Bluetooth Asset Tracking

[philippfa]

Hi

I have a short question:

I am currently writing on my master thesis about an self built Asset Tracking System. There should be a micro controller as a receiver and a bluetooth device (e.g. bluetooth beacon) for sending the signal. It is then possible to calculate the distance between the receiver and sender to track the assets (products) in the production hall. So there is a way to find out where your product is.

One of the main questions is how many bluetooth devices can be tracked at each scan. But this is hard to test because of the need of many devices at the same time. I even don’t know how many I would need to test it (eg: 15, 25, 50 or so).

So I would like to ask if you know how many devices can be tracked at each scan with the bluetooth chip in your devices.

I would like to know it, if possible, for the nRF52840 Dongle.

I would be very happy, if you can help me.

Best regards,

Faber Philipp

[Marjeris Romero]

Hi Faber,

There isn't any specific limit of number of beacons that can be scanned by a observer (scanner) device in the Bluetooth specification. The limitations will depend on each use-case. For example the scan window and scan interval of the observer and the advertising interval of the broadcasters (beacons).

There will be a limitation if there are a lot of beacons advertising very fast, since there will be noise in the same bandwidth and this will cause packet corruptions so the observer will not be able to see all the packets because of CRC error filtering in the hardware.

Other sources of noise in the 2.4MHz band (e.g WiFi) will also limit the amount of beacons you can have before there is too much noise in the bandwidth.

So there is no easy way to answer your questions and the easiest solutions to know the maximum number of beacons you can have in a given enviroment is to test it yourself, but of course you can try to do some modelling and calculate an approximate number for different uses cases as a part of your project. Good luck!

Keep in mind that for bluetooth connections there is a limit of 20 concurrent connections per device.

Best regards,

Marjeris