User's Manual

GE910 Hardware User Guide
1vv0300962 Rev.12 2013-10-22
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved
page 36 of 83
Mod. 0805 2011-07 Rev.2
6. GSM Radio Section
The antenna connection and board layout design are the most important aspect in the full
product design as they strongly affect the product overall performances, hence read carefully
and follow the requirements and the guidelines for a proper design.
6.1. GSM Antenna Requirements
As suggested on the Product Description the antenna and antenna transmission line on PCB for a
Telit GE910 device shall fulfill the following requirements:
ANTENNA REQUIREMENTS
Frequency range
Depending by frequency band(s) provided by the network
operator, the customer shall use the most suitable antenna
for that/those band(s)
Bandwidth
70 MHz in GSM850, 80 MHz in GSM900, 170 MHz in
DCS & 140 MHz PCS band
Impedance 50
Input power > 2 W
VSWR absolute max  10:1 (limit to avoid permanent damage)
VSWR recommended  2:1 (limit to fulfill all regulatory requirements)
When using the GE910, since there's no antenna connector on the module, the antenna must be
connected to the GE910 antenna pad (LGA pad K1) by means of a transmission line
implemented on the PCB.
In the case the antenna is not directly connected at the antenna pad of the GE910, then a PCB
line is needed in order to connect with it or with its connector.
This transmission line shall fulfill the following requirements:
ANTENNA LINE ON PCB REQUIREMENTS
Characteristic Impedance 50
Max Attenuation 0,3 dB
Coupling with other signals shall be avoided
Cold End (Ground Plane) of antenna shall be equipotential to the GE910 ground pins