User's Manual

UE910 3G HARDWARE USER GUIDE 1vv0301171 Rev.3 • 2015-04-17 51 of 78
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6.4 Antenna Requirements
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.
The antenna and antenna transmission line on PCB for a Telit UE910 device shall fulfil the following
requirements:
PCB design guidelines
When using the UE910, since there's no antenna connector on the module, the antenna must be
connected to the UE910 antenna 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 UE910, then a PCB line is
needed in order to connect with it or with its connector.
This transmission line shall fulfil the following requirements:
Item
Value
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 WCDMA Band V
140 MHz in WCDMA Band II
Impedance
50 ohm
Input power
> 24dBm Average power
VSWR absolute max
≤ 10:1 (limit to avoid permanent damage)
VSWR recommended
≤ 2:1 (limit to fulfill all regulatory requirements)
Item
Value
Characteristic Impedance
50 ohm
Max Attenuation
0,3 dB
Coupling
Coupling with other signals shall be avoided
Ground Plane
Cold End (Ground Plane) of antenna shall be equipotential to
the UE910 ground pins