Effective radiated power

The Effective Radiated Power ( also effective radiated power, engl. Effective radiated power, ERP or erp ) is the product of the fed in a transmitting antenna power multiplied by the antenna gain ( relative to a half-wave dipole ). If no direction is specified, the value for the main beam direction of the transmitting antenna, the antenna gain is their greatest simultaneously applies. Refers to the antenna gain to the isotropic radiator, then one speaks of EIRP.

• Gd: antenna gain relative to a half-wave dipole (dimensionless)

As a reference antenna for the antenna gain here the half-wave dipole is used. To make the reference antenna in the antenna gain indicated, this is usually given in dBd, said the unit dB trailing " d", or more precisely the half-wave dipole is the reference antenna " dipole ". A half-wave dipole has a gain of 1 (corresponding to 0 dBd ).

As ERP and EIRP differ only in the reference antenna for the antenna gain ( a half-wave dipole has a gain over an isotropic radiator of 1.64 - 2.15 dBi accordingly ), there is the following relationship:

Or exemplified in logarithmic units:

Spellings

ERP is often treated as a physical quantity ( electric power). My hence is assigned to a unit ( watts). Another possibility is ERP to get behind the unit in brackets, eg watts ( ERP).