An operational wave and surface current monitoring system called WaMoS II is presented. This system is based on a conventional marine X-Band radar and provides three dimensional wave and surface current information, by analysing the temporal and spatial evolution of radar backscatter from the sea surface. Measurement and data analysis take about 2 minutes so that major sea state parameters such as, the unambiguous directional wave number spectrum, the frequency-direction spectrum, the frequency spectrum, the significant wave height, the wave mean direction and angular spreading, the wave period, direction and lengths of the I st and 2 na spectral wave peak, as well as surface current are provided in real time. The system can be operated from coastal sites, moored platforms, as well as from moving vessels. The possibility of unattended operation makes the WaMoS II suitable for long-term monitoring issues. The comparison of different wave parameters derived from radar and buoy measurements yields that the WaMoS II is a reliable wave and current monitoring system especially under bad weather conditions.
Real-time information about the sea state, such as wave height, direction and period, is crucial for coastal protection, as well as offshore operation management (e.g. oil platforms or ships). Therefore considerable interest has been shown lately in the use of remote sensing techniques to measure waves and surface currents. One system to remotely measure the sea state is based on a nautical X-Band radar used for traffic control and navigation purposes. In contrast to buoy measurements, which are based on the analysis of the buoy motion using accelerometer and tilt sensors, radar measurements of the sea state are based on the analysis of the temporal and spatial evolution of the radar backscatter information, received in the near range of the radar (sea clutter).