Maximum Power Level (dBm) = Allowed EIRP (dBm) – Antenna Gain (dBi) + Cable Loss (dB)
Where: |
Is: |
Maximum Power Level (dBm) |
the highest permissible setting of the Maximum Power Level attribute |
Allowed EIRP (dBm) |
the EIRP limit allowed by the regulations, |
Antenna Gain (dBi) |
the gain of the chosen antenna, |
Cable Loss (dB) |
the loss of the RF cable connecting the AP to the antenna. |
As the 2.4 GHz, 5.4 GHz and 5.8 GHz have an operating bandwidth of 5 MHz, 10 MHz, 20 MHz or 40 MHz then the maximum allowed EIRP depends on the operating bandwidth of the radio as shown in the table below:
Normal EIRP limits with operating channel bandwidth
Operating bandwidth (MHz) |
Allowed EIRP (dBm) at 5.2 GHz |
Allowed EIRP (dBm) at 5.4 GHz |
Allowed EIRP (dBm) at 5.8 GHz |
Allowed EIRP (dBm) at 2.4 GHz |
5, 10, 20, 40 |
24 - 30 |
24 - 30 |
36 |
36 |
The settings to be used for regions with the EIRP limits iare shown below:
Setting maximum transmit power to meet general EIRP limits
Antenna |
Maximum available antenna gain (dBi) |
Operating bandwidth (MHz) |
Transmitter Output Power parameter setting (dBm) |
||||
2.4 GHz |
2.5 GHz |
5.2 GHz |
5.4 GHz |
5.8 GHz |
|||
ePMP 2000 Conn. module Sector antenna |
18 |
5, 10, 20, 40 |
N/A |
N/A |
12 |
12 |
18 |
ePMP 1000 Conn. module Sector antenna |
15 |
5, 10, 20, 40 |
21 |
27 |
15 |
15 |
21 |
Note Calculations are on the basis of 0.5 dB cable loss and the highest gain antennas per size of which Cambium Networks are aware. At these operating frequencies, antenna cable losses even with short cables are unlikely to ever be below 0.5 dB for practical installations and cable diameters. |