{"type": "FeatureCollection", "_meta": {"__meta__": "synthetic", "disclaimer": "Synthetic demo data inspired by real Baltic geography, MMSI/OUI conventions, and infrastructure. Not real observations.", "dataset": "s4-spoofed-ais-identity/area_of_interest", "version": "1.0"}, "features": [{"type": "Feature", "properties": {"featureId": "s4-aoi", "name": "S4 Area of Interest", "note": "Hanko -> central GoF -> Helsinki, covering T\u00c4HTI loop, spoof tracks and SILAKKA decoy."}, "geometry": {"type": "Polygon", "coordinates": [[[22.5, 59.55], [25.5, 59.55], [25.5, 60.3], [22.5, 60.3], [22.5, 59.55]]]}}]}