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How Satellite Phone works? |
Satellite Phone - How does it work?
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Satellite
Phone Handhelds
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Satellite Phone - Basic Concept |
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How It Works
Topics (Click link to jump down)
Overview of a Globalstar Phone Call
- A caller uses Globalstar mode to place a call via the satellite to one or more Gateways
- The Gateway routes the call to the existing phone network, in the case indicated below, a cellular Public Land Mobile Network (PLMN) network
- The PLMN routes the call to the intended receiver. The call is completed!
- The call duration, service used, and service area are reported to the Service Provider for billing.
Making a Call via Satellite vs. Cellular
- A subscriber in Russia is
calling her friend in San Francisco on her Globalstar satellite
phone. Her signal is handled by a passing satellite.
- The satellite relays the call to
a Gateway in its footprint.
- The Gateway converts the signal
to work with the local PSTN and passes on the call. Depending on
the distance between the callers, a Globalstar satellite call
might pass through several Gateways and PSTNs before locating
the receiving phone. The PSTN uses the call's routing
information to connect to another Gateway that knows where the
receiving phone is located.
- The Gateway located closest to
the receiving phone converts the signal to Globalstar format and
uplinks it to a satellite. This Gateway knows that the receiving
phone is in its contact area because an earlier satellite
relayed that phone's power-on registration message to the
Gateway. This information was stored in the Gateway's Visitor
Location Register (VLR).
- The call is relayed to the receiving phone and the call linkage is complete!
Roaming
The Globalstar system supports phones that are ANSI-41-based and GSM-based over the common Globalstar Air Interface (GAI). The GAI allows an ANSI-41 user to roam to an area served by GSM or vice versa. The Globalstar Gateway provides the ANSI-41 capability and works with a GSM Mobile Switching Center (MSC) for GSM capability. Each Gateway serving an area governed by GSM contains a GSM MSC.
Similarly, if a subscriber with an ANSI-41 Tri-Mode phone roams to Europe, the phone will operate in Globalstar mode using ANSI-41 protocols.
Satellite Constellation
The Globalstar constellation
consists of 48 LEO (low-Earth-orbiting) satellites, plus an
additional four satellites in orbit as spares. Each consists of an
antenna, a trapezoidal body, two solar arrays and a magnetometer,
and operates at an altitude of 1414km (876 miles).
The satellites are placed in eight orbital planes of six satellites
each, inclined at 52 degrees to provide service on Earth from 70
degrees North latitude to 70 degrees South. Because of this
configuration, the polar regions, including most of Greenland, small
parts of Alaska, Canada, Scandinavia, Siberia, and regions in the
Southern Hemisphere, including Antarctica and parts of South America
are not covered.
"Bent-Pipe" Technology
Like "bent-pipes", or mirrors in the sky, the Globalstar
constellation of satellites can pick up signals from over 80% of the
Earth's surface. Several satellites pick up a call, and this "path
diversity" assures that the call does not get dropped even
if a phone moves out of sight of one of the satellites. If buildings
or terrain block your phone signal, a "soft-handover"
takes place, and the call's transmission is switched to an alternate
satellite with no interruption. This satellite now maintains
transmission of the original signal to one of several terrestrial
Globalstar Gateways. Because all the switches and complex hardware
are located on the ground in the Gateways, Globalstar satellites are
relatively simplistic, leading to dramatically increased system
reliability.
Additional advantages of using low-Earth-orbiting satellites within
the Globalstar Communications System include lighter, smaller,
all-in-one handsets and no perceptible voice delay. LEO satellites
also minimize call transmission time delays. Long transmission
delays cause noticeable gaps between the time a caller speaks and
when the listener hears what is being said.
Satellite Footprint
The satellite coverage beams for satellite phone communication links
and the Gateway communication links are quite large. The picture to
the right gives you a sense of scale for the coverage of a typical
thirty-six hundred mile diameter beam footprint.
Each footprint moves rapidly across the Earth's surface. A satellite
that passes directly overhead is visible to that spot for only about
15 minutes.
When a user places a Globalstar satellite call, the nearest
satellite picks up the signal. Globalstar satellite phones can
operate with a single satellite in view, though typically two to
four satellites will be overhead. This simultaneous coverage by
multiple satellites is called "path diversity," which
enhances the quality of the Globalstar satellite call.
Path Diversity
Path diversity is a method of signal reception that combines
multiple signals of varying power strengths into a single coherent
signal. Satellite phones communicate with as many as three
satellites simultaneously, combining those signals into a single,
static-free signal. Globalstar satellite phones also alter power
levels to compensate for shadowing and interference as needed.
As satellites move in and out of view, they will be seamlessly added
to and removed from the calls in progress, reducing call
interruption. This enables the Globalstar system to provide superior
service to a wide variety of locations with less potential for
signal blockage from buildings, terrain, or other natural features.
Globalstar System Technology
Globalstar System Works By
Merging Communications Technologies
The Globalstar™ Communications System merges mobile cellular and
satellite communications technologies and standards to provide a
global roaming solution for cellular phone users. Inside any
cellular service area, a subscriber may roam to other cellular
networks or switch to the Globalstar network.
The Globalstar System Consists Of...
- A satellite constellation of 48 low-Earth-orbiting (LEO) satellites in a 1414 kilometer orbit (878 miles) above the Earth;
- Multiple ground stations called "Gateways";
- The phones that communicate with the satellite (when in Globalstar mode).
QUALCOMM's Role: How It Ties TogetherGlobalstar's constellation transmits calls from your mobile or fixed satellite phone to a terrestrial Gateway developed by QUALCOMM and owned and operated by the Service Provider. These calls are passed through the Gateway and on to existing fixed and cellular telephone networks in more than 100 countries on 6 continents.
