PAGE CONTENTS
Objectives
- Use a more efficient satellite technology permitting the use of the Adaptive Coding and Modulation (ACM) in both the forward link and the return link for a better space segment efficiency
- Improve reacquisition time of the satellite system (modem) after long shadow zones
- Develop a more robust TCP and HTTP acceleration system to be able to handle satellite link with high end-to-end delays adapted to cope with the type of traffic used by the train users
- Better QoS implementation in order to discriminate different typologies of traffic;
- Aggregate links of different nature (e.g. terrestrial and satellite) with different end-to-end delays in order to make them acting as one aggregated link
Challenges
- Making ACM work in both Forward and Return link in a mobile environment with frequent obstacles
- Cellular and satellite link are different, it will be a challenge to make them work together with generic components sourced from third parties
- Organising a pilot on a commercial train.
Plan
The project is divided in three main stages:
- First stage: development and static test in the lab
- Second stage: testing in mobile environment complemented with development and test in lab
- Third stage: going live for a Pilot of 1 month on a commercial train
All the main activities are conducted by 21Net.
Current Status
The CDR meeting has been successfully carried out in June 2014, which marked the completion of trade-off and design activities.
In the process of the design, opportunities for additional developments have been identified, which would respond to the performance limitations encountered in the configuration selected in the original architecture.
The new satellite solution is looking promising, and substantial improvements with respect to the previous solution are expected.
Acceptance tests of the system are expected to take place in July 2014.
Companies
21Net Ltd
United Kingdom