Given AP1 transmits at 20 dBm, antenna gain of 7 dBi, and a 3 dB cable loss, what is the calculated EIRP?

Given AP1 transmits at 20 dBm, antenna gain of 7 dBi, and a 3 dB cable loss, what is the calculated EIRP?

• A. 2dBm
• B. 8dBm
• C. 22dBm
• D. 24dBm

Answer: (D)

EIRP tells you how much power is effectively radiated in the main direction, combining the transmitter power, the antenna’s gain, and any losses in the feed line. To get it, add the transmitter power in dBm, add the antenna gain in dBi, and subtract any cable or feed losses in dB. Here: 20 dBm transmitted power + 7 dBi antenna gain − 3 dB cable loss = 24 dBm. So the calculated EIRP is 24 dBm (about 251 mW). The +7 dB from the antenna boosts the effective radiated power, while the 3 dB loss reduces it, yielding a net +4 dB over the original 20 dBm.

EIRP tells you how much power is effectively radiated in the main direction, combining the transmitter power, the antenna’s gain, and any losses in the feed line. To get it, add the transmitter power in dBm, add the antenna gain in dBi, and subtract any cable or feed losses in dB.

Here: 20 dBm transmitted power + 7 dBi antenna gain − 3 dB cable loss = 24 dBm. So the calculated EIRP is 24 dBm (about 251 mW). The +7 dB from the antenna boosts the effective radiated power, while the 3 dB loss reduces it, yielding a net +4 dB over the original 20 dBm.