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System Architecture
A Superior Mobile Satellite System
Thuraya-1 satellite was launched on 21st October 2000; on board a Sea Launch Zenit-3SL rocket from the equator in the middle of the Pacific Ocean .It was the heaviest commercial payload ever launched and the first commercial satellite to employ digital beam forming. Thuraya's commercial services have begun in a gradual roll out in a number of countries in 2001.
The Thuraya mobile satellite system is a turnkey project built by Boeing Satellite Systems, formerly Hughes Space and Communications International, Inc. (HSCI), at the cost of US$ 1 billion. Designed for a lifespan of 12 to 15 years, Thuraya’s satellite will maintain geo- synchronous orbit at 44° East. The contract includes manufacture of two high power geo- synchronous satellites, the launch of the first satellite, manufacture and installation of the ground network equipment, the manufacture of nearly a quarter of a million mobile handsets and the project insurance.
Thuraya’s system has been adapted for efficient operation in both satellite and GSM environments. It provides high flexibility in managing network resources through a re- programmable satellite payload. This supports modifications to the system’s coverage area even in the post-launch period and optimises performance over high demand areas.
Thuraya’s satellites have been specially designed to achieve network capacity of about 13, telephone channels. Thuraya’s hand held mobile terminals are comparable to GSM handsets in terms of size and appearance, as well as in voice quality.
Satellite features
250-300 spot beams
Digital beam forming (which provides for dynamic area coverage and optimises over change in traffic demand)
Single hop link for mobile-to-mobile communications
High power capacity
Dynamic satellite power control providing 10dB link margins
The Thuraya system is comprised of three key elements - Space Segment, Ground Segment and User Segment.
Service Features
Voice telephony Fax Data Short Messaging Location Determination Emergency Services High Power Alerting
Regulatory Data
Frequencies:
Mobile Links Earth-to-space 1626.5-1660.5 MHz Space-to-Earth 1525.0-1559.0 MHz
Feeder Links Earth-to-space 6425.0-6725.0 MHz Space-to-Earth 3400.0-3625.0 MHz
Space Segment
The Space Segment comprises one operational satellite in geo-synchronous orbit, located 36, kms above the equator with one spare satellite ready for deployment. The first operational satellite was successfully launched on the 21st October 2000 and full commercial service have begun in a gradual roll out starting from April 2001 in many countries in Thuraya's coverage area. The Thuraya Geo satellite, which constitutes the Space Segment, is operated and managed by a sophisticated and integrated ground network known as the Ground Segment. The Ground Segment includes the Satellite Operation Centre, which monitors and controls satellite movement, ensuring the overall and ongoing maintenance of satellites in geo-synchronous orbit. Satellite Overall Design
- Number of satellites: 2
- Type of orbit: Geo-synchronous orbit with 6° inclination
- Orbital locations: 44° E and 28.5° E
- Service life of 12 years
- Compatible with Sea Launch and Ariane 5 launch vehicles and others
- Supplier: Hughes Space & Communications International, Inc.
Payload Subsystem
- 12.25 meter aperture deployable satellite antenna
- On-board digital signal processing (DSP) to facilitate interconnectivity between the common feeder link coverage and the spot beams to make effective use of the feeder link band and to facilitate mobile to mobile links between any spot beams
- Digital beam-forming capability which allows Thuraya to reconfigure beams in the coverage area, to enlarge beams and to activate new beams. It also allows the system to maximise coverage of "hot spots", or those areas where excess capacity is required.
- The flexibility to allocate 20% of the total power to any spot beam.
- The flexibility to reuse the spectrum up to 30 times and therefore use the spectrum efficiently.
- The signal characteristics of 8 time-multiplexed voice circuits: Modulation pi/4 QPSK FDMA carrier channel BW 27.7 kHz Channel bit rate is 46.8kbps
User Segment
- 13,750 Satellite Traffic Channels
- One Primary Gateway (PGW)
- Regional Gateways (RGW)
Thuraya Services
Thuraya's wide range of services including voice, data, facsimile, messaging and location determination enhance service options for subscribers already served through land-based operators, while opening up new opportunities for those living outside these networks
Teleservices
- Voice telephony
- Emergency services
- Group 3 fax
- SMS beam broadcast
Bearer Services
- Asynchronous Data Services (9.6 kbps)
- Packet Assembly / Disassembly (PAD) Services (9.6 kbps)
Supplementary Services
- Call forwarding
- Call waiting
- Call hold
- Call transfer
- Advice of charge
- Calling Line Identification Presentation (CLIP)
- Conference calling
Value Added Services
- Short Message Service (SMS)
- Voice mail
- Operator assisted services
- Subscriber Location Determination
- Interactive Voice Response (IVR) Services
- Prepaid Services
- Freephone and Premium rate
- Hot billing
Services
- Voice- comparable to GSM quality.
- Data- in 9.6 kbps.
- Facsimile- ITU-T G3, also in 9.6 kbps.
- Messaging- GSM short messaging.
- Location Determination- also known as Global Positioning System or GPS. Accuracy within 100m.
"Satellite + GSM + GPS"
Thuraya's mobile phones integrate satellite , cellular (GSM) and location determination (GPS)- three distinct and powerful technologies in a single handset
The integration of satellite and GSM ensures that the user can connect to local terrestrial networks while automatically switching to satellite mode outside those systems. For the user, this translates into seamless and uninterrupted mobile phone service. For the service provider, it means that alliance with Thuraya translates into the dynamic expansion of their terrestrial networks, and the ability for them to generate revenues from beyond their systems.
Thuraya offers quality dual-mode terminals that offer satellite and GSM connectivity. This flexibility ensures continuous and cost-effective roaming for users. Essentially, Thuraya subscribers would continue using their national land-based mobile network, but will be able to automatically switch to Thuraya satellite mode in areas that are outside the terrestrial system.
Another advantage is that outside Thuraya’s coverage area, subscribers would still have the convenience of roaming in other GSM networks areas. This combination of advanced and flexible system designs ensures reliable, global mobile services to subscribers.
Satellite+GSM+GPS
Satellite Thuraya’s satellite service enables you to make and receive calls from anywhere in 99 countries over three continents, and in places that are not covered by local terrestrial telecom network.
If you wish to call some person, and you are out of the local network, your satellite call will be sent up in space to Thuraya’s satellite, then relayed to the Thuraya primary gateway, which will check the subscriber’s details and authorize the call connection.
GSM
Thuraya provides a satellite telecommunications platform based on GSM which enables the Thuraya system to support roaming as defined by GSM and necessitates the establishment of roaming links with all GSM operators worldwide. This coordination allows GSM subscribers to use the Thuraya network whenever they roam into Thuraya footprints, and give Thuraya direct customers access to use other GSM networks.
With Thuraya’s roaming capabilities, GSM subscribers will no longer suffer from ‘No Service’ whenever their home GSM operator service fails because they will switch automatically and be able to roam on Thuraya’s network.
Thuraya to offer WAP! Thuraya will soon offer Wireless Application Protocol in its mobile satellite phone. More
Thuraya to Offer Display Additional Languages Focusing on the needs of the regional Thuraya users, Thuraya will soon introduce additional Mobile Micro Interface (MMI) languages in its satellite mobile phone. The MMI languages feature enables the Thuraya user to customise the phones to display the language of their preference on the micro browser. Thuraya users will be able to switch their phone to additional languages such as Turkish, Arabic, Farsi, Urdu, Russian, and Hindi
