Statistics of Electromagentic Fields within Aperture-Coupled, Nested Reverberant Cavities

An empirical study has been performed to measure the statistics of the fields excited within the inner cavity of overmoded, nested cavities when a small chamber is weakly coupled to a large chamber. Both the external and internal cavities were mechanically tuned during measurements. Two distributions were fit to the measured fields, the double-Rayleigh and exponential. The goodness-of-fit of each distribution was evaluated using rigorous statistical tests. The double-Rayleigh distribution gave a poor fit to the measured field statistics under all conditions considered. The exponential distribution gave a good fit at higher frequencies and with large coupling, indicating that the two chambers are acting as one resonant cavity. These results suggest that a more accurate statistical description is needed when high-precision results are required.