nRF52840 bitrate in long range PHY and Rx sensitivity

[Chaabane]

Hello,

I'm using the nRF52840 development kit with the "« ble_app_att_mtu_throughput" example with version s140 6.0.0-6alpha.

What's the bitrate used in the long range PHY ? if it's 500 kbps, is there a way to change it to 125 kbps to get more range ?

Also, can the RX sensitivity be changed ?

Thank you Chaabane

[Sigurd]

Hi,

What's the bitrate used in the long range PHY ? if it's 500 kbps, is there a way to change it to 125 kbps to get more range ?

When we are using "CODED PHY" we are using 125kbps BLE mode (S=8 coding scheme). This is the BLE mode that will give you the longest range.

Also, can the RX sensitivity be changed ?

The RX sensitivity in 125kbps BLE mode is -103 dBm. The sensitivity depends on the BLE mode, and with 125kbps BLE mode it is fixed to -103 dBm. See this page.

[Sigurd]

If you are trying to increase the range even more, try to use the function sd_ble_gap_tx_power_set to increase the radio's transmit power. The default value is 0 dBm, but it can be increased further if needed.

[Chaabane]

Thank you Sigurd, That's what I though.

I'm using 9dBm as transmit power.