In the past few years, radio frequency (RF) devices which are usually used in the vicinity of a human body are increasing. Therefore, it might be expected that pregnant women and their fetuses are exposed to the electromagnetic (EM) waves radiated from the devices, e.g., cellular phone, induction heating (IH) hob, wireless radio terminal, etc. Specifically, wireless radio terminals for business use are used on the abdomen. The EM waves of these devices penetrate to the deep region of the human body because the wavelengths of them operated at several ten to hundreds megahertz are longer than that of the cellular phone. Because of concern that pregnant woman might wear wireless radio terminal on her abdomen in work, the specific absorption rate (SAR) evaluation of the fetus in the pregnant woman is one of the most important researches that needs to be taken under consideration by the world health organization (WHO) [1]. Therefore, it is necessary to evaluate the interaction between the EM waves and the fetus in the pregnant woman. Several papers of evaluating fetal exposure of EM waves with relatively simple numerical models have already been published [2]-[4]. On the other hand, we have developed a fully realistic pregnant woman model. Until now, the fundamental investigations on the evaluation of the SAR were studied using this newly developed pregnant woman model [5]. In this paper, in order to evaluate the SAR in the pregnant woman and her fetus when wearing the wireless radio terminal on her abdomen, the SAR distribution in the fetus is calculated using the numerical model of the pregnant woman [6] by a normal-mode helical antenna (NHA) with a metallic case at 150 MHz.
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