Terrestrial Gateways are an important part of Globalstar's strategy to keep key technology and equipment easily accessible and to integrate services as closely as possible with existing local telephony networks. This makes the Globalstar Communications System and its services simple to manage.
QUALCOMM, as designer and leader in the standardization and commercialization of CDMA technology for wireless applications, supplies Globalstar L.P. and Service Providers with:
- QUALCOMM Globalstar Satellite Phones and Products
- QUALCOMM Globalstar Gateways
"Seamless" Phone Service Coverage Is DesiredCellular mobile phone coverage is provided by a network of transceiver antennas clustered on transceiver towers. A network of circles is represented by hexagons. This shows the optimal placement of towers to eliminate "holes" in coverage (an area where mobile phone communication cannot be achieved).
In the real world, coverage holes occur. Obstacles like hills, valleys, or man-made obstructions make the strength of signals between the phone and the cellular antennas inadequate. Mobile phone calls cannot be made or continued when the caller is in one of these holes.
Globalstar Covers The World*Most of the world is NOT covered by cellular networks, whether in wilderness areas, on long-haul trucking routes, or in developing nations.
A satellite phone system gives the consumer a single phone that can be used almost anywhere, whether next door or half-way around the world.
* Except for polar regions or areas not currently covered by installed Gateways, including most of Greenland, small parts of Alaska, Canada, Scandinavia, Siberia, and regions in the Southern Hemisphere, including Antarctica and parts of South America.
Q & A - FAQ
Q.
What is the type of the phone?
A; Thuraya is a satellite mobile phone with integrated GSM and
GPS features.
A: While you are in the coverage area, you can use the Thuraya
phone to call anywhere or receive a call from anywhere in the world.
You will also be able to use the phone on GSM mode in areas with
compatible GSM networks and with whom Thuraya has signed a roaming
agreement, regardless of your location.
Q.
In which countries has Thuraya signed roaming agreements with?
A: For a list of countries with which Thuraya has signed roaming
agreements, please
view Thuraya Roaming partners
Q.
What are Thuraya’s services?
A: Thuraya comes packed with services such as Short Messaging
Services (SMS), fax/data transfer at 9600 bps, voicemail, and call
waiting and forwarding. Global Positioning System (GPS), or location
determination, also comes as a standard feature. In addition, you
will be able to make use of services such as Caller Line Identity
Presentation (CLIP), Call Hold, Call Barring, Call Transfer, and
Conference Calling.
Q.
How many colours do Thuraya handsets come in?
A: Thuraya Hughes 7101 is grey in colour. Thuraya Hughes 7100 and
Ascom
(discontinued product) phones are in dark blue shades.
A: Check the current price on our website.
Q.
Does the Thuraya handset operate indoors? How can the user receive
calls?
A. Thuraya services, like in any other GMPCS system, are intended
for outdoor usage. However the Thuraya system will enable users who
are indoors to receive an alerting signal. He or she can then move
outdoors to start the call. The Thuraya user terminal is dual mode--GSM/Satellite
Thuraya-- and the user also has the option to use GSM while in a GSM
network and indoors.
Thuraya's Fixed Docking Unit (FDU)- the Home/Office Docking product allows the usage of the Thuraya phone in an indoor environment such as home or office. The FDU will complement the Thuraya phone by extending its operations and functionalities inside buildings.
Q.
Is Thuraya phone waterproof?
A: The phone is designed according to GSM specifications, which
normally is not waterproof.
Q.
How long should I charge the battery the first time?
A: To assure maximum performance, always read the
User Manual before attempting to use a THURAYA phone for the first
time. Optimally, a battery will achieve full performance after two
or three complete charge and discharge cycles.
A: Although the charger stops charging automatically when the
battery is full, overcharging may shorten a battery’s life. Hence,
never leave the battery connected to a charger for a very long
period.
A: Phonebook entries are usually
stored on the SIM card. Thuraya lets you save up
to the standard limit of book entries that are allowed in a
SIM card.
Q.
What are the terms of the warranty period?
A: The manufacturers provide a one-year
warranty from the date of purchase. To be eligible for warranty, you
must present your warranty card with the phone and the proof of
purchase at your nearest Thuraya maintenance centre.
Q.
How much does Thuraya phone weigh?
A: The Thuraya phone weighs approximately 220
grams.
Q.
What is the Thuraya code?
A: The Thuraya code is +88216 and each subscriber will have a unique
8 digit number.
Q.
Where can I get more information about Thuraya’s products and
services?
A: The easiest way to know more about Thuraya is through calling us.
You may also visit Thuraya’s website www.thuraya.com
for detailed information about Thuraya. If you have a specific
enquiry or requirement, please contact us or send in your request to
fax +1-305-633-1017, or 2495 NW 35th Av, Miami, FL 33142 USA.
Q.
When did Thuraya’s services begin?
A. Thuraya's commercial services have begun in a gradual roll out,
starting from April 2001 in several countries in Thuraya's coverage
area.
Q. How do I subscribe
to the Thuraya network?
A: You can obtain Thuraya services by contacting us. We will handle
applications, activations and billing. For detailed Thuraya
subscription procedures in your country, please contact our
activations department.
Q.
What are the monthly subscription fees?
A: Please check our current
rates.
A: It varies from one country to another. Nevertheless, the Thuraya
prepaid SIM cards are available without any special requirements or
possible deposits.
Q.
If someone tries to call me on my Thuraya phone while I'm
overseas—what will I be charged?
