The biological effects of the mobile communication systems

随着移动通信系统的迅速发展，评价人体的比吸收率(SAR)变得非常重要。用FD-TD方法计算了贴近头部放置的无线电话在人体模型中的SAR。这些结果发表在1996年IEICE电子学会会议论文集和1997年IEICE大会论文集上。通过人体的运动来评价场的分布也是非常重要的。近年来，随着无线局域网的普及，有必要了解天线与人体之间的相互作用、辐射方向图和特征随人体的存在而改变的情况。这种相互作用以及人体内的SAR对移动通信系统特别感兴趣。为了弄清无线局域网中的传播特性，作者对天线和用户交互的影响进行了分析和实验。为了在数值上解决这些问题，作者提出了一种新的网格生成的数值方法，即坐标直线与任意形状的动边界重合。利用本文提出的变换技术，可以非常方便地在固定的直角坐标系中求解偏微分方程组。最后，我们可以在固定的直角坐标系中解决运动问题。将部分数值计算结果与实验结果进行了比较，得到了较好的一致性。这些结果分别于1997年、1999年和1999年在IEICE Trans上发表在1997年、1999年的FESS99和ICEAA99上，并将于2000年发表在《电磁波与电子系统》(EW&ES)上。

As there has been a rapid increase in a mobile communication systems, it becomes important to evaluate the Specific absorption rate (SAR) in human body. The SAR in a human body model from a wireless phone placed closed to the head is calculated by FD-TD method. These results were presented in Proceedings of the 1996 Electronics Society Conference of IEICE and Proceedings of the 1997 IEICE General Conference. It is also very important to evaluate the field distribution by the movement of the human body. Recently as the wireless LAN becomes popular, it is necessary to know the interaction between the antenna and the human body The radiation pattern anti the characteristics are altered by the presence of the human body. This interaction as well as SAR in the human body are of particular interest for mobile communication systems. To clarify the propagation characteristics in the wireless LAN, the author examined the Influence the antenna and the user interactions analytically and experimentally. To solve these problems numerically the author has proposed a novel numerical procedure of grid generation having coordinate line coincident with an arbitrarily shaped moving boundary. By using the presented transformation technique, partial differential equations can be solved very easily in the fixed rectangular coordinate system. Finally we can solve the moving problem in a fixed rectangular coordinate system. Some numerical results are compared with the experimental ones and excellent agreement between them are obtained. These results were presented at The Electromagnetic Theory Symposium in 1997, 1999, FESS99 and ICEAA99 in 1999 published in IEICE Trans, in 1998 and will be published in Electromagnetic Waves and Electronic Systems (EW&ES) in 2000.