Dynamic AIS™ is an innovation from Spire Maritime that taps on thousands of satellite-enabled AIS receivers traveling through the busiest shipping lanes in the world.

Spire has a large number of small satellites working in radio frequencies, which allows the company to clean up muddy signals; the same can’t be said of looking at ships visually. The company will in fact layer three types of AIS to provide the best possible accuracy in tracking ships around the world: terrestrial (or harbor) receivers, satellite receivers, and what it calls “dynamic” AIS. That means more detection systems on surface that communicate with the satellites in their assigned orbit, in areas of highest demand. (Meaning, the high traffic areas you might be sitting in while going in and out of port on a cruise ship.)

Read more here:

https://www.forbes.com/sites/elizabethhowell1/2020/01/13/hiding-in-high-ship-traffic-how-one-us-company-tracks-vessels-at-busiest-times