SURVEILLANCE SYSTEM FOR TERRESTRIAL NAVIGATIONAL AND AIRPORTLANDING SYSTEMS

摘要

The invention deals with a surveillance system for terrestrial navigational and landing systems, in which the navigational signals being transmitted for aeroplanes or other airborne objects by the navigation al and airport landing systems are received and evaluated by a ground-based receiving and control facility. In this system: the receiving and control facility is equipped with a plurality of additional receiving stations; these additional receiving stations operate in the frequency range of the navigational signals; the additional receiving stations are arranged geographically distributed within the transmitting ran ge of the navigational or airport landing system; the signals recorded by the additional receiving stations are forwarded to a central evaluating unit.