tABLE 2. tHE SAMPLE ECHOGRAMS COLLECtED OVER SEA ICE BY VARIOUS GENERAtIONS OF tHE AIRBORNE SNOw RADAR. Distance (m) [εr = 1] Distance (m) [εr = 1] -1 0 1 2 0 Distance (m) [εr = 1] Distance (m) [εr = 1] 0 1 2 -2 -1 0 1 2 0 -2 -1 0 1 2 3 10 20 30 GPS Time (s) 0 Distance (m) [εr = 1] -1 0 1 2 0 -2 -1 0 1 2 3 10 20 30 GPS Time (s) -3 0 -1 0 1 2 0 10 20 30 GPS Time (s) -2 -1 0 1 2 3 0 0 -5 -10 -15 -20 -25 -30 -35 -40 -45 -50 -1 10 20 30 GPS Time (s) -3 -2 0 -5 -10 -15 -20 -25 -30 -35 -40 -45 -50 -1 10 20 30 GPS Time (s) -3 -2 0 -5 -10 -15 -20 -25 -30 -35 -40 -45 -50 -1 10 20 30 GPS Time (s) -3 -3 Distance (m) [εr = 1] -1 0 0 -5 -10 -15 -20 -25 -30 -35 -40 -45 -50 -1 10 20 30 GPS Time (s) -2 3 10 20 30 GPS Time (s) -3 Distance (m) [εr = 1] 0 -3 -2 3 2 3 10 20 30 GPS Time (s) -3 3 2014 NASA OIB Arctic 2-8 GHz 0 1 Normalized Power (dB) 2 0 Normalized Power (dB) 1 -1 Normalized Power (dB) 0 -2 0 -5 -10 -15 -20 -25 -30 -35 -40 -45 -50 -1 Normalized Power (dB) -1 3 2012 NASA OIB Arctic 2-8 GHz Distance (m) [εr = 1] -2 3 2011 NASA OIB Arctic P3 2-6.5 GHz/ 2-6 GHz -3 APPROxIMAtE SYStEM RESPONSE AFtER DECONVOLUtION Normalized Power (dB) -3 3 2010 NASA OIB Arctic 2-6.5 GHz RADAR ECHOGRAM (AFtER DECONVOLUtION) Distance (m) [εr = 1] 2009 NASA OIB Arctic 2.5-7 GHz RADAR ECHOGRAM (BEFORE DECONVOLUtION) Distance (m) [εr = 1] MISSION 10 20 30 GPS Time (s) Before Deconvolution After Deconvolution -0.5 0 0.5 Distance (m) [εr = 1] 1 Before Deconvolution After Deconvolution -0.5 0 0.5 Distance (m) [εr = 1] 1 Before Deconvolution After Deconvolution -0.5 0 0.5 Distance (m) [εr = 1] 1 Before Deconvolution After Deconvolution -0.5 0 0.5 Distance (m) [εr = 1] 1 Before Deconvolution After Deconvolution -0.5 0 0.5 Distance (m) [εr = 1] 1 (Continued) 68 ieee Geoscience and remote sensing magazine june 2017