undef

s1a-iw-grd-vv-20170823t175019-20170823t175044-018054-01e503-001_filter

s1a-iw-grd-vh-20170823t175019-20170823t175044-018054-01e503-002_filter

s1a-iw-grd-vv-20170823t175019-20170823t175044-018054-01e503-001_winddir

s1a-iw-grd-vh-20170823t175019-20170823t175044-018054-01e503-002_winddir