Sensitivity, 125 kbps BLE mode

[Ellison]

hi,

For NRF52840, is the 125kbps sensitivity the same as on Radio? I used the 125kbps long distance mode, but the distance was not up to the ideal state, the deviation was very big.The specification says the sensitivity is up to -103 dBm.Or is this mode only available under Bluetooth support.

And a distance from my CRC test did not pass, or in the movement, CRC check also did not pass, serious interference.Unable to communicate properly.

How to use 2.4G radio normally and make it transmit data stably?

This is a problem that has been bothering me for a long time!!!!

Thanks and Best regards.

Ellison

[Dmitry]

Hi,

there are too many factors that affect distance. What's the size of your packets? Are you testing outdoors or indoors, are there wifi stations nearby? Is it a 52833 DK or some third-party module? Is your power source clean? Finally, did you check whether channel 7 has not too much noise in nRF-Connect RSSI viewer?

As Simon mentioned, Coded PHY doesn't increase sensitivity at physical layer (it's the same 1Mbps bitstream), it uses a FEC encoder that helps to recover from one-two-bit errors (weak signal) but doesn't help much if there's a strong interference on the channel. If you need a stable audio transmission in a noisy environment, maybe it's better to use 1M or even 2M PHY with short packets and some error correction scheme over a larger transmission window.