Cătălin Huzum 
Philip Vann In the past few years there has been an increase in the demand for indoor tracking and location services, as many new technologies came to the fore with new capabilities, at reduced costs. One of the technologies for doing such indoor tracking and indoor navigation is Bluetooth beacons. This paper will review two of the most common uses of Bluetooth beacons, and the types of situations they are best suited for.
The most common approach to such a solution uses fixed beacons, placed in coordinated positions, relative to an indoor map. Bluetooth-enabled mobile devices recognize these beacons when in range and determine the device position on the map, using the signal strength of the acquired beacons as a measure of distance and knowledge of the beacon locations.
Given the nature of the Bluetooth signal, which can be affected by any obstacle between the sender and the receiver, various techniques can be used to get a reliable location. These enable the tracking of a Bluetooth-enabled device (be that a phone, tablet or other smart device) with the help of the Bluetooth beacons. The tracking data that can be gathered from each mobile device can then be sent to a centralized system for analytic purposes, and other services such as real-time heat mapping.
One practical example of this approach might be a digital tour around a museum, where each room or attraction could have a fixed beacon emitting a specific Bluetooth signal. If a person chooses to install the museum's mobile app, as they walk near a beacon, their phone would pick up the signal and relevant, targeted information regarding the exhibit could be pushed to each device to enable a more informative and engaging visitor experience.
Another approach for Bluetooth beacon tracking which is becoming increasingly feasible as the cost of equipment goes down involves having fixed Bluetooth 'listener' devices rather than the mobile devices outlined above. These fixed 'listeners' will pick up any Bluetooth beacons in their range, and transmit the information gathered to a centralized system for analytics.
The central system will apply some signal filtering and, based on the location of the fixed listeners which has been programmed in to the system, it determines the position of the beacons - a simple reversal of the concept outlined above. Using this approach, instead of tracking a mobile device, the tracking of individual beacons is achieved, which enables a number of new and innovative use cases.
For example, Accenture Mobility created a 'Connected Conference' solution for one major trade show, in order to gather data about how much time people were spending at different elements of the event and run analytics to gather insight accordingly. Participants who agreed were given small, coin-size Bluetooth beacons to carry around with them, which would interact with Bluetooth 'listeners' that had been positioned at demo stands and in meeting rooms across the event. In this case, Accenture created a dashboard display which - perhaps unsurprisingly - showed that people were most consistently gathered near the coffee bar, but depending on the occasion, use case and business objective, such a system is able to gather:
only anonymous metrics such as real-time attendance and event analytics: This can also benefit attendees and beacon carriers who would be able to - for example - download an app enabling them to query the central system for real-time seat occupancy
Other use cases of this listening approach might include tracking tools, assets or parts in a factory, where beacons can be attached to assets and listeners can be installed along the production line.
The benefit of this approach for the system owner will be that they have access to real-time tracking data but also to analytical data about the amount of time, for example, certain parts remain in one part of a factory.
There are multiple challenges to be considered when building such a system, from back-end to front-end, to mobile and embedded application development, but this simple method of monitoring where moving parts are travelling and how long they are lodged in certain places uses very little bandwidth, and is becoming cheaper all the time.
From a hardware perspective, the use of 'listener' beacons relies on them being small and light enough to be carried or attached with ease to whatever is being monitored. Fortunately, there are a lot of options available on the market, with very different shapes, specifications and price tags.
Beacons use Bluetooth Low Energy (Bluetooth v4), which is energy efficient and which thus minimizes any impact on battery life. There are standard beacon protocol specifications like iBeacon (developed by Apple) or Eddystone (developed by Google), but many other 'open' formats are also available and widely used.
When it comes to the Bluetooth listening devices, virtually any Bluetooth-enabled connected device (increasingly known as 'Internet of Things' connected devices) can be used, from a general purpose Raspberry Pi or Arduino, for example, to custom designed devices. The listening device will decode the beacon message format. Beacons can transmit sensor data as part of their messages, which can also be incorporated into the solution.
Depending on the use case, the central system can either be a cloud or an on premise solution, but it needs to be able to handle all data shared by the 'listener' devices in real time (or perhaps in batches if configured that way), process that data and then aggregate the analytics in order to deliver insight back to the system owner. A system should also be able to manage the provisioning of all devices, both beacons and listeners, in order to get everything up and running quickly and smoothly.
Due to the increased demand and use cases for indoor tracking technologies, and the reduced activation costs, Bluetooth beacon tracking has great potential for indoor location. Backed up by the rapidly growing number of IoT devices, many of which support Bluetooth as standard - the number of use cases for this type of technology is expected to grow considerably. With the Bluetooth v5 standard right around the corner promising a far greater range, speed of communication and improved energy efficiency along with other features, we expect the development and widespread applicability of this technology to increase for both the applications of Bluetooth outlined in this paper, and for probably many more too!
by Cassian Lup
by Claudia Mihu
by Oana Călugar
