RE: nRF52811 direction finding compatibility

Simonr — Tue, 09 Jul 2019 12:35:19 GMT

Hi Martin and Peter

It will not be possible to use older chips as AoA transmitters/beacons, as according to the Bluetooth specification, you have to send "special direction finding signals" which won't be possible to send from chips not supporting Bluetooth 5.1. It is possible to send AoA transmissions in other ways as Quuppa does, but this will be out of the Bluetooth spec. and therefore proprietary. So to implement direction finding in nRF products that are in line with the Bluetooth spec, both transmitter and receiver must be Bluetooth 5.1 compatible.

This blog post includes more info on the topic of direction finding in Bluetooth.

Best regards,

Simon

PS: I will be out of office for the remainder of the week, so replies for any follow-up questions will be delayed! Sorry for the inconvenience.

RE: nRF52811 direction finding compatibility

niebert — Tue, 09 Jul 2019 11:16:59 GMT

That is what it is made for and the bill of materials could be extremely cheap! Precision remains to be seen: the IQ samples are 12bit which introduces discretisation noise in addition to signal noise, also multipath reception can cause problems.