Special Aspects of Ultra-Short Radio Wave Propagation above the Sea Surface. Theoretical Background and Experimental Results

Anomalous propagation of radio waves above the sea surface depends primarily on the existence of marine boundary layers. Meteorological data that characterizes the marine boundary layers can be analytically described by duct profiles. The following types of atmospheric ducts are well known: evaporation duct, surface-based duct, surface duct and elevated duct. The major problem of analytical description of duct profiles lies in acquisition of vertical distribution of air temperature, relative humidity, atmosphere pressure and refractivity index. This paper examines one of the possible examples of acquisition of data about vertical distribution of air temperature, relative humidity and atmosphere pressure with the use of helicopter and a network of multisensors in the area of the Gulf of Finland. The new method of estimation of radio wave propagation characteristics is also presented. The presented method allows to examine patterns of radiolocation field forming under different atmospheric conditions. The results obtained by this method may be applied in the next generation of theoretical research and may be used for practical purposes in cell networks and wideband radio technologies that are, in turn, widely applied in coastal businesses, sea transport, sea surveillance and identification systems and in many other areas.