Low complexity free space impedances measurement of UWB antennas

This work discusses the standard algorithm for measurement of free-space antenna reflection coefficient in a reverberation chamber. This algorithm is explored in the time domain and it is shown that the bandwidth of ultrawideband antennas allows a significant reduction of the number of measurements required. This is because the ultrawideband bandwidth allows us differentiating between the free space antenna reflection coefficient and the backscattering of the environment. The limits on the minimum bandwidth, the distance to the nearest object, and the number of measurement points are discussed and experimental results confirm the methodology. The proposed methodology significantly reduces the duration of the measurement and it is believed to be of interest for industrial production and testing of ultrawideband antennas.