undef

s1a-iw-grd-vh-20171114t205119-20171114t205144-019266-020a2d-002_filter

s1a-iw-grd-vv-20171114t205119-20171114t205144-019266-020a2d-001_filter

s1a-iw-grd-vh-20171114t205119-20171114t205144-019266-020a2d-002_winddir

s1a-iw-grd-vv-20171114t205119-20171114t205144-019266-020a2d-001_winddir