Numerical Simulation of Microwave Backscattering from Sea Surface

Abstract

In order to improve the measurements of the sea surface by active microwave remote sensing, it is necessary to understand the mechanism of microwave backscattering from the sea surface. The phenomenon of microwave scattering at the sea surface is complicated and not clarified enough. The purpose of the present research is developing time domain numerical simulation technique to clarify backscattering mechanisms and evaluate sea surface observation methods. In the simulation,backscattering coefficients and Doppler spectra can be obtained. Physical optics approximation is applied to calculate scattering electric fields. The validity of the simulation has shown by comparing with the results of the experimental basin.Microwave backscattering has been simulated under the same condition as the experiment. The results indicate that the simulation technique is effective to calculate microwave backscattering from the water surface changing in time.As an application of the simulation, we have simulated microwave backscattering with a pulse Doppler radar. Radar images of backscattering coefficient and Doppler velocity have been generated. The results show that radar images of Doppler velocity are more effective than images of backscattering coefficient for sea surface observation.