undef
s1a-ew-grd-vv-20180831t033308-20180831t033408-023485-028e87-001_filter
s1a-ew-grd-vh-20180831t033308-20180831t033408-023485-028e87-002_filter
s1a-ew-grd-vv-20180831t033308-20180831t033408-023485-028e87-001_winddir
s1a-ew-grd-vh-20180831t033308-20180831t033408-023485-028e87-002_winddir