (SAR) in tissues are examined for the different suggested applicable cases, where various positions of antenna, handset and hand are considered in simulations. This simulation study determines that both of the antenna performance and the SAR in tissues significantly alter owing to the positioning of the handset against user's head at different hand levels; where a maximum alteration is observed due to the exposure of handset with internal antenna, as compared with the handset having external antenna.

Investigation of Hand Worn Jewellery Effects on the Specific Absorption Rate in the Human Head and Hand

2011 ◽  
Vol 110-116 ◽  
pp. 4559-4563
Author(s):  
Mohammad Islam Tariqul ◽  
Zainool Abidin Hafizah ◽  
Rashed Iqbal Faruque Mohammad ◽  
Misran Norbahiah
Keyword(s):  
Finite Difference ◽  
Mobile Device ◽  
Time Domain ◽  
Finite Difference Time Domain ◽  
Absorption Rate ◽  
Specific Absorption Rate ◽  
Fdtd Method ◽  
Human Head ◽  
Human Hand ◽  
Difference Time

The presence of hand could alter the energy absorbed in the human head. Hence, a study of the interaction between mobile device antennas and human head in the presence of metallic hand worn jewellery on human hand with different holding ways is investigated. A finite-difference time domain (FDTD) method has been performed by considering an internal PIFA antenna as the radiating source mounted at the top of a commercial clamshell phone positioned nearer the ear. With the introduction of hand-worn jewellery in variation parameters, there were perceptible effects on SAR variation in the human head. SAR distribution in the SAM head was found decreases due to different hand positions. Therefore, the head and in particular the hand may further impairment radiation performance of a mobile device.

Assessment of specific absorption rate reduction in human head using metamaterial

2014 ◽  
Vol 21 (1) ◽  
pp. 79-85 ◽  
Author(s):  
Mohammad Rashed Iqbal Faruque ◽  
Mohammad Tariqul Islam ◽  
Nik Abdullah Nik Mohamed
Keyword(s):  
Absorption Rate ◽  
Specific Absorption Rate ◽  
Structural Parameters ◽  
Fdtd Method ◽  
Human Head ◽  
Ring Resonators ◽  
Specific Absorption ◽  
Difference Time ◽  
Communication Equipment ◽  
Insight Into

AbstractIn this paper, the specific absorption rate (SAR) reduction in human head with metamaterial attachment is calculated. The finite-difference time-domain (FDTD) method has been used to evaluate the SAR in an anatomically correct model of the human head. We designed the double-negative metamaterials by placing periodic array arrangement of split ring resonators (SRRs). By properly designing and tuning the structural parameters of SRRS, the effective medium parameters can be made negative at 900 and 1800 MHz band, as presented in this paper. Experimental results show that, with presence of resonators, SAR reduction in the human head is achievable. These results can provide useful insight into the design of safety-compliant mobile communication equipment.

scholarly journals A Novel Cellular Handset Design for an Enhanced Antenna Performance and a Reduced SAR in the Human Head

2008 ◽  
Vol 2008 ◽  
pp. 1-10 ◽  
Author(s):  
Salah I. Al-Mously ◽  
Marai M. Abousetta
Keyword(s):  
Human Head ◽  
Human Hand ◽  
Hand Model ◽  
Antenna Performance ◽  
Correct Model ◽  
Field Radiation ◽  
Em Field ◽  
Ieee Standard ◽  
Difference Time ◽  
A Current

This paper presents a novel cellular handset design with a bottom-mounted short loaded-whip antenna. This new handset design is modeled and simulated using a finite difference time-domain (FDTD)-based platformSEMCAD. The proposed handset is based on a current commercially available bar-phone type with a curvature shape, keypad positioned above the screen, and top-mounted antenna. The specific absorption rates (SARs) are determined computationally in the specific anthropomorphic mannequin (SAM) and anatomically correct model of a human head when exposed to the EM-field radiation of the proposed cellular handset and the handset with top-mounted antenna. The two cellular handsets are simulated to operate at both GSM standards, 900 MHz as well as 1800 MHz, having different antenna dimensions and intput power of 0.6 W and 0.125 W, respectively. The proposed human hand holding the two handset models is a semirealistic hand model consists of three tissues: skin, muscle, and bone. The simulations are conducted with handset positions based on the IEEE standard 1528-2003. The results show that the proposed handset has a significant improvement of antenna efficiency when it is hand-held close to head, as compared with the handset of top-mounted antenna. Also, the results show that a significant reduction of the induced SAR in the human head-tissues can be achieved with the proposed handset.

