Improved resolution of Geosat altimetry using dense sampling and polynomial adjusted averaging

The altimeter data processing technique presented here improves the spatial wavelength resolution of Geosat ERM by smoothing the 10 Hz data, using measurements of the wave height and averaging repeated (collinear) altimeter measurements. For each repeated track, the residuals between its height profile and the mean height profile were modelled with a third degree polynomial and then subtracted from the data and input in a new averaging. The 10 Hz sampling rate is shown to contain a greater portion of short-wavelength signal than the standard 1 Hz data format. The effective precision is determined to be 1-5 cm, and the along-track wavelength resolution limit is determined to be 19km.