A Practical Guide to Setting Up BLE (Bluetooth Low Energy) Beacons for Accurate Tracking in Hazardous Areas

Bluetooth Low Energy (BLE) beacons have become a valuable technology for adding location tracking capabilities to your hazardous areas. With the right planning and configuration, BLE beacons can provide accurate indoor and outdoor location. This allows organisations to cost-effectively add location tracking of personnel and assets whilst reducing the total cost of ownership. 

This article provides practical guidance on deploying BLE beacons to achieve optimal tracking performance. It covers indoor and outdoor setup considerations, best practices for beacon placement, and configuration tips for maximizing location accuracy. 

What is the difference between a beacon and anchor? 

For trilateration purposes it is recommended to use beacons. A beacon is simply a term used to describe a fixed beacon that is contributing to a tag’s position. An anchor is typically the term used when discussing Wirepas Mesh networks.  

How BLE Trilateration works 

BLE trilateration works in the same way as Wi-Fi trilateration. RSSI (Received Signal Strength Indicator) varies at each beacon. BLE beacons are placed on the map in the location engine.  

A BLE beacon will transmit in a 3-dimensional omni direction as shown in Figure 1. 

Figure 1

The tag receives the RSSI and sends that information along with its MAC address to the location engine. ​The location engine then calculates where the tag is within those beacons and places it on the map.​ 

An example solution of this would be the Extronics iTAG X-Range of worker safety tags, the iTAG XB40 BLE beacon and the Extronics Location Engine (ELE).   

Indoor BLE Beacon Placement 

For indoor tracking, BLE beacons should be positioned in square or triangular patterns whenever possible. This allows the tag to receive signals from multiple BLE beacons to trilaterate its location. General guidelines include: 

• Space beacons 10-15 meters apart to ensure overlap in a room 
• Place near entrances/exits to detect room transitions   
• Avoid obstructions like metal that can interfere with signals 
• Mount on walls or ceilings for widest transmission range 

A triangular grid ensures reliable coverage across a whole floor. More beacons can fill gaps and improve accuracy. With at least three BLE beacons detected, the tag’s location can be narrowed down to a precise point on a map. 

If two BLE beacons are used and the tag receives equal RSSI values from both beacons, the tag will be positioned in the middle of the beacons as shown in Figure 2.

Figure 2 

If the tag receives a stronger RSSI value from beacon 1 then the tag will be positioned closer to beacon 1 as shown in Figure 3. 

Figure 3 

Figure 4 shows an example deployment layout for accurate positioning in the Hallway, Stairway and Rooms 2, 4 and 5 and room level positioning in Rooms 1 and 3. 

Figure 4

Outdoor Setup Considerations 

Positioning the BLE beacons outside is much the same as indoors, where a triangular pattern is recommended. BLE beacons can transmit signals, line of sight, over 100 metres. However, for accurate location tracking using trilateration the distance between BLE beacons depends on the environment. 

• Place BLE beacons next to key infrastructure like buildings or equipment 
• Reduce transmit power or range in software settings if needed  
• Use metal shielding to shape transmission range if necessary 
• 10-50 meter spacing is typical outdoors depending on environment 

By placing BLE beacons strategically around outdoor assets, workers can be accurately tracked when they are in the vicinity of those assets. For example, it may be important to know when a worker is next to a piece of equipment. Figure 5 shows BLE beacons 1 placed onto or next to the equipment. This would then place the worker next to that asset. 

In some instances where there are multiple people in one area, it may be better to use ‘fix to centre’ setup. For example, in a muster zone where multiple tags may be in close proximity to a set of beacons. If a BLE tag comes into the proximity to a beacon, the location engine will fix its position to the centre of the beacon on the map rather than trying to position multiple tags in such a small area. By fixing each tag to the centre point of that area, it aggerates the tags into a list and gives a much clearer picture of which tags are present in this location. In these scenarios it is important to ensure beacon coverage does not overlap and cause inaccurate positioning from surrounding beacons. Configuration settings can be adjusted in the location engine to accommodate these scenarios.  

Figure 5 – BLE Beacon fixed to asset with surrounding wireless connectivity

Final Comments 

Some trial and error will be required to tune these parameters for your specific environment. It is not an exact science, and each site will have different challenges, but BLE systems provide the flexibility to calibrate for your unique requirements. 

In summary, with thoughtful planning and configuration, BLE beacons can provide invaluable location tracking. Following the best practices above will help maximise performance indoors and out. Expert assistance is also recommended to ensure your system is optimised and tailored to your use cases.