Effective Isotropic Radiated Power
Apparent power a transmitter would need if it radiated equally in all directions; combines transmit power, antenna gain and cable loss.
Formula
Variables
Example
10 dBW tx, 15 dBi antenna, 2 dB loss: EIRP = 23 dBW
Did You Know?
A directional antenna does not create energy — it concentrates it, so a modest transmitter behind a high-gain dish can produce an EIRP of thousands of watts along the beam.
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