A: Thuraya applies the calling party pays principle. In most cases, a
Thuraya subscriber will not pay for any incoming satellite calls.
The calling party, on the other hand, will be charged according to
the local telecom provider rates.
Q.
If I’m a Thuraya subscriber, where will I pay my bill?
A: If you have our Thuraya SIM/number, the subscription
and call charges will be paid to Atlantic RadioTelephone, Inc. If
you have a prepaid SIM, however, then there will be a one-time
subscription and activation fee. To keep using it, all you need to
do is buy scratch cards to top up your balance.
Q.
If I am using a GSM card in my Thuraya phone, can I make satellite
calls? Which number would people reach me at?
A: When a subscriber is using a GSM SIM in a Thuraya phone,
the phone acts like a normal GSM phone with your same GSM number. If
your GSM operator has a roaming agreement with Thuraya, you will be
able to roam into Thuraya and make satellite calls. In this case,
you will receive your regular GSM monthly bill with roaming charges
stating usage in Thuraya territory.
Q.
Are there any subscription charges for using my GSM SIM card on a
Thuraya phone?
A: Thuraya charges you
monthly for your Thuraya SIM card only. If you use the service with
your GSM SIM card no subscription charges are applied.
Q.
If there is no Service Provider in my country, how can I obtain
Thuraya services?
A: If you do not have a Thuraya service provider in your country,
please note that Thuraya phone and services can be purchased online
at our e-shop Thuraya.
Q.
How does Thuraya dual mode feature work?
A: With your Thuraya phone and Thuraya SIM, you can make calls via
satellite from anywhere within the coverage area. You also have the
option of roaming from Thuraya into a local GSM operator given that
Thuraya has established a roaming agreement with your local GSM
operator.
With your Thuraya
phone and GSM SIM, you will be automatically accessing your local
GSM operator’s network. Hence, your calls will be billed on your
normal GSM bill. You also have the option to roam into Thuraya’s
network to access satellite services given that Thuraya has already
established a roaming agreement with your local GSM operator.
With a GSM phone
and a Thuraya SIM, you will be roaming from Thuraya into your local
GSM operator network given that Thuraya has already established a
roaming agreement with your local GSM operator. Nevertheless, it
will be impossible to access Thuraya services through your GSM phone
because Thuraya phones have special equipment that makes
communication with the satellite possible.
Roaming
Q. Can you define Roaming in relation to Thuraya?
A. Roaming is a facility that makes:
- Thuraya subscribers (with
Thuraya SIM cards) able to access other GSM networks in the area
using their own SIMs
- GSM
subscribers (with GSM SIM cards) able to access Thuraya
satellite services anywhere in the coverage area using their
existing GSM SIM cards and a Thuraya phone.
Q.
What are Thuraya’s roaming charges?
A: Roaming charges are very similar to the international roaming
call charges and to GSM industry standards.
Solutions
and Accessories
Q.
Does Thuraya have Prepaid scratch cards?
A: Thuraya prepaid scratch
cards will be available at all service provider locations. These
cards can be used only if you have a Thuraya prepaid SIM card and
they work anywhere in Thuraya’s coverage area.
Q. How long is the
validity of a prepaid scratch card?
A: The validity of a prepaid scratch card is three months from
the day you place your first call using the new scratch card.
Q.
Can I receive or make a call on a Thuraya phone while driving?
A: In most cases you will
be able to receive or make calls while driving. To get optimal
reception however, you will need to have direct line of sight with
the Thuraya satellite.
Q.
Does Thuraya have a car kit?
A: Thuraya 'SATMOVE" provides a station for the Thuraya phone
recharging and in-vehicle operations.
Thuraya's
Vehicular Docking Adaptor (VDA) is also available.
Q. What is ‘Fixed
Docking Unit’?
A:The ‘Fixed Docking Unit’
(FDU) allows satellite usage in an indoor environment such as home
or office. It complements the Thuraya phone by extending its
operations and functionalities inside buildings where the satellite
signal is not sufficient. Simply dock the Thuraya phone in ‘FDU’
and you’re ready to use it indoors. All the standard
satellite-based services such as voice, fax/data and the
supplementary services will be available when the phone is docked.
Q. What is included in the Thuraya phone package?
A: Thuraya package comes with a phone, standard battery, SIM
card, travel charger, user manuals, and a warranty card.
Q.
What sort of accessories can I find for Thuraya phones?
A: Thuraya will introduce a whole new range of dynamic phone
accessories to complement its mobile satellite services. The
following accessories are available:
FDU
Vehicular Docking Adaptor (VDA)
Software Package
Standard Battery Pack
How do I use
Data and Fax services from a Thuraya phone?
A: You will need to connect your Thuraya phone to a laptop/computer
with a “Data Cable”(Thuraya Accessory) via a serial port. The
Data Cable can be used to send/receive data and fax at 9.6 kbps.
Global
Positioning System (GPS) and Short Messaging System (SMS)
Q. How do I use GPS on
the Thuraya phone?
A: In the phone menu, you
can access all GPS related features from the “GPS manager”
submenu.
Q.How
can I give my location to someone?
A: After you determine your GPS location, you can send it via SMS to
anyone.
Q.Can
I use Thuraya’s GPS feature if the Thuraya phone is in GSM mode
(even when using an existing GSM SIM card)?
A: As long as you have a
Thuraya phone you will be able to access Thuraya’s GPS feature
regardless of the network you are registered on.
A: No, GPS is a built-in feature and free of charge in all Thuraya
phones.
Q. What is the
Thuraya SMS center number?
A. The Thuraya SMS center number is "+882161900000”
A: Please follow
the procedure below:
- Go to menu.
