Field and intensity correlation in random media

We have obtained the spectral and spatial field correlation functions, C-E(Delta omega) and C-E(Deltax) respectively, from measurement of the microwave field spectrum at a series of points along a line on the output of a random dielectric medium. C-E(Delta omega) and C-E(Deltax) are shown to be the Fourier transforms, respectively, of the time of Right distribution, obtained from pulsed measurements, and of the specific intensity. Unlike C-E(Delta omega), the imaginary part of C-E(Deltax) is shown to vanish as a result of the isotropy of the correlation function in the output plane. The complex square of the field correlation function gives the short-range or C-1 contribution to the intensity correlation function C. Longer-range contributions to the intensity correlation function are obtained directly by subtracting C-1 from C and are in good agreement with theory.