undef
s1a-iw-grd-vh-20190929t124223-20190929t124248-029236-03524a-002_filter
s1a-iw-grd-vv-20190929t124223-20190929t124248-029236-03524a-001_filter
s1a-iw-grd-vv-20190929t124223-20190929t124248-029236-03524a-001_winddir
s1a-iw-grd-vh-20190929t124223-20190929t124248-029236-03524a-002_winddir