Dependence of mean effective gain of mobile terminal antennas on side of head

The dependence of radiation pattern, polarization, and mean effective gain (MEG) characteristics of mobile terminal antennas on the side of the head on which the user holds the terminal is considered. For antenna designers and measurement standardization it is important to know if it is necessary to evaluate antenna performance of mobile terminals on both sides of a phantom head. If the measurement or simulation on only one side of the head was sufficient, it would mean a considerable save in testing times and costs. The question is investigated by performing FDTD simulations and measuring a commercial GSM terminal. The results indicate that for some antennas the MEG can be up to 4-5 dB different between the left and the right side of the user´s head at 1800 MHz band and above. Contrary to that the difference in the total efficiency is typically in the order of 0.5 dB only. Thus, if the MEG is used as the antenna performance criterion of a mobile terminal it should be evaluated on both sides of a phantom head at 1800 MHz band and above. If the total efficiency or the total radiated power is the preferred performance criterion, the evaluation on only either side of the head is enough.