undef
s1a-ew-grd-vv-20180831t140403-20180831t140507-023491-028ebb-001_filter
s1a-ew-grd-vh-20180831t140403-20180831t140507-023491-028ebb-002_filter
s1a-ew-grd-vv-20180831t140403-20180831t140507-023491-028ebb-001_winddir
s1a-ew-grd-vh-20180831t140403-20180831t140507-023491-028ebb-002_winddir