Sony Ericsson GM29, Integrator'S Manual, Page: 42 / 264

GM29 INTEGRATOR’S MANUAL
42
LZT 123 7361 R1B
Caution!
Do not exceed a torque of 25Ncm when tightening the fixings screws.
Excessive torque applied to the screws can crack the plastic case.
5.3 Antenna
5.3.1 General
The antenna is the component in your system that maintains the radio
link between the network and the modem. Since the antenna transmits
and receives electromagnetic energy, its efficient function will depend
on:
• the type of antenna (for example, circular or directional);
• the placement of the antenna;
• communication disturbances in the vicinity in which the antenna
operates.
In the sections below, issues concerning antenna type, antenna
placement, antenna cable, and possible communication disturbances are
addressed.
In any event, you should contact your local antenna manufacturer for
additional information concerning antenna type, cables, connectors,
antenna placement, and the surrounding area. You should also
determine whether the antenna needs to be grounded or not. Your local
antenna manufacturer might be able to design a special antenna suitable
for your the application.
5.3.2 Antenna Type
Make sure that you choose the right type of antenna for the modem.
Consider the following requirements:
• the antenna must be designed for the dual frequency bands in use:
EGSM/GSM900/1800;
• the impedance of the antenna and antenna cable must be 50
Ω
;
• the antenna output-power handling must be a minimum of 2W;