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Question 2

A WLAN transmitter that emits a 50 mW signal is connected to a cable with 3 dB loss. If the cable is connected to an antenna with 9dBi gain, what is the EIRP at the antenna element?

    Correct Answer: A

    To calculate EIRP (Effective Isotropic Radiated Power), we need to convert the transmitter power from mW to dBm first. The formula to convert mW to dBm is: 10 * log10(mW). For 50 mW, the conversion is 10 * log10(50) = 16.99, which is approximately 17 dBm. Next, we account for the cable loss of 3 dB: 17 dBm - 3 dB = 14 dBm. Finally, we add the antenna gain of 9 dB: 14 dBm + 9 dB = 23 dBm. Therefore, the EIRP at the antenna element is 23 dBm.

Discussion
buckOption: A

CONVERT 50mW = (17dB) -3dB + 9dB = 23

EjikmanOption: A

Wrong. Correct answer is 23 dBm https://www.everythingrf.com/rf-calculators/eirp-effective-isotropic-radiated-power https://www.rapidtables.com/convert/power/mW_to_dBm.html

CoolbreezeOption: A

The correct answer is 23.