First, IndoorAtlas indoor positioning works without beacons but they will help iPhone to get first position quickly without any walking. Depending on the use case, the required beacon coverage can vary from placing beacons only to places where the sessions usually start to very coarse overall coverage to more or less full coverage.
The most optimal solution, the lowest number of beacons and the best coverage, can be achieved by using incremental approach. Incremental workflow could go through the following steps:
1) Map the initial state
3) Add beacons to problem areas
4) Add mapping to area with new beacons
5) Repeat from #2 if necessary
The same with more words:
1) Map the location as it is originally. Remember to enable Bluetooth before start mapping. After the mapping is done, generate the map.
This allows to check if there were any pre-installed beacons you might not be aware of. It happens often that e.g. shop owners in the mall have installed their own beacons or an infotainment display acts also as a beacon.
2) Check the mapping results at app.indooratlas.com to verify the beacon status
Areas without beacon coverage can be easily seen on the map analytics. (Select the draft map and change to beacon environment quality view)
Above is a real life example (a shopping mall floor) of the initial state. It was expected to have no beacon coverage at all. The analytics shows there is very good coverage on the mid part. On the other hand, the left side of the floor is missing beacons totally, as well as the very end of right side. In this case, the next step is to place one additional beacon on the right end and three beacons to left side. This will produce full coverage.
3) Add beacons to empty areas (red areas in the analytics picture). Pay attention to areas where users often enable the positioning, enter/exit the floor
The focus areas are e.g. entries, exits, info desks, elevators, staircases and escalators. On the other hand, the beacons should be installed so that the signal of the beacon would not be received on other floors to avoid challenges in floor detection.
4) Add mapping data to the areas with new beacons to include them in the data.
After adding the new beacons, collect additional path or paths on the area where the new beacons were added. This inserts the beacons on the positioning map. Remember to generate the map after mapping.
Picture shows the places of the newly added beacons, old mapping paths and the new path we added in the example case. In this case the signal strength of the beacons and the placement added full coverage to the target area. There was still a small empty spot left on the bottom right of the map but it was thought to be OK, since it’s not expected to get any sessions started there. The dot will follow there accurately by magnetic data.
The area which one beacon covers depends on the beacon type/model and the configuration parameters, but also the place where the beacon is installed plays a significant role. Depending on the beacon characteristics, a beacon signal may form a cone shaped beam directly out from its cover. This causes that:
- If this kind of beacon is installed on the ceiling, its beam is directed downwards and it’s heard only in a limited area underneath and in close proximity (5-10 meter radius)
- On the other hand, if such beacon is installed on the wall, its beam can be received rather far, 10-30 meters from the beacon but only in the limited direction, where the transmission beam is directed.
When deciding the placement, it is good to understand the characteristics of the beacon model you are installing. That information can be utilized when placing the beacons and maximizing the coverage and at the same time, limiting the coverage only to the desired floor.
Moving a Beacon
Rarely, but sometimes there can be a case, where an existing beacon needs to be moved. Moving a beacon can cause an issue if it remains on the map, as it can lead the positioning algorithm to a faulty decision. Avoiding the issue is easy; change the minor code of the beacon you move. This way when it will be heard from its new location it will be recognized a totally new beacon. Naturally, you need the add mapping to the new place to add it into the map. The analytics of the old place won’t change until you remap the old location. Therefore, analytics might seem too optimistic, as the system thinks the beacon still exists there – until you re-generate the map.
Configuring the Beacons
Good beacon configuration parameters are important to optimize the beacon coverage and battery life. IndoorAtlas positioning utilizes the beacons mainly for quick first location and therefore the frequency can be lower than for beacon based positioning. For a very quick first fix 1 Hz is a safe value. Even lower frequency produces very good results, you can test the best values for you use case. During the mapping time, higher frequency (e.g. 1 Hz) is recommended. Changing the frequency after the mapping is totally fine and it does not require new mapping.
The most suitable beacon transmission power depends on the beacon type, its beam form and the beacon placement. Therefore, it’s challenging to give good common guidelines, and it’s better to check the values from the beacon provider’s datasheet, keeping in mind the desired coverage area.
This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 738580