User's Manual

GE865 Hardware User Guide
1vv0300799 Rev.11 – 13-07-2010
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 38 of 82
7 Antenna
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.
7.1 GSM Antenna Requirements
As suggested on the Product Description the antenna and antenna transmission line on
PCB for a Telit GE865 device shall fulfil 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
Gain
1.4dBi @900 and 3dBi @1800
1.4dBi @850 and 3dBi @1900
Impedance
50Ω
Input power
> 2 W
VSWR absolute max
≤ 10:1 (limit to avoid permanent damage)
VSWR recommended
≤ 2:1 (limit to fulfil all regulatory requirements)
When using the GE865, since there's no antenna connector on the module, the antenna
must be connected to the GE865 antenna pad (BGA Ball H5) 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 GE865, then
a PCB line is needed in order to connect with it or with its connector.