Global
System for Mobile Communication
The GSM
network was developed to simplify the use of cell phones for both
users and operators alike. With a GSM cell phone the main benefits
are: Users are able to make and receive calls in any GSM country
whilst retaining just one cell phone number. They only have to pay
for one line rental on that number. Operators only have to bill
one number per user.
The system was pioneered in Europe
but has since expanded around the globe; to date GSM is available
in over 130 countries worldwide. The most widely used GSM frequencies
are 900, 1800 and 1900MHz.
Iridium Satellite Phone System
Iridium is a low-orbit satellite
system that allows calls to be made and received from anywhere in
the world. Although the system has global coverage, it is not licensed
to work in all countries so please contact us for specific details.
One of the advantages of using this satellite phone is that there
is no charge for incoming calls, features include data compatibility
of 2.4 Kbps (not compatible with Apple Macintosh) please check compatibility
with your internet service provider.
Advanced
Mobile Phone System
AMPS was the original cell phone
system developed in North America. It works with what is now considered
‘out dated’ analog technology, digital systems called
TDMA and CDMA have been developed to replace it. However, AMPS is
still going strong and although digital quality is better than analog,
AMPS can still offer the widest available cell phone service in
North America and parts of South America, especially in more rural
locations.
For this reason Mobal still provide AMPS compatible
cell phones for use in these areas.
Time Division
Multiple Access
TDMA (also known as D-AMPS) was developed as
a digital standard to work along side the old AMPS standard. Special
dual band cell phones are able to switch between areas covered by
the AMPS standard and areas covered by the TDMA standard automatically.
TDMA is most widely used in the US. Outside the
US, TDMA networks can be found in places around the world including
Latin America and parts of Asia and the Caribbean.
Code Division
Multiple Access
This is the latest digital standard being developed.
It aims to provide a more efficient cell phone service than TDMA
by being able to handle a greater number of calls at one time.
There are now CDMA networks around the world,
including Japan, Latin America, Australia, Canada, Hong Kong, Israel
and South Korea.
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