undef

s1a-ew-grd-hh-20151030t141728-20151030t141828-008383-00bd69-001_filter

s1a-ew-grd-hv-20151030t141728-20151030t141828-008383-00bd69-002_filter

s1a-ew-grd-hv-20151030t141728-20151030t141828-008383-00bd69-002_winddir

s1a-ew-grd-hh-20151030t141728-20151030t141828-008383-00bd69-001_winddir