Patent ID: 6775617
Filing Date: 2004-08-10
Classification: G01S

Abstract:
A method of determining hydrographic parameters describing in situ a sea swell field including the current and the water depth, by means of a radar device, from analog signal sequences supplied by the radar device, said method comprising the steps of: generating from said analog signal sequences a sequence of digitized signals in spatial coordinates, determining from said sequence of digitized signals in spatial coordinates, by Fourier transformation, a three-dimensional complex-value frequency-wave number spectrum, filtering the frequency wave number spectrum on the basis of the principle of dispersions relation, which interlinks the wave numbers and the frequencies of the sea swell for a localization of sea swell specific parameters by a separation of the signals from noise included in the signal sequence supplied by the radar device, and determining a signal to noise ratio, then determining from the signal to noise ratio the height of the waves and also determining, by localizing the signal coordinates in the surface area defined by the dispersion relationship, parameters describing the surface currents of the sea swell field in a three-dimensional spectral space and the water depth, and employing the phase information concerning the waves monitored in the sea swell field, which is contained in the wave frequency spectrum, to determine the parameters of the sea swell field.