undef

s1a-iw-grd-vv-20170910t101715-20170910t101744-018312-01ecd9-001_filter

s1a-iw-grd-vh-20170910t101715-20170910t101744-018312-01ecd9-002_filter

s1a-iw-grd-vv-20170910t101715-20170910t101744-018312-01ecd9-001_winddir

s1a-iw-grd-vh-20170910t101715-20170910t101744-018312-01ecd9-002_winddir