SPACE-TIME CORRELATION FUNCTION OF SCATTERED FIELDS

A method for finding the statistical properties of scattered fields caused by scatterers is established. The chief points of this method are the applications of the theory of random time-varying networks and the theory of streams of random events in queueing theory. An expression of space-time correlation function of scattered fields is established by this method. More factors, such as the random motions of scatterers, the statistical dependence between these motions, the inhomogeneities （including stratified inhomogeneity） of propagation medium, the dispersion and absorption by the medium, the differences between scatterers, and the like, are taken into account in this expression. These factors are always unnegligible in most practical problems. Moreover, the functional forms of transmitted signals, directivity of radiation, spatial distribution of scatterers, scattering coefficients, etc. are unrestricted in this expression.
As an example, the statistical properties of back scattering of underwater sound by the bubbles, the random motions of which are caused by the waves, are studied.