Bound wave effects in microwave and acoustic backscatter from rough water surfaces

Simultaneous backscattering measurements with radar and sonar in the large wind wave facility in Marseilles, France shows that bound and free waves coexist on the water surface. By observing the surface from above and below, we were able to show definitively that the bound waves ride on the front face of the dominant wave in the tank. Because of the large width of the tank, we were able to vary the azimuth angle of both the radar and sonar, which viewed a common surface area, and observe the dependence of both free and bound waves on azimuth angle.