NRF52 and NRF51 (Beacon) Range

[Usman Rashid]

I want to know about some range information of the NRF52 & NRF21 (BEACON).

For example if I have TX power of the beacon +4 dBm and which is broadcasting every 500 ms so what would be the range of the beacon?

What is the the amount of heat that nordic BLE device dissipate ? for example if NRF52 is my receiver so do I need any heat sinks in my product ??

What is the maximum range of NRF52 and NRF51 beacon ?

[Jørn]

Hello Usman

The range of a beacon is very hard to determine as it is highly dependent on the receivers surroundings. With 4 dBm transmit power, and -96 dBm sensitivity for a dirty receiver (page 230 of the nRF52832 product specification, the nRF51 series has the same sensitivity) you have a link margin of 100dB.

If we disregard all sources of loss, assume direct line of sight and calculate the range with Friis equation we get around 1km. However that's not realistic at all, as we will have plenty of loss on the way.

If you subtract matching loss (let's assume 5 dB per device), fading (let's say 20 dB) and compensation for noise from additional sources (let's say 6 dB) You would then be left with a margin of 100-5-5-20-6=64 dB. Friis equation would then give you about 15 meters range. But if your receiver is located in a more noisy place, let's say our noise compensation is raised to 12dB instead of 6, you end up with 58 dB, which corresponds to about 7,5 meters range. Add a more severe case of fading, changing it from 20 to 30 dB, you're down to almost 3 meters.

If you were outside, rain or snow would further affect your range by further increasing fading.

In addition to the examples mentioned above there are many other things that could potentially affect your margins, such as moving objects, fluorescent light (they contain plasma), doppler shifts etc.

As for heat dissipation, you will not need any heat sinks for the chip. Maximum power consumption might be around 60mW if everything is active at once, however most of the time the hardware would be turned off. This leads to heat dissipation being very low.

Best regards

Jørn Frøysa