User's Guide

LE910Cx HW User Guide
Doc#: 1VV0301298
Rev. 13.0 Page 60 of 124 2019-07-15
7. Antenna(s)
Antenna connection and board layout design are the most important parts in the full
product design, and they have a strong influence on the product’s overall performance.
Read carefully and follow the requirements and guidelines for a good and proper design.
GSM/WCDMA/TD-SCDMA/LTE Antenna Requirements
The antenna for the LE910Cx device must meet the following requirements:
Table 19: Primary Antenna Requirements
Frequency range
The customer must use the most suitable antenna bandwidth
for covering the frequency bands provided by the network
operator and supported by the OEM while using the Telit
module.
The bands supported by each variant of the LE910Cx module
family are provided in Section 2.6.1, RF Bands per Regional
Variant.
Gain
Gain < 3 dBi
Impedance
50 Ohm
Input power
> 33 dBm(2 W) peak power in GSM
> 24 dBm average power in WCDMA & LTE
VSWR absolute max
<= 10:1 (limit to avoid permanent damage)
VSWR
recommended
<= 2:1 (limit to fulfill all regulatory requirements)
Since there is no antenna connector on the LE910Cx module, the antenna must be
connected to the LE910Cx antenna pad (AD1) by a transmission line implemented on the
PCB.
If the antenna is not directly connected to the antenna pad of the LE910Cx, a PCB line is
required to connect to it or to its connector.
This transmission line must meet the following requirements:
Table 20: Antenna Line on PCB Requirements
Characteristic impedance
50 Ohm
Max attenuation
0.3 dB
Avoid coupling with other signals.
Cold End (Ground Plane) of the antenna must be equipotential to the LE910Cx ground
pads.