Wi-Fi EIRP Calculator

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As a Wi-Fi engineer, there are a number of occasions when it is useful to understand the EIRP ("Effective Isotropically Radiated Power) of a system. (I'll leave to you to read this Wikipedia link for an EIRP explanation). This is often a requirement when using external antennas on an access point or perhaps using tools (e.g. survey software) which require you to account for the various gains and losses in a system.

Calculating EIRP is crucial to understand the power level that will actually end up radiating out of your antenna. This is often for reasons of regulatory compliance, coverage considerations or perhaps matching the power of client devices.

As this is something I seem to have to do on a fairly regular basis, I thought I'd knock up an EIRP calculator to add to my website .

To calculate the EIRP of a system, enter the AP transmit power, the loss of any cable and connectors  and the gain of the antenna. Note that if you are using an AP with an internal antenna, you can leave the cable loss at 0dB. Finally, hit the 'Calc' button to see the EIRP of the system in expressed in dBm and mW:




Tx Power: Cable Loss: (dB) Antenna Gain (dBi):

Calculated EIRP: ---- (dBm) / --- (mW)



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Check out my other RF calculators: link

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