undef
s1a-iw-grd-vh-20170905t122424-20170905t122449-018240-01eaa3-002_filter
s1a-iw-grd-vv-20170905t122424-20170905t122449-018240-01eaa3-001_filter
s1a-iw-grd-vv-20170905t122424-20170905t122449-018240-01eaa3-001_winddir
s1a-iw-grd-vh-20170905t122424-20170905t122449-018240-01eaa3-002_winddir