POWER VARIANCES AND DECAY CURVATURE IN A REVERBERANT SYSTEM

Laboratory measurements of the variance of the power transmission coefficient for ultrasound in a reverberant elastic body are compared with extant theory and found to agree. The theory is then extended to describe the transition between behaviors at low and high modal overlap and to incorporate the effects of decay curvature. The new and more precise theory is found to agree poorly with measurements. Reasons for the poor agreement are discussed; it is concluded that the only viable hypothesis is that mode shape statistics are not described by real Gaussian random functions.