AFC Power Modes

Outdoor APs supporting the 6 GHz spectrum operate in Standard Power mode only.

Indoor APs supporting the 6 GHz spectrum can operate in one of two different power modes:

  • Low power indoor (LPI) operation
  • Standard power (SP) operation

Types of 6 GHz Devices

Low Power Indoor

Low Power Indoor (LPI) operation is specific to indoor access points operating in the 6 GHz spectrum. LPI mode limits these indoor APs to a maximum equivalent isotropic radiated power (EIRP) of 30 dBm and a maximum power spectral density (PSD) of 5 dBm/MHz. These APs can operate on all four 6 GHz frequency bands (U-NII-5 through U-NII-8) without the use of AFC.

Low Power Indoor Devices

Standard Power

Standard power (SP) operation is applicable to both indoor and outdoor APs in the 6 GHz spectrum, specifically within the U-NII-5 and U-NII-7 sub-bands. When AFC is enabled, these APs are allowed to operate at a higher power, with a maximum EIRP of 36 dBm and a maximum PSD of 23 dBm/MHz. Outdoor APs may only operate in Standard Power mode.

Standard Power Devices

Effective Isotropic Radiated Power

Effective Isotropic Radiated Power (EIRP) is a measure of the output power radiated from an ideal isotropic antenna in a single direction. It is used to quantify the maximum amount of power that could be radiated from an antenna, considering its antenna gain and the transmitter power of the RF system. EIRP is commonly measured in decibel-milliwatts (dBm).

Low Power Indoor vs Standard Power Modes for APs​

Power Modes Max EIRP Max PSD Does it require AFC Indoor or Outdoor Note
Low Power Indoor ​(LPI) 30 dBm 5 dBm/MHz No Only indoor​ Maximum EIRP increases with Bandwidth​

Standard Power​ (SP)

 36 dBm 23 dBm/MHz Yes Both indoor and outdoor Maximum EIRP stays constant with Bandwidth​

Maximum EIRP for Various Bandwidths

  Power Mode EIRP 20 MHz 40 MHz 80 MHz 160 MHz 320 MHz
Access Point Standard Power Max EIRP 36 dBm
SNR Penalty due to increase in noise floor compared to 20 MHz - 3 dB​ 6 dB 9 dB 12 dB
Low Power Max EIRP 18 dBm 21 dBm 24 dBm 27 dBm 30 dBm
SNR Penalty due to increase in noise floor compared to 20 MHz 0 dB
Client Standard Power Max EIRP 30dBm
SNR Penalty due to increase in noise floor compared to 20 MHz - 3 dB 6 dB 9 dB 12 dB
Low Power Max EIRP 12 dBm 15 dBm 18 dBm 21 dBm 24 dBm
SNR Penalty due to increase in noise floor compared to 20 MHz 0 dB

Limitations

Limitations in Standard Power Usage:

  • Client devices operating in the 160 MHz bandwidths are limited to an EIRP of 21 dBm (125 mW).
  • Client devices operating in the 320 MHz bandwidths are limited to an EIRP of 24 dBm (251 mW).
  • Fixed client devices may not emit more than 21 dBm at an angle greater than 30° relative to the horizon. Refer to Limitations in Standard Power Usage for a visual representation.

Limitations in Standard Power Usage

Usage Prohibition of 6 GHz band

The use of the 6 GHz band is prohibited in certain areas, such as oil platforms, automobiles, trains, and aircraft. However, large aircrafts flying above 10,000 feet can utilize APs operating in the 5925-6425 MHz band (for example: U-NII-5 radio band).

Usage Prohibition

Parent topic: Automated Frequency Coordination System