Simplified measurement of specific absorption rate for handset antennas by using broadband wave absorber phantom

In this paper, a simplified specific absorption rate (SAR) measurement method using a broadband wave absorber phantom is investigated for handset antennas. The antenna factors are determined by using finite-difference time-domain (FDTD) analysis to obtain the electric-field intensity from the electric voltage of the probe in the wave absorber at 835 and 1,950 MHz. The measured electric-field intensity in the wave absorber phantom in proximity to the handset antennas is identical to the simulated results. The local SARs of handset antennas at each frequency are estimated by using the internal electric-field distribution of the liquid phantom, which is calculated from the surface electric-field distribution of the wave absorber phantom. The validity of the proposed measurement method is verified with the standard measurement results of the local SAR, and the uncertainty of the simplified measurement method is estimated.