Another solution to this which seems a lot cleaner IMO is to change the antenna gain in the config.json file such that when the system substracts the commanded TX power (coming from the server) with the antenna gain, it finds a valid RF power in the lookup table. So in my case, if I set the antenna gain to 8 dBi, then the server would go and find the parameters corresponding to 20 dBm (which is tx_lut_11): "tx_lut_11": { "pa_gain": 3, "mix_gain": 9, "rf_power": 20, "dig_gain": 0 } This was suggested to me by Tony over on the Chirpstack forum: Thanks Tony!