undef

s1a-iw-grd-vv-20171011t100951-20171011t101016-018764-01fab1-001_filter

s1a-iw-grd-vh-20171011t100951-20171011t101016-018764-01fab1-002_filter

s1a-iw-grd-vv-20171011t100951-20171011t101016-018764-01fab1-001_winddir

s1a-iw-grd-vh-20171011t100951-20171011t101016-018764-01fab1-002_winddir