- Choose
"Settings".
- Then choose
"SMS Parameter".
- Then choose
"SMS Center".
- Enter
"+882161900000” as the SMS center number.
Since Thuraya
considered a virtual country, always use full country codes and
numbers when sending SMS messages.
Q.
In what languages does Thuraya phone support SMS?
A: Thuraya phone supports SMS in English, Italian, French, and
German.
Technology
Q. Why
is there a requirement for a large L-band antenna?
A: To enable the user to transmit low power using Thuraya’s
handheld terminal, the spacecraft will require high sensitivity or
high G/T to receive the signal. From the transmission side of the
spacecraft, the system also requires a high gain antenna to provide
high power, quality signals to the individual handheld users.
Q. What is the excess
power that the satellite transmits during shadowing?
A: Thuraya system will provide a 10 dB fade margin to handheld users
for typical shadowing.
Q. What is the handset
power in the satellite mode?
A: Thuraya’s transmitted power of a maximum of 2 W, is similar to
the GSM 900. The power control in both systems is the same. This
means that the mobile terminal will not transmit the maximum power
when it is not needed.
Q. Why is the Thuraya
terminal antenna thickness larger than the normal GSM handset
antenna?
A: The Thuraya user terminal operates on a dual frequency of GSM 900
MHz and satellite at a 1.6/1.5 GHz range and therefore requires
additional hardware for such dual band operations. The Thuraya
handset uses a Quadrifilar helical L-band antenna consisting of
helices wound on a cylinder, which give it a larger in size compared
to normal GSM antennas.
Q. What are the main
differences between the Primary Gateway and the national gateways?
A: The primary gateway contains a gateway station which serves as
the link between the fixed and mobile public terrestrial networks,
both for originating and terminating calls. The primary gateway is
also equipped with:
The Satellite Operation Center (SOC) which operates and maintains the satellite
The Advanced Operation Center (AOC), which is responsible for the radio resource management of the satellite traffic channels.
The Central Operation Support System (OSS) which provides the functions for customer care, billing and SIM card personalization for the entire network (including the NGWs)
The National Gateway contains a
gateway station but not the SOC, AOC, and OSS. However, a local
Operation and maintenance Center could be provided.
Each GW (including PGW) is assigned to manage a subset of the
satellite resources and serve a specific region in the ground.
However, the primary gateway is designed to manage more subsets and
more regions than any national gateway.
Q. What is the effect of
the radiation of the Mobile Terminal to the human body?
A: The results of the Specific Absorption Rate test (SAR= power
absorbed per unit mass of tissue) shows that the power of the
handheld terminal with the antenna (in both the extended/deployed
and retracted/stowed positions) meet the European and IEEE/ANSI
standards--even for Satellite Mode (GEM) on 9.6 kbps data mode.
Q. What is the modulation
type?
A: Thuraya’s carrier modulation is QPSK
Q. What is Thuraya’s
blocking rate?
A: The average blocking rate is less than 2%
Q. What security features
are built into the Thuraya links?
A:. Thuraya uses encryption which is equivalent in robustness to the
standard GSM encryption.
Q. What is the size of the
Thuraya spacecraft L-band antenna?
A: 12.25m (40 ft) X 16m (52 ft)
IP Videophone
Satellite Phone FAQ - Answers: |
Satellite
phone is a subscription radio service. It's
similar to cable television, in that it provides a wide range of
programming not available on traditional AM/FM radio for a monthly
fee.
back to top
What does satellite phone offer?
A
|
Satellite Phones vs. Cellular Phones
The way cellular phones work they use zones or small base stations called “cells”. As you move from one area or “cell” your call is “handed off” from the old to the new cell. The switch to the new cell is accomplished by the sending of a special signal to the mobile unit. The Mobile Telephone Switching Office or MTSO connects the cellular calls with the Public Switched Telephone Network or (PSTN). The MTSO also controls all the cell sites. All the cell phones are registered with the control channel so the system knows where to find the cellular phone.
Imagine in a perfect world the cells or zones looked like a large honey bee cone that covered the planet. But this is not possible. It is not cost effective for the cellular providers to put up cell towers in rural areas or many third world countries where there would be low usage. So this makes vast areas of the U.S. and other countries where a cellular phone does not have coverage because if you are not close to a cell tower your cell phone will not work. There is also the issue where your friend's cell phone may work in an area or “cell” and yours does not. That is because their phone is most likely using another cellular provider the uses a tower with a difference technology other than the technology compatible with your phone. Also it would be impossible to place towers out in the ocean far from land, again making your celullarl phone worthless when not close to a cell tower.
Satellite Phones do not use “cells” or cell towers. The most popular hand held satellite telephones use Low Earth Orbiting or LEO satellites. When you turn on your satellite phone the signal goes up to any number of satellites in a compatible constellation where it is then registered with the constellation. Globalstar has 48 satellites and Iridium has 66 that orbit the earth. When making a call the satellite signal goes to the satellites this it is directed down to a ground station or gateway where it is directed by the gateway the to the call destination. The call can be directed to a land-line or PSTN as well as a cellular network. The reverse is also true. Any land-line or cellular network can call satellite phones. The Gateway processes and takes care of the switching of the calls rather than the satellite network. This allows you to use your phone even when you are in the middle or no where far from any cell tower. If you call another compatible satellite phone the call is transmitted up to the satellites and then down to the ground station then transmitted back up to the satellites then down to receiving satellite phone. This is the ultimate secure calling because the encryption is handled at the ground station because the call never goes to a land-line or PSTN.Globalstar is a consortium of leading international telecommunications companies originally established in 1991. The Globalstar system is designed to provide high quality satellite-based services to a broad range of users, including:
· Voice calling
· Short Messaging Service (SMS)
· Roaming
· Positioning
· Facsimile
· Data transmission
Globalstar meets the needs of cellular users who roam outside of coverage areas, people who work in remote areas where terrestrial systems do not exist, residents of under-served markets who can use Globalstar's fixed-site phones to satisfy their needs for basic telephony, and international travelers who need to keep in constant touch.
