Study on feasibility of SATCOM for railway communication

Final Report
Inmarsat 5 (Global Xpress)
Criterion ID Criterion Evaluation Justification
CRT-TECH-11
The proposed satcom system shall support as minimum Low
bandwidth applications
C (High)
With the use of Ka-band, Inmarsat 5 (GX) supports broadband applications. It
means that critical railway applications are supported. But also some other such
as performance and/or business applications can be provided by Global Xpress.
CRT-TECH-12
The proposed satcom system for the FRMCS shall provide
“user-to-user” and “multi-user” types of communications for
both voice and data services. In addition, each communication
can be bi-directional or uni-directional with any type of
asymmetry between forward and return channels (when bidirectional).
NC
In general, the user to multi-user communication on the return link (i.e. from the
remote terminal point of view) is not a service offered by satcom solutions.
In this case, and despite it is an all-IP solution and it could be implemented at IP
level, Global Xpress is a "closed" system that does not provide this service and
required modifications depends on the satcom service provider (i.e. Inmarsat).
CRT-TECH-13
The minimum required coverage of the satcom system shall be
Europe.
C
Inmarsat 5 (GX), with its 3 current satellites (4 in a near future), provides coverage
worldwide (excluding poles).
CRT-TECH-14
The satcom system shall provide communications for remote
terminals when stationary and when travelling at speeds up to
the maximum allowable line speed or 500 km/h, whichever is
the lower.
C
GX air interface is based on standards DVB-S2 and RCS2. Mobility extensions
have also been considered to support high-speed environments since it provides
service to airplanes, as well.
CRT-TECH-15
The proposed satcom system shall be flexible to support (at
least) new created apps in the future.
C (High)
DVB-S2/RCS2 standards have been designed to provide high level of flexibility
with lots of modcods and bandwidth channelization. Since Global Xpress is based
on these standards, it can be considered highly flexible.
CRT-TECH-16
The proposed satcom system shall be highly and easily
scalable.
C (Low)
The use of the Ka-band provides high level of scalability. In addition, Global
Xpress provides additional techniques such as multi-beam and frequency reuse
that increase scalability.
Doc.Nº: SRAIL-FNR-010-IND
Edit./Rev.: 1/1
Date: 16/02/2017
Page 280 of 285