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

A diversity antenna for portable telephones, which Is composed of a whip antenna and a planar inverted F-antenna (PIFA) operating at 900 MHz, has been analyzed. The analysis includes the electromagnetic effects of a human operator. Wire-grid analysis yielded the radiation efficiency, mean effective gain, correlation coefficient, and diversity gain characteristics under various incident wave propagation environments with whip length, head-to radio separation, and inclination of the radio from the vertical as parameters. The analysis has been carried out using a homogeneous human phantom model, which includes a head, a hand, and a left shoulder. The effective gain characteristics in multipath propagation environments is described. The analytical results indicate the structural and environmental requirements for designing the diversity antenna with a high diversity effect under practical use conditions.