perating and Installation
CDMA Service (Aeris, Verizon, Sprint)
CDMA is an abbreviation for
technology was originally developed for military applications but was eventually commercialized.
This communications standard is widely used in North America and in some parts of Asia and
Rather than dividing calls
into time slots like GSM, CDMA allows all users to transmit at the
same time. Each call is accompanied by a unique digital code that allows it to be differentiated
from the rest. As an analogy suppose you are in a crowded room and many conversations are
taking place at the same time. Your brain is able to distinguish the conversation you are having
with your friend because it is able to focus on your friend’s voice characteristics. As the room
grows more crowded each person must talk louder and the siz
e of the conversation “zone”
grows smaller. You may have to move closer to your friend to keep the conversation going.
Thus the number of conversations is limited by the overall interference and noise in the room.
A cellular account must be activated
with a cellular service provider prior to placing a
The service provider may ask the device type, which must be specified as the “
CDMA Packet (Internet) Service
ingle carrier, radio transmission technology (1X or 1XRT
added to a standard voice plan, or may be a stand
Packet service packages are generally priced by the number of bytes to be transferred rather
than by the minute. Typically the smallest available package
will be 1 megabyte (1 Mb) per
month. The amount of data that the
will produce depends upon what sort of data is
The amount of information exchanged on each call may range from
several hundred bytes to 10’s of thousands of
bytes. It may be necessary to test the system for
several months and then adjust the cellular account for the best cost based on your needs.
requires full Internet access because the data collection software could be running on
ted anywhere in the world.
Full access is usually assigned to customers who will
be connecting a cellular modem to a personal computer.
One parameter that will be needed is the packet service connection command. In most cases
but you may want to check with your service provider.
CDMA Circuit Switched Data (CSD) Service
The service provider must support asynchronous circuit
switched data (CSD) exchange at the
baud rate of the central computer’s modem.
ty may be included as part
of a standard voice package or it may be an add
on feature at extra cost.
One consideration when ordering service is the frequency of calls to and from the
service provider offers different packages that may includ
e a fixed number of minutes per month
for a fixed price. However, when this number is exceeded, the cost per each additional minute
To Next Page
Loading...
Need help?
General