The Globalstar constellation consists of 48 LEO (Low Earth Orbiting) satellites, with an additional four satellites in orbit as spares, and operates at an altitude of 876 miles (1414 km) in space.
When all Gateways are fully deployed, Globalstar constellation of
48 Low Earth Orbiting (LEO) satellites will pick up signals from
over 80% of the Earth's surface, everywhere outside the extreme
polar regions and some mid-ocean regions. Download map for current
and projected coverage:Globalstar Coverage Map (44K)
Coverage Map (390K)
Several satellites pick up a call, and this "path diversity" assures that the call does not get dropped even if a phone moves out of sight of one of the satellites. As soon as a second satellite picks up the signal and is able to contact the same terrestrial "gateway", it begins to simultaneously transmit. If buildings or terrain block your phone signal, this "soft-handoff" prevents call interruption. The second satellite now maintains transmission of the original signal to the terrestrial "gateway".
Additional advantages of using Low Earth Orbiting satellites within the Globalstar system include no perceptible voice delay and lighter / smaller all-in-one handsets.
The satellites utilize a "bent-pipe" architecture. On any given call, several satellites transmit a caller's signal via CDMA technology to a satellite dish at the appropriate Gateway. Gateways process calls, then distribute them to existing fixed and cellular local networks. Terrestrial gateways are an important part of Globalstar's strategy to keep key technology and equipment easily accessible and to integrate our services as closely as possible with existing local telephony networks. This makes the Globalstar system and its services simple to manage, expand and improve.
The Globalstar satellite is simple and proven. Each consists of an
antenna, a trapezoidal body, two solar arrays and a magnetometer.General Characteristics:
Total weight - 450kg,
Number of Spot beams - 16
Power - 1100W
Lifetime - 7.5 years
Allocated frequencies:
|
Direction
|
Frequency
|
|---|---|
| Globalstar Phone-Satellite | 1610-1625,5MHz |
| Satellite-Globalstar Phone | 2483,5-2500MHz |
| Satellite-Gateway | 6875-7055MHz |
| Gateway-Satellite | 5091-5250MHz |
Whether you're in need of a satellite-based mobile phone for travel or a fixed phone for remote but economical on-site communication, Globalstar offers world-class products and services, including high quality voice, roaming and Short Messaging Service (SMS), and later in the year 2000 positioning, asynchronous dial-up fax and data services up to 9,600 bps.
Globalstar's mobile satellite phones, only slightly larger than traditional cellular phones, are built by three of the world's top wireless manufacturers, Ericsson, Qualcomm and Telit. These phones are multi-mode and work with terrestrial AMPS, CDMA, or GSM networks, as well as the Globalstar satellite network. Fixed phone options include models manufactured by Ericsson and Qualcomm, and public payphones, built by Schlumberger. A wide assortment of accessories is also available for increased freedom in the field, in your car or on your boat.
With the original service start on November 1,
1998, Iridium LLC (founded in 1991 and having invested about $7
billion) announced the end of commercial service on March 17,
2000. The service had been relaunched on March 28, 2001. The
concept for the Iridium system was proposed by Motorola engineers
Ray Leopold, Ken Peterson, and Bary Bertiger. They envision a
constellation of low orbiting satellites. Research and development
began in 1987.The Iridium system was backed by 19 strategic investors from around the world: AIG Affiliated Companies, Iridium Africa Corporation, Iridium SudAmerica Corporation, Iridium Middle East Corporation, Khrunichev State Research and Production Space Center, Lockheed Martin Corporation, Iridium Canada, Inc., Iridium China (Hong Kong) Ltd., Iridium India Telecom Limited, Iridium Italia S.p.A., Raytheon Company, SK Telecom, South Pacific Iridium Holdings Limited, Sprint Iridium, Inc., Thai Satellite Telecommunications Co., Ltd., Motorola, Inc., Nippon Iridium (Bermuda) Limited, Vebacom Holdings, Inc., Pacific Asia Communications Ltd., Seventeen investor partners also participated in the operation and maintenance of 12 ground station "gateways" that link the Iridium satellite constellation to terrestrial wireless and landline public telephone networks. The 12 gateway operators also served as regional distributors of Iridium services in their designated commercial territories. Iridium operated constellation of 66 satellites in low earth orbit, at an altitude of 485 miles (780km).
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66 Iridium LEO satellites provide 100% Global Coverage. Although
there are four Countries which do not operate.These are Hungary,
Poland, N. Korea and N. Sri Lanka. Coverage Maps are divided into
two categories: Voice Maps and Paging Maps. Paging maps contain
Message Delivery Areas. (see Iridium
Pagers for more detailes)
The IRIDIUM system is a satellite-based, wireless personal
communications network designed to permit any type of telephone
transmission - voice, paging, facsimile or data - to reach its
destination anywhere on Earth.It revolutionized communications for business professionals, travelers, residents of rural or undeveloped areas, disaster relief teams, and others who need the features and convenience of a wireless hand-held telephone with a single worldwide number.
Unlike conventional telecommunications networks, the satellite-based system tracks the location of the telephone, providing global transmission even if the subscriber's location is unknown. In areas where compatible cellular service is available, the dual-mode telephone provides the option of transmitting a call via the local cellular system.
