Temperature increase in the human head due to different models of cellular phones

The temperature increase in a realistic human head model exposed to a handheld cellular telephone, modeled by different cases, is calculated by the FDTD method at 1800 MHz. Maximum temperature increase of 0.019∼0.044°C is found in an inhomogeneous realistic human head model exposed to a handheld cellular telephone or a dipole antenna. It is found that the homogeneous spherical muscle model, exposed to a dipole antenna, has the biggest value of temperature increase (the worst case). A hand holding the cellular telephone can decrease the temperature increase in the human head.