Transponder landing system

TLS electronics shelter, elevation sensor and uplink antennas – Santa Cruz Air Force Base, Rio de Janeiro, Brazil, August 2009
TLS at Teniente Rodolfo Marsh Martin Aerodrome November 2010, Base Presidente Eduardo Frei Montalva Antarctica

A transponder landing system (TLS) is an all-weather, precision landing system that uses existing airborne transponder and instrument landing system (ILS) equipment to create a precision approach at a location where an ILS would normally not be available.