undef

s1a-ew-grd-vv-20180820t091300-20180820t091400-023328-02898a-001_filter

s1a-ew-grd-vh-20180820t091300-20180820t091400-023328-02898a-002_filter

s1a-ew-grd-vv-20180820t091300-20180820t091400-023328-02898a-001_winddir

s1a-ew-grd-vh-20180820t091300-20180820t091400-023328-02898a-002_winddir