undef

s1b-iw-grd-hv-20160620t061144-20160620t061202-000807-00055a-002_filter

s1b-iw-grd-hh-20160620t061144-20160620t061202-000807-00055a-001_filter

s1b-iw-grd-hv-20160620t061144-20160620t061202-000807-00055a-002_winddir

s1b-iw-grd-hh-20160620t061144-20160620t061202-000807-00055a-001_winddir