A Numerical Method for Studying Modulation Effects in Radar Observations of the Sea Surface

A numerical method for performing detailed investigations of modulation effects in sea backscattering is presented. The method is based on a combination of numerical hydrodynamic and electromagnetic codes as well as repeated simulations as the spectral content of the sea surface is varied. The results obtained can be useful in separating ldquotiltrdquo and hydrodynamic modulations in computed sea backscattering cross sections, and help to provide some insight into the need for ldquothree-scalerdquo modeling of sea surface returns. Sample results are presented to illustrate the basic process.

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