In this paper, we will study the influence of nonlinear waves (breaking waves) on the EM signature of a sea surface in bistatic case (forward propagation). Indeed, we will start the temporal numerical analysis of the scattering coefficient σHH of breaking waves in bi-static configurations. Then, we will show the first experimental validation of the numerical results using well calibrated measurements of precise breaking wave profiles. These experimental measurements have been carried out in X-band in our anechoic chamber(E³I²-EA3876-ENSTA BRETAGNE). In this work, we will consider the sea surface as a perfect conductor.