Flexible software-based radios
At the heart of every RETB in-cab signalling system is the radio network.
The RETB network operates as a chain of base stations. When a call is placed either by a train or the signaller, it is relayed along the chain and rebroadcast at every coverage cell.
This means that every user on the network hears every call, no matter what channel they are tuned to. Using GPS timing and cell announcements, train radios automatically tune to the strongest channel. This reduces the driver’s work load and maintains good quality radio coverage for both voice calls and token transactions.
RETB base stations are built from easily configurable modular blocks. Operating on the VHF band, the radio network can cover large areas with only a few fixed sites.
Each radio site can have a different configuration of modular radios, depending on the requirements of the network. This modular construction and quick-change design allows faults to be quickly remedied.
The RETB fixed site radios at Inverness Signalling Centre in the UK