SMOS Rotation of Polarisation Coordinate Frame Between Antenna Frame and Surface Frame SMOS Polarisations: From antenna frame to surface frame –> the tool you wanted to have! 23 novembre 2010 As you know there is a significant difference between the polarisations as seen at antenna level and those at surface level. To go from one to the other it is a very straightforward rotation… But a bit tricky though. As we have developed several such tools for our own purposes we though that to avoid duplication of efforts (and reduce aspirin consumption) many might appreciate having a ready made tool! So Delphine Leroux looked at what we had in store, selected the most generic and did what was necessary to have a rather robust and hopefully exact matlab tool, directly interfaced with the RWAPI code developped by Array for SMOS. This tools has been tested by several hand picked users and seems now ok. So here it is! You will find the matlab routine together with a small example (read me file) in the software page. Because of the uncertainty on rotation angle, we can not asssure the results will be correct for L1C product before the 344 prototype version (July 6th, 2010). Feel free to use and abuse but remember it is given as it is… and not hot line help please. But if you find a bug, a probelm etc, please tell us so that we can improve. Enjoy! Delphine Leroux and the CESBIO Smos Team Hydro