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Ocean Radar for Monitoring of the Coastal Zones – New Aspects AfterGetting a Worldwide Frequency AllocationThomas Helzel 1 , Matthias Kniephoff 1 , Leif Petersen 1 , Jan Buermans 2 & Eduardo Loos 21 Helzel Messtechnik GmbH, Carl-Benz- Str. 9, 24568 Kaltenkirchen, Germanyhelzel@helzel.com2 ASL Environmental Sciences Inc., Victoria, BC, V8M 1Z5, Canadajan@aslenv.comAbstractFor more than 20 years, Ocean RADARs have proven their reliability for diverse oceanographic applicationpurposes and prediction situations. However, they were operating as systems on experimental license basis only. Atthe World Radiocommunication Conference 2012 (WRC-12), the International Telecommunication Union (ITU) hasfor the first time officially recognized oceanographic RADAR. In the future, primary (under some restrictions) andsecondary frequency bands will be allocated worldwide for these powerful oceanographic sensors. These bandsallow using the instruments for long and short ranges with a spatial resolution of down to 300 m. This initiated thestep forward for Ocean RADAR to transition from experimental systems to operational applications.IntroductionThe Ocean RADAR system is based on over-the-horizon RADAR technology and provides high resolutioncurrent maps for ranges of more than 200 km (Gurgel et al., 1999). The small antennas (2–3 m high monopoles) areset up as an array close to the coastline or on a cliff. The vertical polarised electromagnetic wave is coupled to theconductive ocean surface, will follow the curvature of the earth and will be reflected by the ocean waves (Figure1A).The rough ocean surface interacts with the radio wave and due to the Bragg Effect (ocean waves of half theelectromagnetic wavelength will always create a backscatter of the same phasing) backscattered signals can deliverocean data from ranges of more than 200 km with the smallest signal strength (