Wirnet iBTS
Document title : Installation and
Maintenance Manual
Version : 2.0
Author : SNI
Date : 04/12/2018
Classification
This document is the strict property of Kerlink and shall not be either copied nor sent without express
written authorization of Kerlink
Internal Use
Kerlink m2m technologies reserved rights
Confidential
Kerlink – 1 rue Jacqueline Auriol – 35235 THORIGNÉ-FOUILLARD
Page 167 / 221
Strict confidential
The LoRa antenna requires an open environment to optimize the link with the end-points.
The benefits are less multipath fading and optimized coverage area.
The antenna is provided with a 1m coaxial cable. Extension coaxial cables of could be used to
reach a better position but are not provided by KERLINK. However, beware of the insertion
losses!
4.5.2.2
Distance between antennas
4.5.2.2.1
LoRa antenna vs. LTE antennas
To avoid or minimize the intermodulation between the LoRa transmitter and the LTE
transmitter, a minimum distance is required between the LoRa antenna and the LTE
antenna. This minimum distance is also recommended to avoid mutual desensitization of the
receivers.
With the Wirnet iBTS standard casing, it is very simple to ensure the required distance
between antennas because they have separated antenna brackets.
With the Wirnet iBTS compact casing, the separation between antennas is more complex as
the LTE antenna is internal (cannot be moved apart) and the LoRa antenna could be
mounted on the universal antenna bracket tightened to the compact casing mounting kit.
To optimize the colocation between the internal LTE antenna and the external LoRa antenna,
a distance of 20 cm is required between both radiated parts.
Therefore, when possible we strongly recommend dissociating the universal antenna bracket
away from the compact enclosure support. This is the best way to guarantee the 20 cm min
distance between LTE antenna and LoRa antenna.
When the dissociation is not possible, the LoRa antenna must be placed on the right side of
the enclosure as described on Figure 102.
Figure 102 : Position of the universal antenna support when mounted on the compact enclosure support
LoRa antenna
Universal antenna
bracket on the
right side
20 cm
Internal LTE
antenna area
