The SDM (Synchronous Data Manager) application optimises data transmission over the air interface from the on-board equipment to the Control Centre. The application is based on standard TETRA service SDS and consists of a smart polling of the whole fleet of terminals (vehicles/trains and others).
In the transport sector, this application is usually used for the transmission of:
- Operational vehicle information
- Status of on-board subsystems
- Position information
This application guarantees an efficient use of TETRA control channels (MCCH/SCCH) so that voice and data services coexist simultaneously and the quality of them is not undermined.