Comment on ’’Level and zero crossing in volume reverberation signals’’ [R. C. Spindel and P. T. McElroy, J. Acoust. Soc. Am. 53, 1417–1426 (1973)

Abstract

Spindel and McElroy [J. Acoust. Soc. Am. 53, 1417–1426 (1973)] used the zero crossings of a reverberation process to obtain an estimate of the spatial density of scatterers. Errors in their analysis resulted in an intuitively incorrect relationship between the scattering density and the reverberation zero crossing rate. The errors in their analysis are discussed, and, using a different approach, an intuitively correct expression for the zero crossing rate is derived for the special case of a rectangular sinusoidal transmitted pulse and Rayleigh distributed echo amplitudes.