undef

s1a-ew-grd-vv-20160904t092233-20160904t092333-012901-014632-001_filter

s1a-ew-grd-vh-20160904t092233-20160904t092333-012901-014632-002_filter

s1a-ew-grd-vv-20160904t092233-20160904t092333-012901-014632-001_winddir

s1a-ew-grd-vh-20160904t092233-20160904t092333-012901-014632-002_winddir