undef

s1b-ew-grd-hh-20170525t144130-20170525t144234-005756-00a15d-001_filter

s1b-ew-grd-hv-20170525t144130-20170525t144234-005756-00a15d-002_filter

s1b-ew-grd-hv-20170525t144130-20170525t144234-005756-00a15d-002_winddir

s1b-ew-grd-hh-20170525t144130-20170525t144234-005756-00a15d-001_winddir