undef

s1a-ew-grd-vh-20180117t143557-20180117t143701-020195-022745-002_filter

s1a-ew-grd-vv-20180117t143557-20180117t143701-020195-022745-001_filter

s1a-ew-grd-vh-20180117t143557-20180117t143701-020195-022745-002_winddir

s1a-ew-grd-vv-20180117t143557-20180117t143701-020195-022745-001_winddir