OCEANSAR (Ocean SAR simulator) provides a number of tools to do just that. It provides:
- Routines to calculate a number of directional wave spectra.
- Routines to calculate time-varying (Lagrangian) ocean surfaces applying linear wave theory.
- Code to calculate the instantaneous NRCS for Bragg scatterting and for specular scattering.
- Code to calculate time varying complex scattering coefficients (and their temporal evolution) considering the
various scattering mechanisms considered.
Most of the actual radar simulation has been removed from the current code base. Some reference radar implementations will be re-implemented.
A first iteration the code, under the name Wavesim, implemented in IDL, was implemented by Paco Lopez-Dekker as part of a project for Prosensing Inc., in 2003. Gordon Farquharson fixed some bugs and added support for Elfouhaily's spectrum in order to use the code to simulate FOPAIR acquisitions (note the ironiy that FOPAIR was used to study the surf-zone, where neither the spectral models implemented nor the deep-water linear theory wave model as applicable).
In 2011, the code was ported to Python by Gerhard Marull Paretas, who also added:
- MPI support in order to speed-up the wave simulation.
- Various PO scattering models.
The Python code was used as a base for OASIS, a software tool to simulate along-track-interferometric acquisitions with the future generation European C-band SAR systems (post Sentinel-1) in a project carried out at the Microwaves and Radar Institute (DLR) for the European Space Agency (ESA).
Since then, Paco Lopez Dekker added support for polarimetric acquisitions, and separated OCEANSAR from the radar-specific code in order to be able to open-source the first part.
Things to be done:
- re-implement reference radar simulations (ground based system, and generic SAR system)
- Add interface to external wavespectra, in order to drive the simulations which location and time specific wave models.
- Include models for breaking waves and/or white capping.
- Implement routines to compute expected statistics of radar returns.