National Institute of Information and Communications Technology, Tokyo 184-8795, Japan.
IEEE Trans Biomed Eng. 2011 Oct;58(10):2740-7. doi: 10.1109/TBME.2010.2103942. Epub 2011 Jan 6.
Cellular phones are used in the vicinity of the human head, resulting in localized exposure to this part of the body. To simulate exposure during cellular phone use, microwave energy absorption should be focused within the head region of laboratory animals. In this paper, we developed an exposure system using a figure-8 loop antenna to permit localized exposure of a rat head to 1500-MHz microwave fields, simulating human head exposure to cellular phones. We have numerically estimated the specific absorption rate (SAR) in a rat exposed to microwave fields via our new exposure system. The high ratio of SAR averaged over the target tissue (i.e., the brain) to that averaged over the whole body suggests that the figure-8 antenna can realize greater localized exposure than the previously used exposure system. We have also confirmed the effectiveness of our proposed system experimentally.
手机在人体头部附近使用，导致身体这一部分受到局部照射。为了模拟手机使用过程中的照射情况，应将微波能量吸收集中在实验室动物的头部区域。在本文中，我们开发了一种使用环形天线的暴露系统，以允许对大鼠头部进行局部暴露于 1500MHz 微波场，模拟人体头部对手机的暴露。我们通过新的暴露系统对暴露于微波场的大鼠的比吸收率（specific absorption rate，SAR）进行了数值估计。目标组织（即大脑）的 SAR 平均值与整个身体的 SAR 平均值的高比值表明，环形天线可以实现比以前使用的暴露系统更大的局部暴露。我们还通过实验验证了我们提出的系统的有效性。
