SAET railway TLC system is devised with the objective of providing passengers of high-speed trains with two main typologies of service:
- Broadcast digital TV.
The network infrastructure shall consist of an access portion and a fixed terrestrial portion, as shown in the following figure.
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The access portion is based on a satellite system. This system is characterised by a geostationary satellite operating at Ku band and providing the support for broadband communications. Transparent payloads, available in commercial satellites, have been considered for the architecture baseline. In the areas where the satellite radio channel is unavailable due to fading effects, the satellite system will be integrated with suitable gap filler systems in charge of extending the satellite connectivity.
The fixed terrestrial portion is composed by a federation of service and content providers:
- The railway operator will act as a service provider by directly providing multimedia services to passengers,
- Third-party service and content providers will provide additional multimedia services
- TV broadcasters.
A satellite positioning system will be included in the system to provide the positioning information necessary (i) for location-based services, (ii) for the pointing, acquisition and tracking (PAT) algorithm of the train mobile satellite terminal antenna, (iii) to assist mobility procedures. Either EGNOS/Galileo or GPS may be used as satellite positioning system.
By means of the above listed access network systems (outdoor links) a train can connect the fixed terrestrial portion. Towards this end, an in-train sub-system will be installed in each train. The characteristics of the access n