Patent ID: 8436725

Claim:
A tracking system which comprises: at least one positioning device ( 2 ); at least one localizer ( 1 ); the at least one positioning device employs a plurality of different positioning systems and in case the at least positioning device detects that the positioning system which is being used is inoperative, it will switch to another positioning system that is operative; the at least one localizer is a mobile unit; the at least one positioning device including a plurality of different communication interfaces; the at least one localizer including a plurality of different communication interfaces; the at least one localizer and the at least one positioning device configured to communicate between each other either in a direct form through a radio-link or one or more multi-purpose network infrastructures, and in an indirect form through a network of dynamic or changing topology formed by node localizers, and in a hybrid form using one or more forms of communication, among direct, indirect and deferred mode wherein this deferred mode uses an intermediate centre ( 3 ) which monitors, stores and forwards the messages; wherein if the at least one localizer or the at least one positioning device detects that the communication interface which is being used is inoperative, it will switch to another communication interface that is operative in order to establish communication; wherein the selection of the communication interface is governed by a system of priorities which depend on environmental parameters; the at least one localizer and the at least one positioning device incorporating functions for establishing themselves as network nodes ( 4 ); the at least one positioning device configured to communicate with several localizers simultaneously; and the at least one localizer device configured to communicate with several positioning devices simultaneously.