IRIDIUM telephones provides high-quality voice connections and interface with laptop computers, personal digital assistants, palmtop organizers, and other communications equipment.
The relatively short distance reduces the delay and enhances the quality of the telephone conversation. Each satellite covers an area 4,000 Km Wide. The phone call is transferred from cell to cell and from satellite to satellite as the spacecraft rise and set during their orbital motion (approximately one revolution around the earth per hour). The Gateways are continuously linked to at least two satellites of the constellation.
66 operational plus 6 in-orbit backup satellites are located in 6
orbital planes with the inclination of 86.4 degrees. Orbital
period 100 minutes, 28 seconds.General Characteristics:
Satellite weight - 700 kg (1500 lb),
Spot beams - 48 per satellite,
link margin - 16 decibels (average),
lifetime - 5-8 years.
Allocated frequencies:
|
Direction
|
Frequency
|
|---|---|
| Iridium Phone-Satellite | 1616-1626.5MHz |
| Satellite-Iridium Phone/Pager | 1616-1626.5MHz |
| Satellite-Satellite | 23.18-23.38GHz |
| Satellite-Gateway | 19.4-19.6GHz |
| Gateway-Satellite | 29.1-29.3GHz |
With the Iridium system all communications services - Voice and Paging - are delivered regardless of the user location or the availability of traditional telecommunications networks.
A variety of subscriber equipment is available to communicate with the Iridium network, including dual-mode handsets, specialized aeronautical and marine units, numeric and alphanumeric pagers.
An Iridium Portable Telephone is quite similar to a conventional hand-held cellular terminal. Dimension, weight, battery lifetime were like terrestrial cellular phones. Still, it can operate in dual-mode, that is cellular mode or Iridium mode: the Iridium terminal is also a cellular terminal and could be used where cellular networks are available.
An Iridium Pager offeres the first true "global roaming" capability in a small, belt-worn, personal message receiver.
Established in 1979 to serve the maritime industry
by developing satellite communications for ship management and
distress and safety applications, Inmarsat currently operates a
global satellite system which is used by independent service
providers to offer an unparalleled range of voice and multimedia
communications for customers on the move or in remote locations.
While continuing to perform its original mandate, Inmarsat has
since expanded into land, mobile and aeronautical communications,
so that users now include thousands of people who live or work in
remote areas without reliable terrestrial networks, or travellers
anywhere. Users such as journalists and broadcasters, health teams
and disaster relief workers, land transport fleet operators,
airlines, airline passengers and air traffic controllers,
government workers, national emergency and civil defence agencies,
and heads of state.The Inmarsat satellites are located in geostationary orbit 22,223 miles (35,786 km) out in space.
Inmarsat covers about 98% of the land mass area.Download map from here:
Inmarsat Coverage Map (43.0Kb)
Inmarsat Coverage Map (380.0Kb)
R-BGAN provides coverage in 99 countries.Download map from here:
Inmarsat Coverage Map (855.0Kb)
Each satellite covers up to one third of the Earth's surface and
is strategically positioned above one of the four ocean regions to
form a continuous 'world-wide web in the sky'. Every time a call
is made from an Inmarsat mobile satphone it is beamed up to one of
the satellites. On the ground, distributed all around the world,
giant communications antennas are listening for the return signal,
which they then route into the ordinary telephone network. And
when someone calls an Inmarsat customer, it happens the same way -
but in reverse.According to different use and purposes Inmarsat System is divided in several standards.
Inmarsat mini-M. Inmarsat's most popular service, designed to exploit the spotbeam power of the Inmarsat-3 satellites, the latest Inmarsat mini-M phones are the smallest, lightest and cheapest ever made. Weighing about 2kg and the size of a notebook computer, prices range from $3,000 for the phoe and $2.5 a minute airtime. Maritime, land, vehicular and semi-fixed versions are available.
Inmarsat-GAN. Introduced in the end of 1999, provides Global Area Network(GAN) services, including speech at 4.8 Kbps, fax and high speed data (up to 64 Kbps), ISDN, IPDS(Inmarsat Packet Data Service), Internet access, E-mail access, video conferencing.
Inmarsat R-BGAN. Introduced on November 18, 2002, provides superfast links to the Internet, corporate intranets and key business applications, such as e-mail, web browsing, file transfer, Virtual Private Networks and e-commerce.
Inmarsat-A. The original service introduced in 1982, providing direct-dial telephone, fax, data, telex and e-mail.
Inmarsat-B. Introduced in 1993, this is a digital successor to Inmarsat-A. It offers servicec similar to those of Inmarsat-A, but with sugnificant reduction in call cost due to its more efficient use of radio frequencies.
Inmarsat-C. A two-way, packet data service via lightweight, low-cost terminals, small enough to be hand-carried or fitted to any vessel, vehicle or aircraft. Approved for use under the Global Maritime Distress and Safety System (GMDSS), and ideal for distributing and collecting information from fleets of commercial vessels or vehicles.
Inmarsat-D+. Offers global two-way data communications using terminals no bigger than a personal CD player. Complete with integrated GPS, D+ system are ideally suited for tracking, short data messaging, and supervisory control and data aquisition. (SCADA) applications.
Inmarsat-E. Provides global maritime distress alerting services transmitted from emergency position indicating radio beacons (epirbs) and relayed through Inmarsat coast earth stations. Covers vertually all of the world's ocean areas and is fully compliant with the Global Maritime Distress and Safety System (GMDSS).
