Vehicle movement area transmitters (Vmats) have been installed at both Denver (DEN) and St. Louis-Lambert (STL) international airports to help improve runway safety.

Vmats permit ground vehicles operating on the airport surface to broadcast their positions and uniquely identifiable callsigns receivable by local ADS-B systems. Air traffic controllers can then view and track vehicles, as well as appropriately equipped aircraft, operating near the airport and on the airport surface via ground radar systems installed in tower cabs. This enhanced situational awareness for air traffic controllers and pilots provides a complete picture of airport surface activities for greater safety and efficiency.

Forty Vmat devices are currently operational at STL, and 55 Vmat devices will soon be operational at DEN.