Biological effect of SAR on the human head due to variation of dielectric properties at 1800 and 2450 MHz with different antenna substrate materials

2015 ◽  
Vol 22 (4) ◽  
Author(s):  
Mohammad Rashed Iqbal Faruque ◽  
Mohammad Tariqul Islam ◽  
Mohammad Habib Ullah
Keyword(s):  
Dielectric Properties ◽  
Time Domain ◽  
Finite Difference Time Domain ◽  
Biological Effect ◽  
Absorption Rate ◽  
Specific Absorption Rate ◽  
Fdtd Method ◽  
Human Head ◽  
Substrate Material ◽  
Difference Time

AbstractThe aim of this study was to consider a possible discrepancy in electromagnetic (EM) absorption in the human head. The finite-difference time-domain (FDTD) method with the lossy Drude model was adopted in this study. Here, the permittivity and conductivity of all head tissues were increased from 10% to 20% except when not using the same exposure conditions. Recognizable mobile phone frequencies of 1800 and 2450 MHz were studied in this simulation. The increase of up to 20% in conductivity and permittivity and varied substrate material always caused an EM absorption variation of 32.59% for specific absorption rate (SAR) 1 g and 35.25% for SAR 10 g at 1800 MHz, and variation of 20.37% for SAR 1 g and 17.99% for SAR 10 g at 2450 MHz, respectively.

Effects of electromagnetic absorption toward a human head due to variation of its dielectric properties at 900 and 1900 MHz with different antenna substrates

2012 ◽  
Vol 19 (3) ◽  
pp. 271-277 ◽  
Author(s):  
Nur Aisyah Husni ◽  
Mohammad Rashed Iqbal Faruque ◽  
Mohammad Tariqul Islam ◽  
Norbahiah Misran ◽  
Nik Abdullah Nik Mohamed
Keyword(s):  
Dielectric Properties ◽  
Time Domain ◽  
Finite Difference Time Domain ◽  
Specific Absorption Rate ◽  
Fdtd Method ◽  
Human Head ◽  
Helical Antenna ◽  
Electromagnetic Absorption ◽  
Increase With Increase ◽  
Difference Time

AbstractThe aim of this paper is to analyze the effects of electromagnetic (EM) energy absorption at 900 and 1900 MHz when the human head’s dielectric properties are varied. This radiation is measured in terms of specific absorption rate (SAR). The characteristics of the helical antenna and its substrates with variation of the human head dielectric properties were simulated via the finite-difference time domain (FDTD) method using the CST Microwave studio. The human head dielectric properties are manipulated by increasing and decreasing 10% and 20% of each dielectric property. In this study, SAR values increase with increase of the human head’s conductivity, while increase of permittivity and densities decreases it. A helical antenna with a substrate of FR4 resulted in higher SAR values in all frequencies. The head SAR values are higher in the upper frequency exposures. The helical antenna with a substrate of Rogers RO3006 (loss free) was found to be the best-tested substrate, which contributed toward much lower SAR values in all GSM frequency bands.

scholarly journals A New Design of Metamaterials for SAR Reduction

2013 ◽  
Vol 13 (2) ◽  
pp. 70-74 ◽  
Author(s):  
M. R. I. Faruque ◽  
M. T. Islam ◽  
M. A. M. Ali
Keyword(s):  
Finite Difference ◽  
Time Domain ◽  
Finite Difference Time Domain ◽  
Absorption Rate ◽  
Specific Absorption Rate ◽  
Fdtd Method ◽  
Cellular Phone ◽  
Drude Model ◽  
Specific Absorption ◽  
Difference Time

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.

Two Dimensional Photonic Filter with a Circular Resonant Cavity

2013 ◽  
Vol 712-715 ◽  
pp. 1751-1754
Author(s):  
Zhao Xia Wu ◽  
Yuan Long Shao ◽  
Wen Chao Li ◽  
Er Dan Gu
Keyword(s):  
Dielectric Constant ◽  
Resonant Cavity ◽  
Fdtd Method ◽  
Circular Ring ◽  
Two Dimensional ◽  
Transmission Characteristics ◽  
New Type ◽  
Micro Cavity ◽  
The Impact ◽  
Difference Time

A new type of the two dimensional photonic filter which includes two in-line waveguides and a circular ring resonant cavity is presented in this paper. By using Finite Difference Time Domain (FDTD) method, we calculated and demonstrated the broadband frequency response of the filter and analyzed the impact of changing the dielectric constant of the inner rods on the transmission characteristics of the filter. Compared with the transmission characteristics of a micro-cavity,our numerical results show that such a filter can transmit multiple narrowband signals simultaneously. The number of the passbands of the filter increases with the rings of inner dielectric rods in the cavity. The center wavelength of the passbands can be tuned by adjusting the dielectric constant of the whole rods and inner rods without changing the size of the cavity..

