The use of the expanding-grid FDTD method for simulation of CAD-derived personal wireless telephones

Abstract

This paper discusses techniques for the use of accurate models of wireless communication devices for the determination of SAR compliance. We discuss how computer-aided design and manufacturing files can be used to provide accurate models of both the internal and external components of these types of devices. Results are compared from simulations involving two detailed representations of a commercially available mobile telephone, one of which has been constructed using primitive shapes (e.g., boxes and cylinders), and the other which has been derived from a computer-aided design file. As these simulations require a very high resolution, the use of parallel processing has been applied to the finite-difference time-domain method, to enable solution on an IBM SP-2 parallel supercomputer. As these resources are expensive and not widely available, an expanding-grid finite-difference time-domain code has been developed. This has allowed the use of these high-resolution simulations to be carried out using everyday workstation technology which is widely available. It should be stressed that the numerical simulation techniques discussed in this paper are particularly useful as they allow the compliance testing of a device before it is ever constructed. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 22: 24–29, 1999.