undef

s1b-ew-grd-hv-20170608t160304-20170608t160408-005961-00a758-002_filter

s1b-ew-grd-hh-20170608t160304-20170608t160408-005961-00a758-001_filter

s1b-ew-grd-hv-20170608t160304-20170608t160408-005961-00a758-002_winddir

s1b-ew-grd-hh-20170608t160304-20170608t160408-005961-00a758-001_winddir