Near-field characterization of reconfigurable narrowband antenna in the proximity of the human body

Abstract

Reconfigurable antennas have been suggested recently for use in various mobile systems. These systems are usually operated in the vicinity of human body, leading to mutual interaction with body tissues. A nondestructive evaluation method is developed to characterize a reconfigurable antenna designed to cover the GSM-900/DCS-1800 bands. Modeling based on FDTD is performed of the antenna in free space and in proximity to the human head. Results reveal frequency shift, and variations in the matching and bandwidth, depending on antenna orientation with respect to the head. Experimental setup is also used to characterize the SAR values in human head. A six-degree-of-freedom robot is implemented to scan a head phantom using specialized sensors and head simulating liquids. The developed system provides a tool for guiding the design of the new category of reconfigurable antennas. © 2009 American Institute of Physics.