On April 1st, 2008, The U.S. Patent Office "stamped" the SUV method for wave measurement with the number US 7,352,651 B2, and a formal patent was issued for this technology. The patent represents the culmination of three years of work where the concept of measuring waves from a subsurface buoy was suggested, developed, and tested in the North Atlantic.
For those not familiar with the SUV method, it may be thought of as a hybrid between the classic PUV (Pressure and two horizontal velocities) and the vertical oriented Acoustic Surface Tracking (AST). What makes this approach special is that it permits mounting an AWAC on a subsurface buoy, which is free to rotate. Buoy rotation precluded using traditional array techniques such as the Maximum Likelihood Method. What this means for the end user is that there is no longer a depth limit subsurface wave measurements. Curious to learn more? A good start is the article that appeared in the February 2008 issue of Sea Technology. A more detailed discussion can be found in the Nortek Bibliography.