Inmarsat-M. The world's first personal, portable mobile satellite phone introduced in 1993, making possible telephone, Group 3 fax and data calls from a briefcase-sized terminal. Also available in maritime versions with radome antennas as small as 70cm in diameter.
Aero-C. A low-cost messaging and data reporting service providing aircraft with store-and-forward satcoms. Ideal for aircraft flying in regions where radio communication is difficult or impossible. In addition to its proven position repoting facility, Aero-C can be used for weather and flight plan updates, maintenance and fuel requests, and business and personal communications.
Aero-H. Introduced in 1990, offering telephone, fax and data communications in aircraft passenger cabins and cockpits. It is also used for airline operations and air traffic control.
Aero-I. An intermediate-gain telephone, fax and data services for short and medium-haul aircraft that operates within Inmarsat-3 spotbeams and makes possible a new generation of smaller, lighter and cheaper avionics and antennas.
Aero-L. A low-gain aeronautical satcom service offering real-time, two-way air to ground data exchange at 600bps. Complies with International Civil Aviation Organization(ICAO) requirements for safety and air traffic control.
Aero mini-M. Designed for small corporate aircraft and general aviation users, for voice, fax and 2,4Kbps data. Externally mounted antenna links to a small terminal weighing about 4.5 kg. Particulary useful in areas beyond the reach of VHF radio.
The four Inmarsat-2 satellites were built by an international
consortium headed by the Space & Communications division of
British Aerospace (now part of the Anglo-French company Matra
Marconi Space). Subcontractors included Hughes Aircraft Company
(US), Fokker (The Netherlands), Matra (France), MBB (Germany),NEC
(Japan), and Spar (Canada). Satellite ground control operations
contractors included CLTC (China), CNES (France), SED (Canada),
Telespazio (Italy), and Intelsat.Inmarsat-2 is a
three-axis-stabilized satellite design based on the Eurostar
satellite platform, developed by British Aerospace and Matra
Espace (both now part of Matra Marconi Space). The satellites were
designed for a 10-year life. At launch, each weighed 1,300 kg, had
an initial in-orbit mass of 800 kg and 1,200 watts of available
power. The communications payload has two transponders, providing
outbound (C- to L-band) and inbound (L- to C-band) links with
mobile terminals in the 6.4/1.5 and 1.6/3.6 GHz bands. The
effective L-band isotropic radiated power (EIRP) is 39 dBW. Each
satellite's global beam covers roughly one-third of the Earth's
surface. Depending on demand, bandwidth and EIRP can be
dynamically allocated for communications for maritime,
aeronautical and land mobile applications.Spacecraft 2F1 Located POR 179 deg East
Back-up spacecraft for Inm3-F3
Launched October 30, 1990 by Delta rocket
Originally in service (IOR) December 8, 1990
Spacecraft 2F2 Located AOR-West 98 deg west
Carries leased services and also a back-up spacecraft for Inm3-F4
Launched March 5, 1991 by Delta rocket
Originally in service (AOR-E) April 13, 1991
Spacecraft 2F3 Located IOR 65 deg East since March 4, 1997
Back-up spacecraft for Inm3-F1
Launched December 16, 1991 by Ariane rocket
Originally in service (POR) January 19,1992
Spacecraft 2F4 Located AOR-West 109 deg East
Carries leased services
Launched April 15, 1992 by Ariane rocket
In service May 31, 1992
US-based Lockheed Martin Astro Space built the spacecraft bus, the structure and systems that serve as the satellites basic utilities, based on the Astro Space Series 4000.UK-based Matra Marconi Space built the communications payload which included antennas, repeater and other communications electronics.The communications payload operates in the C- and L-band portions of the radio spectrum. Each satellite has its antennas and electronics tuned for optimum coverage of a particular area on Earth, known as its footprint.The tremendous advantage of the Inmarsat-3 satellites is their ability to concentrate power on particular areas of high traffic within the footprint. Each satellite utilises a maximum of seven spot beams and one global beam. The number of spot beams will be chosen according to traffic demands. In addition, these satellites can re-use portions of the L-band frequency for non-adjacent spot beams, effectively doubling the capacity of the satellite. Each satellite weighs about 2,066 kg at launch, compared to 1,300 kg for an Inmarsat-2 satellite. The satellites produce up to 48 dBW of EIRP - the effective isotropic radiated power, a measure of how much signal strength a satellite can concentrate on its service area.
Spacecraft 3F1 Launched April 3, 1996 on Atlas Centaur IIA
Lift off from Cape Canaveral
On-station location 64.0 degs east (IOR)
In-service date 11th May 1996
Spacecraft 3F2 Launched September 6, 1996 on Proton D-1-E
Lift off from Baikunur
On-station 15.5 degs west (AOR-E)
In service date 06:00 13th October 1996
Spacecraft 3F3 Launched December 18, 1996 on Atlas Centaur IIA
Lift off from Cape Canaveral
On-station location 178 degs east (POR)
In service date 17:50 25th January 1997
Spacecraft 3F4 Launched June 3, 1997 on Ariane 4
Lift off from Kourou, French Guiana
On-station location 54 degs west (AOR-W)
In service date 26th July 1997
Spacecraft 3F5 Launched February 3, 1998 on Ariane 4
Lift off from Kourou, French Guiana
On-station location 25 degs east
Carries leased services and also a back-up spacecraft for Inm3-F2
Three Inmarsat I-4 satellites to be lauched in 2004 and are currently under development of Astrium (previously Matra Marconi Space). New satellites will be 100 times more powerfull to provide speeds up to 432Êbps. Advanced technology will allow to reduce service cost by around 75% compared to existing Inmarsat-M4 charges. New service will be identified as B-GAN - Broadband Global Area Network.
