CONFIG_OPENTHREAD_DEFAULT_TX_POWER Usage and Effects

[Woobin Song]

Hi Noridic team,

I have enabled Matter over Thread on the nRF5340. In this setup, I'm planning to reduce the TX power by setting CONFIG_OPENTHREAD_DEFAULT_TX_POWER=0. Apart from transmission power and current consumption, does this setting affect anything else?
I am currently using NCS version 2.6.2, and the default value of CONFIG_OPENTHREAD_DEFAULT_TX_POWER is 3.

config OPENTHREAD_DEFAULT_TX_POWER
    default 20 if MPSL_FEM
    default 3 if SOC_SERIES_NRF53X
    default 8 if SOC_SERIES_NRF52X

BR,

Woobin

[Woobin Song]

Hi Noridc team,

Could you provide an official response from the Nordic team?

[Jørgen Holmefjord]

Hi,

Changing CONFIG_OPENTHREAD_DEFAULT_TX_POWER is the correct way setting TX output power for the Thread protocol, see Changing TX power for Thread.

Apart from the obvious change in range and power consumption, it should not affect anything else. It will only change the radio TX power for the OpenThread protocol.

Note that TXPOWER above 0dBm requires the radio to run in high voltage mode, so this will be requested if TX power is set above 0dBm.

Best regards,
Jørgen