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This paper addresses an experiment that was carried out in the North Sea region in the area of the island of Sylt with the aim to study the influence of the maritime boundary layer (MBL) on the propagation of radar signals under low grazing angle geometry. The radar measurements were carried out with the highly versatile MEMPHIS radar operating in sea configuration at X, Ka and W band simultaneously. Concerning the oceanographic and atmospheric characterization, the WTD 71 was responsible for the collection of measurements with a sophisticated suite of sensors partly mounted on the research vessel Elisabeth Mann Borgese. Over a period of four days a valuable dataset was collected including clutter measurements under different geometrical configurations. In this contribution the focus is given to the propagation aspects where dedicated propagation runs were carried out each day

To predict the performance of coastal and shipborne radars, it is essential to assess the propagation characteristics of electromagnetic waves in the maritime boundary layer. To be independent upon environmental measurements, which are generally not as precise and reliable as they have to be for a proper input to simulation programs, usually based upon parabolic equation models, a method to retrieve the refractive index gradients in the low troposphere is the Refractivity from Clutter (RFC) algorithm. The propagation factor is computed from the received clutter power and is iteratively processed in order to retrieve the refractive index profiles. Under a respective French-German technical agreement a measurement program concerning radar propagation in the maritime boundary layer has been initiated, with contributions from ONERA-CERT, DGA MI/TN, Fraunhofer-FHR and the German Technical Center for Ships and Naval Weapons (WTD 71). The paper gives an overview on the RFC met hod with examples from the previous campaigns. It describes the experimental set-up and its methodology