undef
s1a-iw-grd-vv-20170907t103020-20170907t103045-018268-01eb76-001_filter
s1a-iw-grd-vh-20170907t103020-20170907t103045-018268-01eb76-002_filter
s1a-iw-grd-vh-20170907t103020-20170907t103045-018268-01eb76-002_winddir
s1a-iw-grd-vv-20170907t103020-20170907t103045-018268-01eb76-001_winddir