Untersuchungen zur Korrelation des spektralen Rauschhintergrundes eines nautischen Radars mit dem Windgeschwindigkeitsvektor

In this publication the dependence of the noise of radar images of the sea surface on the wind speed and direction is studied. The image sequences are transformed with a Fast-Fourier-Transformation in the wavenumber-frequency domain. The two components of the resulting image spectrum, the variance due to the modulation of the waves and the variance of the noise, are separated with a special filter method which is based on the dispersion relation of gravity waves. The separated spectral noise shows a relation to the wind velocity which is described by a linear regression. Additionally the spectral noise depends on the angle between the wind direction and the antenna look direction, called azimuth angle. The variance of the spectral noise has for an azimuth angle of 180 (antenna look direction against the wind direction) a maximum and decreases for greater and smaller azimuth angles. The results of the spectral domain are confirmed by investigations in the spatial domain. (orig.)Available from TIB Hannover: RA 3251(98/E/62) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman