Occasional Contributor II


Good evening :
Can anyone tell me what is the meaning of EIRP (I found this parameter in radio profile of outdoor AP 85)

Thanks in advance


Good evening,

EIRP stands for Effective Isotropic Radiated Power

This is a commonly used term in RF engineering circles to describe the amount of RF Power that is emitted to the air.

In general, it is a combination of a Device's Transmit Power (Tx) + Antenna Gain (Gx).
Occasional Contributor II

Re: Eirp

Ok thank you very much:D:D
Occasional Contributor I

A bit more precise definition

More precise ir reads Equivalent isotropically radiated power, and the main idea is to compare different kind of transmitters with different antennas.

This value actually states what would be the power of isotropic (theoretical) radiator to get the same radio energy level in the same point, as with compared antenna and transmitter. This is why EIRP can be quit high with high gain antennas even with low transmitter power.
And it really can be found adding antenna gain to transmit level, as antenna gain is exactly the efficiency ratio in comparison with isotropic reference antenna.
EIRP is limited by regulations (different in different countries), to avoid unbearable interference between different WLAN devices.