JPDA gating notes
- gate on Mahalanobis dist, chi2 thresh @ 0.99 for 2D
- AIS-to-radar assoc: gate on position AND course/speed, MMSI is a hint not a key
- emitter (KINGFISHER) to kinematic track: associate by bearing-rate match over time
- watch for track coalescence in close formation -> bump process noise or split
TODO: spoofed-AIS detector. corroborate vs radar; flag MMSI w/ no radar return.