An analysis of the performance of a handset diversity antenna influenced by head, hand and shoulder effects at 900 MHz

The purpose of this work is to make a wire-grid analysis of a diversity antenna comprising a whip antenna and a built-in planar inverted F antenna (PIFA) to include the electromagnetic effects of a human operator and to evaluate the diversity performance with regard to the head-to-radio separation under various incident radio wave environments. Investigations are also made on the power absorbed in the head, hand and shoulder, on the power loss due to impedance mismatch, and on the dissipated power in a non-excited element when the head-to-radio separation is changed. From the results, a mechanism for changing radiation efficiency is explained.