Bluetooth Mesh Networking with nRF52840 Boards - Range and Power Consumption Details

[Ronak Gohil]

As a beginner working with the nRF52840 board and implementing BLE Mesh between two devices, it's essential to understand the range limitations and power considerations to ensure reliable communication and efficient energy usage.

My questions about what is the  maximum communication range and power consumption.

[tesc]

Hi,

Bluetooth mesh builds on top of Bluetooth 4, and provides range through relaying messages Each transfer between two neighboring nodes is called a hop, and each such hop can span a distance from a few meters to a few tens of meters, depending on the surroundings. Line-of-sight and few other RF sources nearby leads to the longest range. Packets in a Bluetooth mesh network can do a maximum of 127 hops.

In Bluetooth mesh, normal nodes must use the radio at all times in order to receive messages. They must stay in RX whenever not transmitting, since there is no time synchronization for the communication and incoming packets can come at any point in time. Radio RX power for nRF52840 is 3.7 mA or 6.7 mA depending on which regulator is used, and some CPU usage as well as other peripherals will come on top.

There also are Low Power Nodes (LPM), which have significantly lower power consumption, down to a few tens of uA. Those nodes require a Friend node in the network for receiving messages.

For more information on Bluetooth mesh, please consult the Bluetooth mesh documentation for nRF Connect SDK, in particular the Bluetooth mesh concepts section. I can also recommend the Introduction to Bluetooth mesh webinar recording. For a more in-depth walk-through of Bluetooth mesh development with the nRF Connect SDK, we have the webinar Developing Bluetooth mesh products: Introduction.

Regards,
Terje