undef

s1b-ew-grd-hv-20170528t164354-20170528t164459-005801-00a2b6-002_filter

s1b-ew-grd-hh-20170528t164354-20170528t164459-005801-00a2b6-001_filter

s1b-ew-grd-hh-20170528t164354-20170528t164459-005801-00a2b6-001_winddir

s1b-ew-grd-hv-20170528t164354-20170528t164459-005801-00a2b6-002_winddir