Quick Start Guide

coordinates In 3 dimensions with approximately 1m accuracy.
The AirFinder Precise Location Service consists of the following hardware components:
• AirFinder Location Beacon (LB) or Location Beacons (LBs)
• AirFinder Access Point (AP) or Access Points (APs) (also referred to as Aggregators)
• AirFinder Gateway (GW) or Gateways (GWs)
Location Beacons (LBs) provide the input data for the AirFinder Precise Location Service.
Location Beacons rapidly broadcast short data packets at 2.45GHz; these broadcast packets are called
beacon messages. These beacon messages are transmitted multiple times per second, and the on-air time
of each beacon is very short - measured in microseconds.
AirFinder asset tracking tags scan for Location Beacon advertisement messages, calculate their location,
connect to an Access Point, and transmit that location.
AirFinder Access Points support 2.4 GHz Radio Access network using a proprietary protocol referred to as
XLE, for AirFinder 3.0 Devices. AirFinder Access Points (APs) are installed at a facility in a configuration to
provide complete and redundant XLE network coverage for Devices. APs, like Location Beacons, broadcast
a frequent and periodic beacon message; however, the AP beacon message is different than the Location
Beacon message. These AP beacons are also heard by AirFinder asset tracking tags, but not used by the
tags in the standard location algorithm. An AirFinder tag scans for available APs and attempts connection
to the first one it detects. In almost all cases, the asset tag will receive beacon messages from multiple
APs in any location within a facility.
When an AP receives an uplink message from an asset tracking AF3.0 tag (i.e. a location update message
with the tags xyz coodinates in meters referenced to a pre-defined origin on a scale accurate floor plan),
it transmits this message to an AirFinder Gateway. APs use an FCC-certified over-the-air-protocol called
Symphony Link
TM
, which operates in the 902-928 MHz frequency band, to communicate with Gateways.
Link Labs is the creator of the Symphony Link Protocol and the AirFinder Gateways.
Like APs, Gateways are installed at a site to provide comprehensive and redundant Symphony Link
coverage. This Symphony Link Network is an Internet of Things (IoT) network service layer for all Access
Points. Access Points communicate Alert messages to Gateways. When a Gateway receives a message
from an Access Point, it acknowledges to the Access Point that the message was received.
Access Points have several other functions, in addition to aggregating up-link messages from AF3 asset
tracking tags. Location Beacons also periodically connect to Access Points to send a heartbeat (i.e. “still
alive”) message. This short heartbeat message contains the LB MAC ID and also the current voltage of the
batteries of the LB. Access Points also regularly send their own heartbeat message to Gateways, indicating
that the Access Point is connected and functioning properly. AF3 asset tracking tags also transmit a
heartbeat message periodically.
If, or when, the configuration of Location Beacons or Staff Alert Devices need to be changed, the
configuration change will be transmitted from the AirFinder Precise Location Service Platform through a
Gateway down to the Access Points. Location Beacons and AF3 Asset tracking tags connect to Access
Points when transmitting their heartbeat message, and check for a mailbox message at that time to
determine if there are new configuration settings to download. If there are, then the LB or Device, updates