Below is a calculation tool to help determining the actual field Strength or power density (in V/M) at a given distance with a known antenna gain.

This calculation tool will assist:

• The calculation of field Strength levels required by certain immunity standards.
• Calculating the required power amplifier and antenna combinations for new testing requirements.
• For safety (radiation hazard) or electromagnetic interference (EMI) effects.

Calculation:

Amplifier Power:	Watts
Antenna Gain:	dBi numeric
Distance:	Meters
	V/m
	W/m2

Formula:

This calculation tool to help determining the required power to produce a desired field intensity using antenna gain and separation distance.

Calculation:

Desired V/M:
Antenna Gain:	dBi numeric
Distance:	Meters
	Watts

Formula:

Calculate the required antenna gain using the maximum system power, desired field intensity and separation distance.

Calculation:

Amplifier Power:	Watts
Required Field:	V/m
Distance:	Meters
	dBi

Formula:

Further Reading:

• The "Selecting antenna/power amplifier combinations for the coming new RF immunity standards" article explains different power amplifier / antenna matching combinations for some new RF immunity standards.
• Our Antenna Beamwidth Coverage Calculations is a unique tool to assit in calculating the maximum coverage based on antenna half-power beamwidth.