Servizio Comunitario di Informazione in materia di Ricerca e Sviluppo - CORDIS

Mapping the radial change in current field by coherent radar

A coherent radar has the potential to acquire in addition to the signal's amplitude it's phase shift. By receiving the backscatter of a time series of signals from the phases the dominant frequency acquired for each "range bin" can be detected. This dominant frequency is effected by the Doppler shift due to relative movements between the antenna and the sea surface element, which scatters the radar signal. In the application of a radar above water this frequency shift is effected by a series of influences. The most important influence is due to the wind locally acting on the sea-surface by friction and by producing the small capillary waves, which are the scatters for the x-band radar signal.

The method of "mapping the radial change in current field by coherent radar" is based on the assumption that the wind impact to the surface is the same along the radar range. Then the radial changes along the range are only due to effects due to long waves and current shears. In case of the absence of long waves (for example by measurement within tidal inlets) be this method current shear zones can unambiguously be detected.

Reported by

Max-Planck-Strasse 1
21502 Geesthacht
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