Considering "x" runs from 1 to 4 (Figure 3 of main text):

- ds0xa.nc:  CryoSat-2 L1b fully-focused SAR data as downloaded from the ESA GPOD FFSAR service. 
  	     These datasets concern an extended area compared to the one is finally used to compute the FFSAR spectra. 
             (see ds0xb.txt and ds0xc.txt below). The extended window is used to avoid edge effects while filtering
             the data, as described in the main text.

- ds0xb.txt: echo power (Watt)
- ds0xc.txt: Auxiliary data [latitude, longitude, altitude, roll]