On Free-Space Antenna Reflection Phase Measurements in a Reverberation Chamber

A reverberation chamber is a very useful tool to obtain the radiation efficiency of an antenna. While it has been shown that the magnitude of the reflection coefficient can be obtained from these measurements as well, this has not yet been shown for the phase of the reflection coefficient. This would allow for a full characterization of the antenna's behavior as seen from its input port. In this paper it is shown that the phase of the free-space reflection coefficient can be obtained from measurements in a reverberation chamber by taking the angle of the ensemble average of the individual reflection coefficients. This has been empirically verified by comparing several sets of measurement data from the reverberation chamber to their anechoic chamber equivalents for several antennas.