On an expression of antenna factor for transmitting small loop antenna in liquid

To evaluate specific absorption rate (SAR) of radio devices operated in MHz band, a small loop antenna can be used to calibrate a probe for estimating field intensity in the tissue-equivalent liquid. In our proposed method, field intensity radiated by a small loop antenna can be expressed in terms of its antenna factor in transmitting mode. In this paper, distance property of the antenna factor is analytically derived to determine a fitting curve.