Numerical investigation of the system validation setup adopted for specific absorption rate measurement

The specific absorption rate (SAR) compliance of wireless communication devices follows a rigorous measurement procedure established by international standards. Prior to the SAR measurement of the device, a mandatory prerequisite is to perform a system verification consisting of a daily system check and a yearly system validation. The system verification set-up consists of a flat phantom filled with tissue equivalent liquid and standard sources such as half-wave dipole antennas fed by a continuous-wave signal at the frequency of operation. For the purpose of the system validation, target SAR values have been previously derived using the finite difference time domain method. A difference of up to ±10 % accepted between the measured and target SAR values. Herein the variabilities of these target SAR values with respect to possible uncertainties of the tissue equivalent liquid are numerically examined.