Facts about cellular transmission
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2001 Nokia Mobile Phones. All rights reserved.
5. Reference Information
Facts about cellular transmission
Your car phone employs the data transmission capabilities of
the GSM network to send faxes, short messages and e-mail and
to establish connections with remote computers.
GSM data capabilities of your car phone
- Data compression with V.42bis
- Non-transparent and transparent data transfer at 9.6kbit/s
-AT commands
(for further information, see Nokia 6090 Product Support on
www.forum.nokia.com website)
- Fax service classes 1, 2 and 2.0 and ECM (sending)
- SMS sending and receiving
Cellular data connections can be made from most of the loca-
tions where your car phone operates. However, we recommend
that you move the car to a location where the strongest possible
cellular signal can be obtained. When the signal is strong, data
transmission is efficient.
In general, you should not expect the same performance from
cellular data communications as from line-connected commu-
nications due to the inherent characteristics of the cellular en-
vironment. The following factors may impair cellular
connections:
Noise
Radio interference from electronic appliances and equipment as
well as from surrounding traffic may impact the transmission
quality.
Handover
As the car phone user moves from one network cell to another,
the signal strength of the channel drops and the cellular tele-
phone exchange may hand the user over to a different cell and
frequency where the signal is stronger. A cell handover may also
occur when the user is stationary due to varying cellular traffic
loads. Such handovers may cause slight delays.
Dead spots and dropouts
Dead spots are areas where radio signals cannot be received.
Dropouts occur when the car phone user passes through an area
where the radio signal is blocked or reduced by geographic or
structural obstructions.
Low signal strength
Due to either distance or obstacles, the radio signal strength
from a cell site may not be strong or stable enough to provide
reliable cellular connection for communication. Therefore, to
ensure the best possible communication, remember to take the
following points into consideration when using your car phone: