[throw0101c]

> Was curious if ground vehicles at airports also use transponders to communicate position […]

They do at CYYZ (Toronto Pearson):

* https://www.flightradar24.com/43.68,-79.63/13 (zoomed in)

* https://www.flightradar24.com/airport/yyz

Also at CYUL (Montreal Trudeau) and CYVR (Vancouver International).