
Accession Number : AD0648401
Title : A STATISTICAL THEORY OF REVERBERATION AND SIMILAR FIRSTORDER SCATTERED FIELDS. I. WAVEFORMS AND THE GENERAL PROCESS,
Corporate Author : MIDDLETON (DAVID) CONCORD MASS*
Personal Author(s) : Middleton,David
Report Date : OCT 1966
Pagination or Media Count : 181
Abstract : A theory of reverberation and related firstorder scattered fields is developed, based on the assumption of weak inhomogeneities (i.e., primary scattering only), and a consequent representation in terms of Poisson pointprocesses in space and time. Both surface and volume reverberation are included, separately and together, for general geometries, source and receiver at the same and different locations, and arbitrary transmitting and receiving apertures. A combination of fieldand raytheory is employed to obtain a characteristic scattered waveform, where the inhomogeneous medium is replaced by a homogeneous and isotropic one in which a spatially and temporally random ensemble of point scatterers is embedded. The effects of the scattering mechanism are described generally by a linear, timevarying filter response. The medium itself is seen to be dispersive and is represented by a set of linear (nonseparable, statistical) spacetime operators, by which the signal source and the receiver are coupled to one another, as well as to the pointscatterers.
Descriptors : (*REVERBERATION, *MATHEMATICAL MODELS), STATISTICAL PROCESSES, THEORY, FIELD THEORY, DOPPLER EFFECT
Subject Categories : Statistics and Probability
Acoustics
Distribution Statement : APPROVED FOR PUBLIC RELEASE