The Equivalent Volume of a Reverberation Chamber [Equipped With Suspended Diffusors]

Measurements of the absorption coefficient α in a reverberation chamber show large deviations over the full frequency range. This fact has been proven by many round robin tests over the last few decades [1],[2]. The absorption coefficients measured in different reverberation chambers are not only poorly reproducible but also exceed values above α = 1. Due to the edge effect [3] the absorption coefficient can reach values slightly over α = 1, values of α ≈ 1.6 however are not reasonable from a physical point of view. Past round robin tests tried to eliminate certain kind of measurement uncertainties but the issue has not been resolved. The question still remains if it is possible to measure the true absorption coefficient in a reverberation chamber [4, p.114].