undef

s1a-iw-grd-vh-20180823t043848-20180823t043913-023369-028ad1-002_filter

s1a-iw-grd-vv-20180823t043848-20180823t043913-023369-028ad1-001_filter

s1a-iw-grd-vv-20180823t043848-20180823t043913-023369-028ad1-001_winddir

s1a-iw-grd-vh-20180823t043848-20180823t043913-023369-028ad1-002_winddir