SMART BEACON

Smart beaconing, as compared to fixed time interval, increase the effectiveness of both the RF spectrum and detail plotting on the map. Smart beaconing combines change of course (heading) with speed and thus also induces a randomness to the packet transmit time.

A lot more information is available at this website

The below picture shows some tracks are diagonal across intersections (corners) and is thus not s smart beacon, while another defines the block by beaconing on heading/course change.