The biological effects of the mobile communication systems

随着移动的通信系统的迅速发展，对人体比吸收率（SAR）的评估变得非常重要。利用FD-TD方法计算了无线电话在人体模型中的SAR。这些结果发表在1996年IEICE电子学会会议和1997年IEICE大会的会议记录上。通过人体的运动来评估场分布也是非常重要的。最近，随着无线LAN变得流行，有必要知道天线和人体之间的相互作用。辐射模式和特性由于人体的存在而改变。这种相互作用以及人体中的SAR对于移动的通信系统是特别感兴趣的。为了阐明无线局域网中的传播特性，作者分析和实验研究了天线和用户交互的影响。为解决这类问题，作者提出了一种新的数值方法，即在任意形状的动边界上生成坐标线重合的网格。利用所提出的变换技术，可以在固定的直角坐标系中很容易地求解偏微分方程。最后在固定的直角坐标系下求解运动问题。一些数值计算结果与实验结果进行了比较，并得到了很好的一致性。这些结果在1997年、1999年的电磁理论研讨会上发表，1999年的FESS 99和ICEAA 99发表在1998年的IEICE Trans上，并将于2000年发表在《电磁波和电子系统》（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.