1、 1 手机电磁辐射定量分析研究 摘 要 随着移动通信技术的发展,手机等移动通信终端设备在公众中的使用已经越来越普及。由于手机在通话过程中必然要产生一定的电磁辐射,这些辐射或多或少对人体的健康带来一定的影响。因此手机对人体的电磁辐射作用已经越来越受到公众的广泛关注。目前,比较公认的人体电磁辐射的计算值是比吸收率 SAR(Specific Absorption Rate)。比吸收率根据不同介质中电场强度的大小来相应的衡量电磁辐射的程度。国外对于比吸收率的研究从上世纪七十年代已经开始,目前相当一部分国家已经提出或制定 了 SAR 方面的标准和规 范 。对于电磁辐射问题,国内外已经进行了大量的研究工作
2、。本篇论文利 用 电 磁 场 计 算 的 常 用 方 法 时 域 有 限 差 分 方 法 (Finite Difference Time Domain)对 SAR 进行计算。 本文首先介绍手机电磁辐射、比吸收率的基本概念,分别讨论了频域和时域、有限差分法的基本原理,通过基本原理推导出有关手机电磁辐射的基本方程,最后用近似建立的模型进行实验计算,并且比较了不同部位 SAR 值的变化情况。得出了人头部的局部 SAR 分布不均匀。在头模型内最大电场强度出现在距离天线馈电点最近的地方。距离 天线相对较远的地方,场强较小。沿头部表皮区域吸收比率 SAR 值较大,而在头内部 SAR 值较小。 关键词: 电
3、磁辐射,手机,比吸收率 SAR,时域差分法 II QUANTITATIVE ANANLYSIS OF CELL PHONE ELECTROMAGNETIC RADIATION ABSTRACT With the development of the mobile communication technology, mobile phone and other mobile communication terminals become more and more popular in public. Because in the process of the calling, there mus
4、t have certain electromagnetic radiation produced or received by the terminal. These radiation may bring the health hazards to human beings more or less. So the electromagnetic radiation from mobile to human catches much more publics concerns today At present, the commonly recognized value for elect
5、romagnetic radiation to human is SAR(Specific Absorption Rate) This value comes from the value of the electric-field intensity to evaluate the electromagnetic radiation degree. The study of SAR began from the 1970s abroad now a lot of countries have already presented some rules or guidance on SAR Ma
6、ny researchers have been done about SAR both in and out of the China. So this paper discusses the mobile electromagnetic radiation from several unique aspects. The numerical simulations for SAR use the FDTD (Finite Difference me Domain) which is commonly used in electromagnetic field calculation. Be
7、cause of the many orientations of SAR research, this paper focuses on the following aspects: First, introduce mobile phone electromagnetic radiation, the basic concept of specific absorption rate; second, respectively, discussed the frequency and time domain, the basic principles of finite difference method. Derived by the basic principles of mobile phone electromagnetic radiation on the basic equation. Finally, the approximate calculation of the model experiment, and compare the SAR values in different parts of the change. The head obtained is difficult to