undef

s1b-ew-grd-hv-20171217t160613-20171217t160713-008761-00f973-002_filter

s1b-ew-grd-hh-20171217t160613-20171217t160713-008761-00f973-001_filter

s1b-ew-grd-hv-20171217t160613-20171217t160713-008761-00f973-002_winddir

s1b-ew-grd-hh-20171217t160613-20171217t160713-008761-00f973-001_winddir