Mobile phone antenna impedance variations with real users and phantoms

This paper shows the differences between mobile phone antenna impedance measurements with real users and phantoms. Three typical mobile phone antennas are measured with 63 volunteers and with phantoms. The results with phantoms are consistent with those obtained with real users, but do not represent the full extent of the changes (when compared to the impedances in free-space). As such, current phantoms are not appropriate for the design of reconfigurable antenna systems that seek to compensate as much of the range of values encountered in practice as possible.