User's Guide

HE863 Family Hardware User Guide
1vv0300891 Rev.5
- 2011-03-18
Reproduction forbidden without Telit Communications S.p.A’s. written authorization - All Rights
Reserved. Page 53 of 89
7.4. GPS Antenna Requirements (HE863-EUG/NAG/AUG
only)
The use of combined GPS antennas is NOT recommended; this
solution could generate an extremely poor GPS reception and
also the combination antenna requires additional diplexer and
adds a loss in the RF route.
The module is provided of an Antenna supply circuit with the
following characteristics:
 Supply voltage referred to VBATT (Must accept values
from 3.4 to 4.2 V DC)
 Supply enable controlled internally by the BB.
When using the Telit HE863-EUG/NAG/AUG, since there’s no
antenna connector on the module, the antenna must be connected
to the HE863-EUG/NAG/AUG through the PCB with the antenna pad
using a 50 Ohm transmission line.
In the case that the antenna is not directly developed on the
same PCB, hence directly connected at the antenna pad of the
HE863-EUG/NAG/AUG, then a PCB line is needed in order to
connect with it or with its connector.
This line of transmission shall fulfill the following
requirements:
ANTENNA LINE ON PCB REQUIREMENTS
Impedance
50 ohm
No coupling with other signals allowed
Cold End (Ground Plane) of antenna shall be equipotential to
the HE863-EUG/NAG/AUG ground pins.