What you observed is result of country-specific regulations, one of regulated thing is EIRP (which is Tx power + antenna gain). And limits indeed vary with frequency.
Power (both Tx and Rx) is shown in dBm ... that's logarithmic value, relative to 1mW (that's what the 'm' says). It's based on logarithm with base 10 and numbers are in "tenths" (that's what 'd' as 'deci' says). Being logarithmic, value 10dB means factor of 10, 20dB means factor of 100, -10dB means factor of 1/10 (or 0.1). Etc.
You can always check the regulatory limits, observed by ROS, by running command /interface/wifi/radio/reg-info country="United Kingdom" number=0 ... my Audience says that in lower part of 5GHz band (5170MHz-5330MHz) max allowed Tx power is 23dBm (200mW) while in upper part (5490MHz-5710MHz) allowed power is 30dBm (1000mW=1W) ... but comes with other strings attached. Mind that these values are EIRP.
Power (both Tx and Rx) is shown in dBm ... that's logarithmic value, relative to 1mW (that's what the 'm' says). It's based on logarithm with base 10 and numbers are in "tenths" (that's what 'd' as 'deci' says). Being logarithmic, value 10dB means factor of 10, 20dB means factor of 100, -10dB means factor of 1/10 (or 0.1). Etc.
You can always check the regulatory limits, observed by ROS, by running command /interface/wifi/radio/reg-info country="United Kingdom" number=0 ... my Audience says that in lower part of 5GHz band (5170MHz-5330MHz) max allowed Tx power is 23dBm (200mW) while in upper part (5490MHz-5710MHz) allowed power is 30dBm (1000mW=1W) ... but comes with other strings attached. Mind that these values are EIRP.
Statistics: Posted by mkx — Fri Jan 12, 2024 9:03 pm