Characteristics of biological tissue equivalent phantoms applied to UWB communications

Previously, the authors studied biological tissue equivalent phantoms able to simulate the electrical constants of the human body in the 3- to 6-GHz band in a single composition ratio. Therefore, in this paper, we examined how to study the antenna characteristics using the phantom when extended to a bandwidth including 900 MHz to 3 GHz and 6 to 10 GHz and performed a quantitative study focusing on the electrical constants of the phantom. The result clearly showed hardly any effect of divergence of the phantom's electrical constants from the target values on the antenna input impedance, radiation efficiency, and radiation directivity. Therefore, in the entire ultra-wideband (UWB), this phantom can be accurately evaluated through antenna characteristic measurements and is clearly effective. Furthermore, differences due to the divergence of the phantom's electrical constants from the target values in the entire UWB bandwidth (3 to 10 GHz) are within +/- 3% for the average local specific absorption rate (SAR) inside the phantom caused by the electromagnetic wave energy radiated from the antenna. (c) 2007 Wiley Periodicals, Inc.