The company Sensis Corporation , acquired in August 2011 by Saab AB, has set up at Roissy CDG airport a mode S multilateration system. The configuration of this system requires the reading of the antennas in WGS84 coordinates and a precision control ( metric) of determined positions.
This control is done by equipping a vehicle with a transponder and a GPS to simulate the route of airplanes on runways, taxiways and parking lots. This circuit is covered by permanent radio link with the control tower, day or night depending on the airport. A comparison of the two readings is then made using analysis software.
An article describing this service in detail has appeared in XYZ (journal of the French Association of Topography ).
We carried out these operations at nearly fifteen major international airports, spread between Europe and Asia.