undef
s1b-iw-grd-vh-20170923t104439-20170923t104504-007518-00d45f-002_filter
s1b-iw-grd-vv-20170923t104439-20170923t104504-007518-00d45f-001_filter
s1b-iw-grd-vv-20170923t104439-20170923t104504-007518-00d45f-001_winddir
s1b-iw-grd-vh-20170923t104439-20170923t104504-007518-00d45f-002_winddir