Millimeter-wave radar back-scattering from water waves

The paper describes the design and operation of a new ultra-high resolution MM-wave FMCW synthetic aperture radar, which has been used for wave-tank experiments to investigate the imaging mechanisms of internal waves in SAR images and the backscattering mechanisms of a water surface at MM-wave. Two series of experiments have been carried out in LEGI, Grenoble, with mechanically generated waves and at the IfM, Hamburg University, with wind waves. The new results we obtained from our data are presented and analysed, considering the nature of the scatterers involved. It is concluded that the MM-wave radar is sensitive to very small hydrodynamic modulations and freely propagating Bragg waves.