System Description

TD 93025US
9 May 2019 / Ver. I 54
System Description
teleCARE IP
9.3 Wireless Infrastructure
The use of a full wireless infrastructure is an extension on the existing wireless functionality
and is intended for use in independent living and in assisted living facilities.
In an environment consisting mainly of wireless devices, a full wireless infrastructure can be
achieved using a wireless gateway (NIRC3 + NUREP) in combination with wireless repeaters
(NUREP).
The wireless gateway can serve up to 12 repeaters divided into three subnets each
containing a maximum of four wireless repeaters (nodes). In a subnet, a node must always
be installed in such a way that it is able to contact the next and previous node in the subnet
in sequential order of installation / configuration. The first node added to a subnet must be
able to contact the wireless gateway.
Note: A wireless repeater (node) can only communicate with the previous and next node in
a subnet, communication from node to node between subnets is not possible.
Figure 46. Full wireless infrastructure example
The wireless repeaters communicate with each other through a secondary transceiver
operating on the 2.4GHz band (IEEE 802.15.4).
Note: Note: To minimize the risk of interference with other wireless networks in the 2.4GHz
range, for example Wi-Fi, a site survey should be performed to evaluate the RF
environment.
For Wi-Fi the 802.11b standard recommends the use of non-overlapping operating
channels 1, 6 and 11 for North America. Although this operating practice is not mandatory,
it is often employed where multiple access points are in use. In the US and Canada, Wi-Fi
channels 13 and 14 are not used, therefore the wireless repeater channel 25 can be used
for operation clear of Wi-Fi interference.
When deploying a teleCARE wireless infrastructure in an environment where resource
planning and bandwidth allocation can be guaranteed, a proper wireless repeater channel
clear of Wi-Fi interference can be selected to ensure acceptable co-existence with Wi-Fi.