Transmit power is restricted by a number of factors:
- Regulatory (depends on country, channel, antenna gain, etc.)
- Capabilities of the hardware (radio). This is typically a limit in the conducted power per radio chain. The EIRP power limit includes MIMO gain (for example, 3dB for a 2x2 radio), antenna gain, etc.
- ARM limit or manual setting
The actual limit is the minimum of all of these..