Increasing the system gain in the EIRP limits regions


In regions with EIRP limits both at the AP and the SM, does the use of a reflector at the SM increase the system gain?

If yes, so it will be equally in both directions in one direction only?


It will increase Link Budget only in the downlink direction.

As an example consider the 5.4 GHz Band for the FCC. EIRP is limited to 30dBm for both AP and SM.

For the downlink with the standard AP sector antenna of 18dBi, Tx Power is turned down to 12dBm. (18 + 12 = 30)

For the uplink with an integrated SM antenna of 9dBi, Tx Power is turned down to 21dBm. (9 + 21 = 30)

When you add a reflector AND you enter the additonal gain of 16dBi into the GUI of the SM then the SM backs off its power by 16dB.

The Link Budget in the downlink is: AP_EIRP(30dBm) - FreeSpacePathLoss + SMAntennaGain(25dBi).

The Link Budget in the uplink is: SM_EIRP(30dBm) - FreeSpacePathLoss + APAntennaGain(17dBi).

The Link Budget in the uplink stays the same as long as you enter the additional antenna gain in the SM. It increases by 16dB on the downlink though.

(If you user does not enter the additional gain into the GUI of the SM then the radio will not know that it needs to turn down its power. In this case there will be a 16dB gain in both the downlink and uplink, but the user will be operating illegally.)

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