SAR CALCULATIONS IN AN ANATOMICALLY REALISTIC MODEL OF THE HEAD FOR MOBILE COMMUNICATION TRANSCEIVERS AT 900-MHZ AND 1.8-GHZ
SAR CALCULATIONS IN AN ANATOMICALLY REALISTIC MODEL OF THE HEAD FOR MOBILE COMMUNICATION TRANSCEIVERS AT 900-MHZ AND 1.8-GHZ
复制标题
DOI：
10.1088/0031-9155/39/10/003
复制
发表时间：
1994-10-01
影响因子：
3.5
通讯作者：
MANN, SM
中科院分区：
文献类型：
--
作者：
DIMBYLOW, PJ;MANN, SM
一个新的数学模型的头部已被构造从一组序列的MRI切片从一个主题。用时域有限差分法（FDTD）计算了金属盒上的四分之一波长反射器所代表的通用移动的通信收发器的比能量吸收率（SAR），其分辨率为2 mm。天线安装在盒子顶面的中心或角落。所考虑的频率为900 MHz和1.8 GHz。三个照射的几何形状被认为是一个垂直的手机在眼睛前面和垂直和水平方向的一侧的耳朵。考虑了一只手抓住手机的效果。头部模型按比例缩放以代表婴儿的头部，并进行计算的子集以验证婴儿头部中沉积的SAR不超过成人的SAR。结果也提出了半波长偶极子。在900 MHz和1.8 GHz频率下，对于10 g组织平均值，通用收发器在头部侧面（最典型位置）水平方向产生的最大SAR值为2.1和3.0 W kg（-1）/W辐射功率。在900 MHz和1.8 GHz下，1 g组织的相应值分别为2.3和4.8 W kg（-1）/W。然而，如果考虑所有可能的操作条件，则将收发器放置在眼睛前方将分别在900 MHz和1.8 GHz下给出在10 g组织上平均3.1和4.6 W kg（-1）/W以及在1 g组织上平均4.7和7.7 W kg（-1）/W。
A new mathematical model of the head has been constructed from a set of serial MRI slices from one subject. Finite-difference time-domain (FDTD) calculations of the specific energy absorption rate (SAR) have been performed on this model with a 2 mm resolution for a generic mobile communication transceiver represented by a quarter-wavelength monopole on a metal box. The antenna was mounted either at the centre or corner of the top face of the box. The frequencies considered were 900 MHz and 1.8 GHz. Three irradiation geometries were considered, a vertical handset in front of the eye and vertical and horizontal orientations at the side of the ear. The effect of a hand grasping the handset was considered. The head model was scaled to represent the head of an infant and a subset of calculations was performed to verify that the SAR deposited in the infant head did not exceed that in the adult. Results are also presented for a half-wavelength dipole. The maximum SAR values produced by the generic transceiver for the horizontal orientation at the side of the head which is the most typical position, averaged over 10 g of tissue at 900 MHz and 1.8 GHz, are 2.1 and 3.0 W kg(-1) per W of radiated power. The corresponding values over 1 g of tissue are 2.3 and 4.8 W kg(-1) per W at 900 MHz and 1.8 GHz. However, if one were to consider all possible operational conditions, the placement of the transceiver in front of the eye will give 3.1 and 4.6 W kg(-1) per W averaged over 10 g of tissue and 4.7 and 7.7 W kg(-1) per W over 1 g of tissue at 900 MHz and 1.8 GHz, respectively.