## Is ERP the same as EIRP?

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So ERP and EIRP are measures of radiated power that can compare different combinations of transmitters and antennas on an equal basis. In spite of the names, ERP and EIRP do not measure transmitter power, or total power radiated by the antenna, they are just a measure of signal strength along the main lobe.

### What is the relationship between EIRP and antenna gain?

EIRP combines the power of the transmitting antenna and its gain. EIRP is expressed as the product of the power of the transmitting antenna and its gain. Pt is the power of the transmitting antenna and Gt is the gain of the transmitting antenna.

**What is ERP in antenna gain?**

Effective Radiated Power or ERP is the power supplied to an antenna multiplied by the antenna gain in a given direction relative to the gain of a half-wave dipole antenna in that same direction.

**What is EIRP used for?**

Most often conveyed as either decibels (dB), or decibels over isotropic (dBi), EIRP is used to gauge the maximum possible radiation from an RF system, either for standards purposes or for specification. With an isotropic radiator, the radiation is emitted as a point source with a spherical radiation pattern.

## How do you calculate ERP?

To calculate ERP, Take the transmitter power output, subtract the losses from the duplexers, subtract any measurable feedline loss and add the antenna gain. Example: (2 dBd combined duplexer and feedline loss) + (5 dBd antenna gain)= 3 dBd gain. Use antenna gain in dBd not dBi.

### How is EIRP calculated in dB?

As an example, suppose the radiated power is measured for an arbitrary antenna. Suppose the peak power is measured at = =90 degrees, and the value is EIRP = 20 dBm = -10 dB = [0.1 W = 100 mW]. Then a perfectly isotropic antenna radiating 20 dBm would produce the same measured power for the peak angles of our antenna.

**What is EIRP formula?**

EIRP Formula : EIRP = PT – LC + Ga. Where, PT = Output power of the transmitter (dBm) LC = Cable loss (dB)

**How is ERP power calculated?**

To calculate ERP, Take the transmitter power output, subtract the losses from the duplexers, subtract any measurable feedline loss and add the antenna gain. Example: (2 dBd combined duplexer and feedline loss) + (5 dBd antenna gain)= 3 dBd gain.

## What is maximum ERP?

(a) Maximum ERP. The ERP of base transmitters must not exceed 100 Watts under any circumstances. The ERP of mobile transmitters must not exceed 60 Watts under any circumstances.

### What is ERP FCC?

Many FCC rule parts specify power and/or emission limits in terms of the transmitter system (transmitter, radiating antenna, and cable connector) effective radiated power (ERP) or equivalent (or effective) isotropically radiated power (EIRP).