Established in April 1997 in the UAE as a private joint stock company, Thuraya has a shareholder base made up of 18 prominent telecommunications operators and investment houses. As of today Thuraya has more then 100 000 subscribers.
Thuraya offers following Telecommunications Services:
- Voice
- Fax at 9.6 Kbps
- Data at 9.6 Kbps
GSM Standard Supplementary Services:
Call Forwarding, Call Barring, Calling Line Identification, Closed User Group, Multiparty, Call Waiting, Short Messages Service, SM Beam Broadcast
Value Added Services/ Intelligent Network Services:
Pre-paid SIM Card Services, Hot Billing Services, Free Phone Service, Premium Rate Service, IVR Services, Voice Mailbox Service
Thuraya Design Features:
Optimised Routing to provide most economic call routing,
Single hop for UT-UT calls, anywhere in the coverage area,
Thuraya Country Code: + 882 16 X….X,
Accurate definition of country and Service Provider boundaries,
Network Access and Call Tariff are based on caller terminal GPS position,
Use of Common Air Interface: CAI is "open standard"
First Thuraya satellite is located in geostationary orbit
Thuraya provides coverage in 99 countries of the world:
Afghanistan, Albania, Algeria, Andorra, Armenia, Austria,
Azerbaijan, Bahrain, Bangladesh, Belarus, Belgium, Benin,
Bhutan, Bosnia Herzegovina , Bulgaria, Burkina Faso, Cameroon,
Central African Republic, Chad, Croatia, Cyprus, Czech Republic,
Denmark, Djibouti, Egypt, Eritrea, Estonia, Ethiopia, FR of
Yugoslavia, France, Gambia, Georgia, Germany, Ghana, Gibraltar,
Greece, Guernsey, Guinea, Guinea Bissau, Hungary, India, Iran,
Iraq, Ireland, Isle of Man, Italy, Ivory Coast, Jersey, Jordan,
Kazakhstan, Kuwait, Kyrghyzstan, Latvia, Lebanon, Liberia,
Libya, Liechtenstein, Lithuania, Luxembourg, Macedonia, Mali,
Malta, Mauritania, Moldova, Monaco, Morocco, Nepal, Netherlands,
Niger, Nigeria, Oman , Pakistan, Palestine, Poland, Portugal,
Qatar, Romania, Russia, Saudi Arabia, Senegal, Sierra Leone,
Slovakia, Slovenia, Somalia, Spain, Sri Lanka, Sudan,
Switzerland, Syria, Tajikistan, Togo, Tunisia, Turkey,
Turkmenistan, Ukraine, United Arab Emirates, United Kingdom,
Uzbekistan, Yemen.Thuraya’s Mobile Satellite System comprises three key segments:
-
Space Segment
-
Ground Segment
-
User Segment
Two Thuraya Satellites were and third one is being built by
Boeing Satellite Systems. The satellites are designed for a
12-15 year life. The satellite is equipped with an innovative
40-foot (12.25-meter) L-band transmit-receive reflector
provided by TRW Astro Aerospace. The large reflector is
combined with Boeing’s on-board digital signal processing to
create an active phased-array antenna that allows the
spacecraft to create more than 200 spot beams and handle
13,750 simultaneous phone calls. The digital signal processor,
five times more capable than any previous Boeing digital
processor, has more computing power than 3,000 Pentium
III-based computers.Payload Subsystem:
-
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:
- FDMA carrier channel BW 27.7 kHz
- Channel bit rate is 46.8kbps
-
Bus Subsystem:
Solar - Beginning of life 13KW
- End of life 11KW
- Panels are 2 wings of 4 panels each w/dual-junction gallium arsenide cells
Batteries
-250 A-hr cells
Dimensions In orbit
- L, solar arrays 34.5 m (113ft)
- W,antenna 17m (55.7 ft)
Stowed
-H:7.6m (25 ft)
-W:3.75m * 3.75m (12.3 ft)
Weights - 5250 kg (11,576 lb) Launch
- 3200 kg (7,056 lb) In orbit (beginning of life)
Allocated Frequencies:
|
Direction
|
Frequency
|
|---|---|
| Thuraya Phone Phone-Satellite | 1626.5-1660.5MHz |
| Satellite-Thuraya Phone | 1525.0-1559.0MHz |
| Gateway-Satellite | 6425.0-6725.0MHz |
| Satellite-Gateway | 3400.0-3625.0MHz |
Satellite Location:
Located 44 deg East
Launched October 21, 2000 on board a Sea Launch Zenit-3SL rocket from the equator in the middle of the Pacific Ocean by Delta rocket
To be located 28.5 deg East
To be launched in January 2003
To be located 87 deg East
Launch date is not determined
Thuraya handsets are very compact and look almost like GSM phone. See Video Clip (10.0 Mb) about using Thuraya phone.
Thuraya's handsets are being manufactured by 2 major suppliers: Hughes and Ascom.
No matter where you are - Thuraya gives coverage: On open sea, in the middle of a desert - outside of GSM coverage; Thuraya is there!
List
of available Thuraya accessories
Thuraya
satellite coverage area
How to
call Thuraya from a landline telephone
How to
GSM roam woth a Thuraya phone
How to
set up your Thuraya phone as modem
Thuraya
visual guide
Download
the Thuraya manual
Thuraya
short codes and service numbers
Call
charges
|
Download manual To download the manual in english, you need to have pdf-reader |
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How Iridium Works
Iridium essentially is a satellite-based cell-phone system. Similar to a ground-based Global System for Mobile communicat