xE70-915 RF Module User Guide
1VV0301106
rev.3 – 2015-03-04
Reproduction forbidden without written authorization from Telit Communications S.p.A. - All Rights
Reserved.
Page 28 of 34
6.4.
Antenna connections on printed circuit
boards
Special care must be taken when connecting an antenna or a connector to the module. The RF
output impedance is 50 ohms, so the strip between the pad and the antenna or connector must
be 50 ohms following the tables below. Ground lines should be connected to the ground plane
with as many vias as possible, but not too close to the signal line.
PCB material
PCB thickness H (mm)
Coplanar line W (mm)
Coplanar line G (mm)
FR4
0.8
1
0.3
1.6
1
0.2
Table 1: Values for double face PCB with ground plane around and under coplanar wave guide
(recommended)
PCB material
PCB thickness H (mm)
Coplanar line W (mm)
Coplanar line G (mm)
FR4
0.8
1
0.22
1.6
1
0.23
Table 2: Values for simple face PCB with ground plane around coplanar wave guide (not recommended)
