SQ864
GPRS Terminal
13
Sales: +44 (0) 118 967 9000
Fax: +44 (0) 118 976 9020
www.sequoia.co.uk
Rev 2.1.4 Jan 2011
Wireless Technology
Experience The Freedom
9. Terminal installation considerations
There are several conditions which need to be taken into
consideration when designing your application as they might affect
the terminal and its functionality. These are:
Environmental conditions: The terminal must be installed so that
the environmental conditions stated such as temperature, humidity
and vibration are satisfied. Additionally, the electrical specifications
must not be exceeded.
GSM Signal strength: The terminal/antenna has to be placed in a
position that ensures sufficient GSM signal strength. To improve
signal strength, the antenna can be moved to a more elevated
position. Signal strength usually depends on how close the modem
is to GSM base station. You must ensure that the location at which
you intend to use the modem is within the network coverage area.
Degradation in signal strength can be the result of a disturbance
from another source, for example an electronic device in the
immediate vicinity. When the application is operational, you can
verify signal strength by issuing the AT command:
AT+CSQ
See “AT+CSQ Signal Strength” in the AT command manual
Tip: Before installing the modem you can use an ordinary mobile
telephone to check the signal strength in each possible installation
location. Sequoia Technology can also provide a GSM signal tester
which provides a full breakdown of the GSM signal received. Please
contact Sequoia Technology for more information. http://www.
sequoia.co.uk
When considering the location for the modem and antenna
placement, you must consider received signal strength as well as
cable length as long cable runs can attenuate the received signal
strength.
Connections of components to SQ864-GPRS: The system
integrator is responsible for the
final system solution. If external components are incorrectly
designed or installed it may cause radiation limits to be exceeded.
For instance, improper cable connections or incorrectly
installed antennas can disturb the network and lead to terminal
malfunction.
Network and Subscription: Before your application is used, you
must ensure that your chosen network provides the necessary
telecommunication services. Contact your service provider to
obtain the necessary information.
•
If you intend to use SMS in the application, ensure this is
included in your subscription.
•
Consider the choice of the supplementary services such
as GPRS, Voice and CSD.
