Structure of tropospheric inhomogeneities as deduced from interferometric measurements

A method for identifying the geometry of atmospheric irregularities is illustrated and its use in an experiment is described. The method consists in determining the spatial statistics of the field in a transverse plane at the receiving end of a line-of-sight propagation path. The spatial statistics are derived by measuring the degree of coherence for points aligned in vertical and horizontal directions. By the anisotropy of the coherence, the geometrical structure of irregularities of the part of atmosphere which has been passed through is inferred. By taking advantage of the observation of other quantities that the interferometric technique can provide, the diverse mechanisms of propagation are recognized, thus confirming the existence of a given structure of irregularities. The experiment has been conducted at X-band over a 37.5 Km path, and data which have been obtained from it furnish, among other things, information on the probability of occurrence of meteorological conditions related to the observed structures of irregularities.