The implementation of the concept of creating personal communication networks provides for the provision of a wide class of services under the motto “anywhere, anytime” using a single personal subscriber number. The work is carried out on the basis of global integration of existing and emerging networks of fixed, terrestrial mobile and satellite communications, the creation of special terminals that ensure interconnection of communication standards and protocols. As part of this integration, a satellite phone has a special position, because it provides a global coverage area.
Space connection
In the understanding of most people, satellite communications is something exotic from a series of films about James Bond. In fact, millions of people on the planet have a mobile satellite phone and need to be in touch 24 hours a day, 365 days a year anywhere in the world. As a rule, the subscribers of dozens of companies providing space communications are businessmen, senior officials of large companies, government agencies, geologists, researchers, travelers, less commonly ordinary people living in remote areas.
Personal Satellite Communication Systems (SPSS)
Since 1985, the International Telecommunication Union has been developing the concept of globalization and at the same time personalizing communications on a global scale. 10 years later, a landmark world conference was held in Buenos Aires, at which the scope and parameters of the global information infrastructure were approved. It consists of a single interconnected system "personal telephone - satellite communications - land communications".
In addressing the problems of globalization and personalization of communications, MSS systems represent the only economically viable solution to communications that reach hard-to-reach, remote and sparsely populated regions of the planet.
The main objectives of the project
- Globalization of communication - the provision of communication services regardless of the location of the user.
- Personalization of communication - bringing services to end users who want to receive services.
- Personal terminal (satellite phone, data transmission devices) - users have means of communication with a personal number.
- Public services for personal users.
- Private service - for certain groups of users.
Classification of communication systems
Distinguish between high-speed and low-speed communication systems.
- Low-speed : Iridium, Globalstar, ICO, Odyssey, Signal, ECCO, Rostele-Sat, Ellipse, Archimedes, Polar Star and others. The range of services: telephony, fax, data transfer. At the moment, also implemented high-speed transmission of information. For example, the modern Iridium satellite telephone provides both stable, secure voice and network communications.
- High-speed : Celestri, Spaceway, Skybridge, Teledesic, Secoms and others. They specialize in global interaction services, such as high-speed Internet access, remote user access to databases, high-quality video telephony and conference calling, multimedia services based on various modifications of communication terminals, including basic ones targeted at a wide range of personal users.
Iridium Project
Back in 1987, long before the ITU World Conference, Motorola conceived an ambitious global communications project, available around the clock around the world. The project was called Iridium. Initially, it was planned to put 77 spacecraft (SC) into low orbits, but after recalculations the number of satellites was reduced to 66.
To carry out work on the project in 1993, the international consortium Iridium Inc (Washington) was created. The composition of the rights of investors included companies: Motorola, Lockheed Martin, Nippon, Raytheon, Sprint Corp. and a dozen other representatives. From the Russian side, the investor (82 million dollars, 5% of the shares) was the leading rocket and space company of Russia GKNPC them. Khrunicheva. She, under a contract with Motorola, launched the Iridium spacecraft with the help of PH Proton. The first call through a satellite phone was made in the summer of 1997.
Crash and rebirth
The main constellation of satellites was launched in 1997-98, and commercial operation is considered to be September 23, 1998. However, the greed (unreasonably high tariffs) of managers a year later led to the bankruptcy of the project. The Motorola company faced the issue of withdrawing satellites from orbits, which required $ 40 million.
Fortunately, there were investors who believed in the effectiveness of the project. Created in 2000, Iridium Satellite LLC bought assets for 25 million, and, having secured orders from the US Department of Defense, resumed commercial operation of global satellite systems. In 2009, another reorganization was required - Iridium Communications Inc. became the end user
Current state
Now Iridium is a quite successful project with a subscriber base exceeding half a million customers. Among them are the most influential figures of the planet, heads of the largest companies, government services of different countries, workers of transport, construction, mining companies, emergency services and other categories. In principle, Iridium satellite phone with a range of services can be purchased by anyone.
Equipment
Iridium Communications itself produces most of the equipment for high-speed data and voice communications. For customers, both “inexpensive” and flagship satellite phones are available in a rugged case. The most popular are the Iridium 9505A, 9555 and Extreme (9575) models. Internet access is provided by 9522A, 9522B and 9602 modems, and automatic data exchange of the M2M class is provided by Iridium 9601 and 9602 devices.
