Fdtd Computation for Large-scaled Numerical Dosimetry on Parallel Personal Computers

1. Introduction Since it is very difficult to quantify microwave absorption directly in a living human, dosimetry is forced to rely mainly on computer simulation with high-resolution numerical human models obtained from magnetic-resonance imaging (MRI) or computed tomography (CT) scans. The Finite-Difference Time-Domain (FDTD) method [1] is currently the most widely accepted means for the numerical dosimetry. By discretizing space into a number of cells, and by assigning each cell the corresponding permittivity and conductivity, this method offers great flexibility in modeling the heterogeneous structures of anatomical tissues and organs. However, The use of millimeter high-resolution human models becomes difficult as a huge amount of memory for computer simulation prohibits their use. In this paper, a parallel FDTD computation system is developed using Linux-based personal computers. The parallelism is based on the Message Passing Interface (MPI) library [2]. Its performance is tested and an application to examine the whole-body effect on the user head dosimetry for a mobile phone is shown.