undef

s1a-ew-grd-hh-20160603t131950-20160603t132050-011547-011a0b-001_filter

s1a-ew-grd-hv-20160603t131950-20160603t132050-011547-011a0b-002_filter

s1a-ew-grd-hv-20160603t131950-20160603t132050-011547-011a0b-002_winddir

s1a-ew-grd-hh-20160603t131950-20160603t132050-011547-011a0b-001_winddir