In 1992, Luebbers et al. [189] and Chen et al. [190] analyzed hand-held antennas using an FDTD model of a monopole antenna on a conducting or dielectric box. Toftgård et al. [191] calculated the effects the presence of a person has on the radiation from such an antenna. In 1994, Jensen and Rahmat-Sammii [192] presented results for the input impedance and gain of monopole, PIFA, and loop antennas on hand held transceivers. The interaction of a hand-held antenna and a human were also studied by Jensen and Rahmat-Samii [193]. Also in 1994, Chen and Wang [194] calculated the currents induced in the human head with a dipole antenna model for a cellular phone. Recently, Martens et al. [195] have used a dipole model and a full model for a hand-held antenna to compute the fields induced in the human head.