DATA COMMUNICATION SYSTEM, RAILWAY SYSTEM COMPRISING SUCH A COMMUNICATION SYSTEM AND RELATED COMMUNICATION METHOD

The data communication system (16) according to the invention comprises: - a first transceiver module (30) for transmitting data in the form of a radio signal, - a first radio antenna (32), connected to the first module (30) and positioned near an electric conductor (20), the first antenna (32) being configured to transmit, respectively to receive, the radio signal in the form of surface radio waves propagating along the electric conductor (20), - a second radio antenna (34), and - a second data transceiver module (36), connected to the second antenna (34) and configured for exchanging data with the first transceiver module (30). The second antenna (34) is positioned away from the electric conductor (20), and is configured to receive waves radiated from said electric conductor (20), respectively to transmit radio waves, some being designed to propagate along the electric conductor (20) in the form of surface waves.