scholarly journals Analysis of Specific Absorption Rate on Six Layer Human Head Model

2020 ◽  
Author(s):  
Anand Swaminathan ◽  
Ramprakash A ◽  
Dhejonithan K
Keyword(s):  
Absorption Rate ◽  
Specific Absorption Rate ◽  
Mass Density ◽  
Human Head ◽  
Federal Communications Commission ◽  
Head Model ◽  
Health Issues ◽  
Specific Absorption ◽  
Proposed Model ◽  
The Impact

Despite numerous advantages, mobile phones cause serious health issues to people due to electromagnetic radiation. Various head models already exist to study the impact of radiation on a human head. The accuracy of the measurement of power absorbed by different layers of a head should be high. A new head model with six layers is proposed in this paper. Parameters such as dielectric constant, conductivity and mass density of different tissue layers skin, fat, bone, Dura, cerebrospinal fluid (CSF), and brain are extracted from the Federal Communications Commission (FCC) database. To study the impact of radiation in the proposed model, standard planar inverted F-antennas (PIFA) capable to radiate at 1.7 GHz and 2.4 GHz are used. Simulations are performed using ANSYS Electromagnetics Suite. The analysis shows that the specific absorption rate (SAR) in the brain layer decreased in the proposed model when compared to the existing model.

Investigation of Nanomaterial Dipoles for SAR Reduction in Human Head

Frequenz ◽  
2019 ◽  
Vol 73 (5-6) ◽  
pp. 189-201
Author(s):  
S. Jemima Priyadarshini ◽  
D. Jude Hemanth
Keyword(s):  
Carbon Nanotube ◽  
Human Exposure ◽  
Absorption Rate ◽  
Specific Absorption Rate ◽  
Carbon Nanomaterials ◽  
Human Head ◽  
Human Welfare ◽  
Specific Absorption ◽  
Exposure Analysis ◽  
The Impact

Abstract The Nanomaterial is a pioneer in the field of modern research for its unique properties. Human exposure analysis is inevitable due to the rapid growth in technology. The concern for human welfare indicates a need for reduction of human exposure towards the radiation caused by the devices. The dielectric properties of the nanomaterials can be ideal for exploration in the field of biomedical engineering. Specific absorption rate (SAR) is a vital parameter for exposure analysis. This paper investigates the impact of Nanomaterials on the human exposure analysis. For this purpose, a dipole radiating structure operating at GSM frequency of 900 MHz and 1800 MHz are designed with conventional Copper material and compared with Carbon nanomaterials such as Graphene, Single-walled carbon nanotube (SWCNT) and Multi-walled carbon nanotube (MWCNT) for performance evaluation. Further, the specific absorption rate estimates absorption of radiation in IEEE Sam phantom human head with equivalent tissue properties. The comparison of calculated SAR with the radiating structures that are designed with the equivalent properties of that of Nanomaterials. The evaluation of Nanomaterial Antennas at the center frequency is estimated, and performance is evaluated. The designed Nanomaterials interact with IEEE SAM Phantom and SAR is calculated. The analysis of SAR impact with nanomaterials is investigated in this work.

scholarly journals A Low Profile Ultrawide Band Monopole Antenna for Wearable Applications

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Srinivas Doddipalli ◽  
Ashwin Kothari ◽  
Paritosh Peshwe
Keyword(s):  
Free Space ◽  
Specific Absorption Rate ◽  
Monopole Antenna ◽  
Human Tissues ◽  
Radiation Characteristics ◽  
Wide Bandwidth ◽  
Overall Design ◽  
Antenna Performance ◽  
Low Profile ◽  
The Impact

A low profile pentagonal shaped monopole antenna is designed and presented for wearable applications. The main objective of this paper is to design a miniaturized ultrawide band monopole planar antenna which can work efficiently in free space but also on the surface of the human body. The impact of human tissues on antenna performance is explained using the proposed pentagonal monopole antenna. The antenna is designed with a pentagonal radiator and a matched feed line of 50 ohm and square slots are integrated on defected ground of FR4 substrate with a size of 15 mm × 25 mm to achieve ultrawide band (UWB) performance in free space and human proximity. This overall design will enhance the antenna performance with wide bandwidth ranging from 2.9 GHz to 11 GHz. Specific absorption rate (SAR) of the proposed antenna on dispersive phantom model is also measured to observe the exposure of electromagnetic energy on human tissues. The simulated and measured results of the proposed antenna exhibit wide bandwidth and radiation characteristics in both free space and human proximity.

Sign in / Sign up

Export Citation Format

Share Document