To save energy, the devices are equipped with monochrome displays. Phones have a high degree of protection against shock, moisture, dust, temperature extremes. The most recent model is the Iridium Extreme satellite phone (9575). This is a fairly portable device compared to its predecessors and competitors. The phone works anywhere in the world and provides the most reliable voice, data and GPS positioning. The Iridium 9575 combines the functions of the Iridium 9555 satellite phone and the Shout Nano satellite GPS tracker. The model has the following features:
- Protection against dirt, vibration, shock, water (IP65, MIL-STD 810F).
- Built-in GPS
- Programmable SOS Button.
- Built-in radio beacon that helps you search the sea.
Types of services
Iridium system provides subscribers with the following types of services:
- Voice communication. The speech encoder uses a vector-sum excited linear prediction (VSELP) linear prediction algorithm. Speech transfer rate - 2.4 kbps. The duration of the negotiations is 30 seconds. (without interruption of communication) will be provided with a probability of 98%.
- Data transfer. A transparent transmission with a variable message length is performed. It is also possible to transmit short messages that determine the location and status of the subscriber.
- Fax messages . The terminal is capable of receiving and storing messages in memory; their subscriber can view them by scrolling the message on the display screen.
- Personal call.
- Location determination.
Project Turaiya
Unlike the Iridium global network, Thuraya is a regional project operating mainly in Europe. While Motorola and partners launched 66 spacecraft, the European project is content with three suspended in geostationary orbits. However, a satellite phone connected to the Thuraya system (from Arabic - the Pleiades constellation) will also be able to receive / send calls in Australia, Africa, and Central Asia. A separate brand, ThurayaDSL, has been created to make Internet connections.
Statistics
A company registered in the UAE conducts a profitable business. It has a subscriber base approaching 300,000 customers, revenues in 2006 alone exceeded $ 80 million. For comparison: the company ended 2005 with a positive balance of $ 26 million.
Equipment
If we compare the Iridium and Turaiya equipment, for example, satellite phones, the photos clearly show their external and functional differences. Many Thuraya devices are equipped with compact (retractable) antennas, while the signal level is more than stable in the area covered by satellites (this is noted in user reviews).
Outwardly, the Turaiya satellite phone resembles the “handsets” of the mid-2000s mobile communications: the case dimensions are small compared to competitors, the color screen, and more or less modern design. Moreover, the devices have the necessary degree of protection. But, most importantly, the devices are equipped with a GSM module, that is, in the area of cellular communication, if there are service providers with whom the Arab company has concluded an agreement, the phone works like a regular cell phone. In the absence of a GSM connection, it automatically connects to satellites.
The user functionality of the devices is the same as that of conventional mobile phones: a convenient user menu, Java games and applications, data transfer, a USB interface. Of the "adult" functions - an advanced GPS-system.
Satellite Phone Thuraya XT
This is the flagship of the company "Turaiya", which became the first among analogues with enhanced protection against dust, harmful substances and moisture, class IP54 / IK03. The shockproof housing made of polycarbonate materials, as noted in the reviews, withstands severe falls and vibration. Additional resistance to aggressive environments is provided by rubber gaskets and aluminum spraying.
Specifications:
- The 262000K color display measures 2 inches and has a resolution of 176x220 pixels.
- Fax and data transmission is possible both via dial-up channel (low speed, about 9.6 kbps) and GmPRS (output - 15 kbps, reception - up to 60 kbps).
- Determination of GPS coordinates with saving of ten last indications.
- USB, standard headphone jack (3.5 mm), light sensor.
- SAT frequencies: “sky / earth” - 1525/1559 MHz, “earth / sky” - 1626.5 / 1660.5 MHz.
- Dimensions (width / height / thickness): 53/128 / 26.5 mm. Weight - 193 g.
Services
- Voice and SMS via satellite phones.
- Fax and Internet through telephones.
- ThurayaIP allows you to transfer data at a speed of 444 kbit / s to a special terminal.
- Determination of GPS coordinates.
- Emergency help call .
- Voicemail, WAP, missed calls, call waiting, call back, news and other services.
Conclusion
The Iridium and Turaiya companies, while seemingly providing the same satellite communications services, have a completely different concept and scope of activity. If an impressive grouping of satellites is involved for the North American project, then three partners operating in geostationary orbits are enough for Arab partners. The undoubted advantage of Iridium is uninterrupted communication throughout the Earth, and the trump card of Thuraya is more modern and convenient phones that can work in GSM networks.