Broadband antenna measurement comparisons

Many UWB antennas have been developed for the emerging wireless communications and radio positioning applications. However, how to measure these antennas accurately and efficiently (especially for the radiation pattern, gain and efficiency) over the broad frequency band is a challenging task. In this paper, we report some recent findings obtained by three organisations using different facilities to measure seven selected antennas. It is shown that the measured circuit parameters (such as the input impedance and return loss) are normally very similar, but the measured field parameters (such as the radiation pattern, gain and efficiency) could be very different. The reasons for the discrepancies are investigated and some recommendations are also presented in the paper.