The objectives of “The role of Satellite in converged mobile/fixed/broadcasting environments” are to investigate:
Breaking this up into further details, the following general issues are to be treated in the study:
The study aims to answer the following two central questions:
“Scenario definition” is the second phase of WP2000. Based on the topics found useful in Phase 1 of this WP, the relevant integration scenarios (including the associated service offerings) will be specified and analysed (using only a top-level view on the (air) interfaces). This analysis will contain a critical as to what extra benefit is obtained by the satellite in these scenarios (i.e. whether the use of the satellite on top of a terrestrial LTE appears commercially sensible).
Also, in the 4th phase of WP3000, referred to as “Architecture comparison,” different proposed solutions will be compared. This includes discussion of potential gains over existing systems in terms of feasibility and cost-benefit-analysis of deployment, service availability/coverage, resource usage, and additional service offerings. Following this, most promising solution(s) for each approach based on the outcome of the comparison will be identified. These solutions will be then kept as reference architectures for the remainder of the study.
For integration purposes, two major scenarios exist:
S1: Usage of satellite for backhauling in an LTE network:
Scenario S1 can offer an advantage over a terrestrial-only backhaul network, if the connection via other carriers (e.g., directional microwave transmission, cable, fibre) is either more costly or impractical due to other reasons. Especially directional microwave transmission is used very often in cellular networks. Hence, a satellite for backhaul could only be interesting for very remote cells. Another motivation for satellite backhaul are moving (femto-)cells, like LTE eNBs in trains, planes or coaches, which currently do not fit into a conventional terrestrial LTE(-A) infrastructure. Payload from such cells could be backhauled by a satellite much more easily than using a terrestrial connection.
One example of S1
S2: Usage of satellite for direct reception and transmission by the User Equipment:
Here, one of the potentially largest advantages for the integration of the satellite is that it offers additional frequency bands to be used by the mobile users:
Proposed converged application layer architecture
The architecture definition of a converged application layer assuming hybrid lower layer network interfaces to 3GPP LTE, as well as to DVB satellite systems, such as DVB-S2, -SH or the emerging -NGH is an important and central task of this study. Convergence between satellite and cellular network systems will inherently depend on the ability of a system to control data and media flows over the different access technologies.
As depicted in the figure, the system stack of a converged multimedia delivery system with underlying LTE/SAT access technologies is depicted.
System stack of a converged LTE/SAT system
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The project is organized in 5 main Work Packages.