Study on feasibility of SATCOM for railway communication

Final Report
Speed
Type (voice/data)
20
15
10
5
CA
PA
BA
CSA
15
10
5
0
CA
PA
BA
CSA
0
Low Normal High
PSA
PSA
Symmetry Up/Down
Distribution
25
20
15
10
5
CA
PA
BA
CSA
30
25
20
15
10
5
0
CA
PA
BA
CSA
0
50/50 100/0 80/20 N/A
PSA
PSA
Figure 10: Railway applications for the FRMCS - communication attributes: Speed, Type, Symmetry
and Distribution – System features
The main conclusions obtained from the data compiled for the critical application mentioned in the
URS document are that:
High reliability is required for these critical applications (in comparison to the performance
and business ones).
Low latency and immediate setup are highly demanded in most of the critical applications.
Voice calls shall be supported, including user-to-user and multi-user.
Narrow 6 band systems seem to be sufficient to support voice and data in critical applications.
6
New future railway critical applications are being considered nowadays and could change this conclusion about narrow band systems
and their ability to support the complete set of voice/data critical apps. For example, the transmission of a real-time video for ATO
purposes is being discussed at present. If this application (or a similar one) is finally confirmed, this assumption will not be true.
However, it is interesting to point out that in other fields (such as the RPAS – Remotely Piloted Aircraft System) similar discussions have
been addressed, and finally video applications have been discarded. In fact, video image processing is expected to be eventually
performed on-board (thus avoiding the transmission of large amount of data through the return channel).
Doc.Nº: SRAIL-FNR-010-IND
Edit./Rev.: 1/1
Date: 16/02/2017
Page 44 of 285