Naval Oceanogr. Office, Stennis Space Center, MS 39522
Energy from a narrow-band pulse interacting with a time varying ocean surface will be spread into upper and lower sidebands. This can be modeled in a range-independent ocean environment using normal modes and a coupling scheme based on first-order perturbation theory. The structure of the scattered signal from the two-dimensional Pierson--Moskowitz surface wave spectrum is presented. The Kraken normal-mode model with environmental inputs from a shallow sea has been used, and a comparison is made with measured data.