Equivalent omni-direction radiated power (EIRP)

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What is the effective omni-direction radiation power?

In fact, the directional transmitting antenna is often used, so that the transmitter power is concentrated in a particular direction and the energy is greatly enhanced in this particular direction.
assuming that the energy in a particular direction is greater than the non-directional antenna to enhance the GT times, in this direction equivalent to the transmission power expanded GT times,
transmitter output power and GT product is effective omni-directional radiation power

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EIRP (Effective isotropic radiated power) effective omni-direction radiated power, also known as equivalent omni-direction radiated power (equivalent isotropic radiated power), The power radiated from the satellite and Earth station transmitting antenna in the center axis of the beam is called the effective omni-directional radiated Power (EIRP) of the transmitting device, which is the product of the Power PT of the radio transmitters supply antenna and the absolute gain GT of the antenna in the given direction, which is an important index to characterize the transmitting capability of the Earth station or transponder.
Each party to an ideal omni-direction antenna with the same unity gain, usually as a reference antenna for the wireless communication system. The EIRP is defined as: EIRP=PT*GT, which represents the transmitting power in the maximum antenna gain direction that can be obtained by the transmitter compared to an omni-directional antenna. The PT represents the transmitter power, and the GT represents the antenna gain of the transmitting antenna. If the logarithm (db) is calculated, then: EIRP = P in P–loss +g is the output power (in dbm) of the transmitter, Loss is the feeder loss (in db) between the transmitter output and the antenna feed, and G is the transmit gain (in dbi) of the antenna.

Unit Explanation: dbm: is an absolute value of the test power, calculated as: 10lgP (Power value/1MW), for example, if the transmit power P is 1mw, converted to dBm after 0dBm. The DBI and DBD:DBI and DBD are the values of the test gain (power gain), both of which are a relative value, but the reference datum is not the same. The reference datum of DBI is omni-directional antenna, and the reference datum of dbd is dipole, so the two are slightly different. It is generally believed that the same gain, expressed in dbi, is 2.15 larger than that of DBD. Example 1: For an antenna with a gain of 16dBd, the gain is converted to a unit of DBI, then 18.15dBi (generally ignores the decimal place, is 18dBi). Example 2::0DBD=2.15DBI. The GSM900 antenna gain can be 13dBd (15dBi) and the GSM1800 antenna gain can be 15dBd (17dBi).