undef

s1b-iw-grd-vh-20170909t110228-20170909t110253-007314-00ce68-002_filter

s1b-iw-grd-vv-20170909t110228-20170909t110253-007314-00ce68-001_filter

s1b-iw-grd-vv-20170909t110228-20170909t110253-007314-00ce68-001_winddir

s1b-iw-grd-vh-20170909t110228-20170909t110253-007314-00ce68-002_winddir