Modeling antenna close to the human body

Evaluation of antenna performance needs to be addressed in complex environments rather than in free space. There are many situations when such a need arises. We give examples of evaluation when a human body is in the close proximity of an antenna. In this case, it is also important to evaluate the power absorption in the body in terms of the specific absorption rate (SAR). Two antennas, which show robust performance either on a cellular telephone or on a laptop computer are evaluated. They both operate in two frequency bands allocated for wireless communication. The antenna impedance matching, radiation patterns, and SAR in the user´s head are computed using the FDTD method. Work currently in progress is aimed at evaluation of the SAR when the whole human body is in the near radiation field of a directional antenna. In this case, the exposure cannot be effectively be approximated by a limited number of plane waves, and modeling of the antenna together with the human body leads to a very large computational problem, The solution that is being investigated is modification to the FDTD that allows for exclusion of the antenna from the computational space and representation of its radiation characteristic on the Huygens space in FDTD