Effects of the metallic spectacles with braces added on Specific Absorption Rate (SAR) exposed to frontal radiation sources

Abstract

The investigation on the changes of Specific Absorption Rate (SAR) inside the head due to metallic straight pin with simple braces added is presented in this paper. The finite integration in time domain (FIT) computer simulation technique was used in this investigation. The head is irradiated by dipole sources in front of the Specific Anthropomorphic Mannequin (SAM) face. Parametric studies show that 1 gram SAR at 900MHz is slightly reduced. However at 1800MHz, it decreased if pin lengths were varied longer than dipole and it can increase if pin is shorter or both has the same length. I. INTRODUCTIONNowadays, with more open source for mobile applications listed in market and larger screens, mobile communication equipment (MCE) used in frontal of the face has been increasing significantly. Numerous studies have examined the interaction between the electromagnetic fields radiated by the antenna that may also couples with metallic objects and the results seem to suggest that metallic objects could increase the SAR [1]- [4]. Whittow [4], found metallic braces modelled with closed mouth could double the 1g and 10g SAR. In this current paper, a straight metallic pin near the eye representing a metallic spectacle employed together with another two straight metallic pins near to the mouth as a simple geometrical representation of the orthodontist braces. The electric field distribution within the head (without braces) is simulated and compared with the cases when the braces are worn and are visible while talking (open mouth). The authors present results from a study of the effects of SAR from a single metallic pin compared with a pair of metallic braces added to the mouth illuminated by RF sources (900MHz and 1800MHz).

The Influence of Human Head Model Wearing Metal-Frame Spectacles to the Changes of Sar and Antenna Gain: Simulation of Frontal Face Exposure

“…Table 2 shows the parameters of the head simulating liquid (HSL) used for both of the GSM frequency ranges used. The results for all simulations were normalized to 1 Watt accepted power, and the worst case scenario was assumed to be the case in which the mobile phone's antenna required more power when operated at a long distance from base stations [31]. This SAM phantom head model was a good choice for observing radiation patterns and for fast calculations, but its accuracy was suboptimal.…”

A Study of specific absorption rate in human head due to electromagnetic exposure to 4G signals

“…Specific absorption is defined as the quotient of the incremental energy (dE) absorbed by an incremental mass (dm) contained in a volume (dV) of a given density (ρ). However, specific absorption rate (SAR) is defined as the rate of energy (dE) absorbed or dissipated in an incremental mass (dm) contained in an incremental volume (dV) of a given density (ρ) [1]- [3], [5]- [10], [15]- [31]. Mathematically, SAR can be expressed in watt per kilogram (W/kg) as However, the SAR for specifying the radiofrequency absorption by tissue can be calculated at any location in the tissue from the electric field (E) as shown below:…”