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: