Simulation of HF radar cross sections for swell contaminated seas

Based on HF bistatic models for the first- and second-order ocean cross sections developed earlier, a new monostatic cross section model for swell contaminated seas is proposed. The methodology of modelling is to incorporate a Wallop wave spectrum to represent the swell portion while describing the wind wave part with a typical Pierson-Moskowitz spectrum. Then, it is assumed that the total ocean surface is zero-mean Gaussian, and the general expression for the monostatic radar cross section still holds for the combined swell-wind wave spectrum. Simulated results are provided and are seen to be highly consistent with real Doppler spectra. This suggests the contamination of the swell component could be removed with refined inversion algorithms.