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StatusCompleted
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Status date2015-03-27
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Activity Code1A.089
The objective of the Gloria (GLobal Reach for Internet for All) study is to assess how multi-layered systems (GEO, LEO, MEO and HAPS (High Altitude Platform Systems)) may be used to fulfil a set of telecommunication missions, from low rate data collection to broadband internet access.
We showed through the analysis of the needs, the definition of the reference scenarios and the assessment of the perceived gaps that no existing GEO or MEO solution could address all the needs. A workshop with different brainstorming sessions was organized to identify possible multi-layer architectures.
A multilayer solution composed of a GEO, a LEO and a HAPS layer was defined and a first dimensioning of the LEO layer was made, leading to a quasi-polar constellation of 170 satellites. Performance and utilization of the HAPS in different part of the system have been assessed, in particular on the user side and the gateway side.
A system simulator was built to evaluate the performance under various conditions (rain, position of the user, type of service, etc…) and assess Key Performance Indicators of the system (coverage, throughput, BER, delay, etc…).
One of the major challenges of the GLORIA multi-layer system is to cope with a large range of services and address simultaneously the high end and the low end market. For this, the role of the different layers GEO, LEO and HAPS had to be defined in a complementary way.
Another challenge of the GLORIA is the strong delay constraints of some internet applications and the high capacity requirements to offer internet for all services.
The benefits of the GLORIA multi-layered system are multiple. The GLORIA system provides a flexible and optimised internet for all access solution :
- global medium capacity layer from Geostationay orbit
- worldwide coverage, including over polar areas from the LEO constellation
- high capacity on hot spot from the HAPS layer
The GLORIA system optimizes also the end to end delay for delay sensitive applications as well as the minimum elevation versus GEO only solutions.
The utilisation of the HAPS as optical feeder termination enables to increase the throughput of space solutions.
The GLORIA multi-layered system offers a worldwide internet access from terrestrial like terminals with data rates up to 384 kbps (4 Mbps with directive terminals) and reduced latency versus GEO only solutions
The system simulator enables to choose the location of the user and assess the performance of each layer separately. It supports the following features :
- Automatic scenario creation
- Dedicated GUI
- Dedicated Processing (handover) and reporting (access, link budget)
The GLORIA multilayer architecture is composed of three different layers :
- a GEO layer composed of 3 satellites located around the GEO arc. It provides a global coverage in S Band and a regional coverage in Ka band. The service grade is 64 kbps with omni directional terminals and up to 4 Mbps with directive terminals.
- a LEO layer composed of a constellation of 170 quasi-polar satellites (81.3°) on 10 planes at 1560 km of altitude in S Band. The constellation provides a worldwide coverage at 64 kbps with reduced latency.
- a HAPS layer providing enhanced service rates on hot spots with terrestrial terminals
The GEO and LEO satellites are equipped with multibeam beam antenna and large reflectors to enable the closure of the link budget with terrestrial like terminals. The selection of the best layer depends on the requested service grade, on the terminal capability and on the coverage of the different layers. The use of IMT2000 frequencies and a single W-CDMA technology in S Band has been chosen to facilitate
the development of low cost multi-mode terminals (GEO+LEO+HAPS). Ka Band has been reserved for the broadband internet access with directive terminals.
The study was executed in 24 month and articulated around three main phases :
- a first phase to refine the needs, define scenarii and evaluate the gaps between the current offer and the needs. The first phase ended with the Need and Gaps Review.
- a second phase to review the technological state of the art, identify possible architecture and trade-off between the solutions. The second phase ended with the Preferred Solution Selection Review.
- a third phase to model the system and assess the performance of the preferred solution. The third phase ended with the Solution Evalution Review.
The study is closed.
