A Raw Data Simulator for Ocean Wave Radar Spectrometer

This article presents a new simulator able to generate raw data for ocean wave radar spectrometer (OWRS). Data simulation involves three key procedures: generating 2-D sea wave height, velocity, and acceleration fields by use of a prescribed ocean wave height spectrum; calculating the 2-D sea surface normalized radar cross section (NRCS) field using a quasi-specular backscatter model; and incorporating the generated sea wave height, velocity, and acceleration fields into the radar instantaneous range equation (IRE). Our simulator’s reliability in replicating real-world ocean wave spectra has been confirmed by comparing retrieved wave spectra from simulated OWRS raw data with input reference wave spectra and real-measured radar data. The proposed simulator has several advantages over conventional simulators. Notably, OWRS data generated by the proposed simulator are complex in-phase/quadrature-phase (I/Q) raw data, instead of backscattered power modulation data as simulated by conventional simulators. Our simulator’s other advantages include its ability to reflect the effect of Doppler modulation induced by the motions of the radar platform and the sea waves in the speckle noise spectrum after processing OWRS raw data simulated by the proposed simulator, as well as its ability to embody the effect of range modulation caused by the sea surface topography, including both linear and higher order range modulation effects, in retrieved wave slope spectra. Our simulator offers a powerful tool for understanding complicated interactions between ocean wave dynamics and radar signals. Furthermore, it also provides radar engineers with a cost-effective way to evaluate potential designs for future spaceborne OWRS.