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| A. The
initials stand for Global System for Mobile Communications.
GSM is an open, non-proprietary system that is constantly evolving.
One of its great strengths is the international roaming capability.
This gives consumers the same standards and the same number
of contact abilities in more than 159 countries. GSM satellite
roaming has extended service access to areas where terrestrial
coverage is not yet available. |
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Q.
Is there a health risk-using mobile phones?
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| A. There
is no present reliable evidence that mobile phones constitute
a health hazard. Research is on-going to check whether the relatively
low power of the transmitted signals can effect human cells.
The GSM Association in collaboration with WHO are constantly
researching on this issue. |
| A. GSM
has been designed to be very secure system. Transmission protocols
and algorithms are constantly being enhanced and added to the
system. GSM remains the most secure public wireless standard
in the world. |
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Q.
What is the GSM Association?
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| A. The
GSM Association, which is based in Dublin and London UK, represents
the interests of more than 490 GSM, satellite and 3G operators,
key manufacturers and suppliers to the GSM industry as well
as regulatory and administrative bodies from more than 159 countries
and regions worldwide. Most of the first 3G licencees are also
members. The GSM Association is responsible for the continued
maintenance of open standards and inter-operability. The global
cooperation between operators is most powerfully demonstrated
by the success of international roaming. One of the Association
's major priorities is the development and promotion of the
GSM standard worldwide. |
| A. The
GSM Association has developed the world's leading billing standard
TAP3 which allows operators to exchange billing information
for roaming and enables billing for a host of new services that
networks intend to offer their customers |
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Q.
What is Multiple access scheme?
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| A. The
multiple access scheme defines how different simultaneous communications,
between different mobile stations situated in different cells,
share the GSM radio spectrum. A mix of Frequency Division Multiple
Access (FDMA) and Time Division Multiple Access (TDMA), combined
with frequency hopping, has been adopted as the multiple access
scheme for GSM. |
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Q.
What are FMDA and TDMA?
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| A. frequency
is assigned to a user in the FMDA scheme. This frequency will
be dedicated completely to that user until the user discontinues
his service. Since the radio spectrum is not infinite, there
is a lmit to the number of frequencies (users) which can be
assigned.. On the other hand TDMA allows users to share the
number of frequencies available. Each user is assigned his own
'burst' within a group of bursts called a 'frame'. TDMA is normally
used with an FDMA structure. |
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Q.
How are the GSM frequencies used by the user?
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| A. In GSM,
a 25 MHz frequency band is divided, using a FDMA scheme, into
124 carrier frequencies with a separation of 200 kHz between
the bands. Normally a 25 MHz frequency band can provide 125
carrier frequencies but the first carrier frequency is used
as a guard band between GSM and other services working on lower
frequencies. Each carrier frequency is then divided in time
using a TDMA scheme. This scheme splits the radio channel, with
a width of 200 kHz, into 8 bursts. A burst is a time width of
approximately 0.577ms in the TDMA system. A TDMA frame consists
of 8 bursts and therefore lasts 4.615 ms. Each of the eight
bursts, that form a TDMA frame, are then assigned to the single
user. |
| A. High
bandwidth services already exist in 2G technologies. However,
the future will be 3G with added possibilities of sophisticated
data and multimedia applications. The GSM standard will continue
to evolve, with wireless, satellite and cordless systems offering
greatly expanded services. These will include high speed, multimedia
data services, inbuilt support for parallel use of such services
and seamless integration with the Internet and wireline networks. |
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Q.
What is 3G? Is it the same as UMTS?
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| A. 3G or
third generation is the generic term used for the next generation
of mobile communications systems. These new systems will provide
enhanced voice, text and data services to those available today.
Global groups such as the Third Generation Partnership Project
(3GPP) are currently developing the concepts for 3G systems
across the industry. The GSM Association's vision of 3G is based
on today's GSM standard, but evolves to include an additional
radio air interface better suited for high speed and multimedia
data services. |
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Q.
Will my current mobile phone cease to work when 3G systems
are launched?
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| A. There
will be a period of co-existence with 2G and 3G systems. 3G
systems are based on 2G infrastructure and services, but offer
a new radio interface, among other features. The current 2G
mobile phone will continue to operate, and it will be up to
the user to decide whether he wants to opt for the 3G services.
For doing this, the user will need to upgrade. |
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Q.
Will 3G systems be truly worldwide and how can I find out
about developments in my own country?
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| A. It is
likely that there will be up to three types of technology deployed
in 3G. These systems are being harmonised to ensure they are
compatible with one another and that they will accept multi-mode
handsets. This integration of systems and services will give
users worldwide roaming. Your national regulatory authority
is the best and most accurate source of information on 3G license
availability in your country. Besides, the GSM Association also
compiles this information, as it becomes available |
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