Field Strength Calculation
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: | |
| Distance: | Meters |
| V/m | |
| W/m2 | |
Formula:
* All calculations are based on free space conditions (impedance of 377 ohm)
Required Amplifier Power
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: | |
| Distance: | Meters |
| Watts | |
Formula:
* All calculations are based on free space conditions (impedance of 377 ohm)
Required Antenna Gain
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:
* All calculations are based on free space conditions (impedance of 377 ohm)
download:
Field Intensity Calculations
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.
View our other RF Conversion formula sheets:
Useful formulas for RF related conversions
Magnetic field conversions
dBm to Volts to Watts conversion
VSWR Calculations
Product Showcase
Double Ridge Guide Horn Antenna
SAS-570
- 170 MHz to 3 GHz
- Precision machined, Rugged Construction
- High Power Input Capability
High gain, low VSWR, input handling capability up to 800 watts CW, and rugged design make this horn antenna excellent for both immunity and emissions testing.
Contact Details
A.H. Systems, inc.
9710 Cozycroft Ave.
Chatsworth, CA 91311
P: (818) 998-0223
F: (818) 998-6892
E: Email
Additional Resource
Antenna Beamwidth Coverage Calculations
This tool will calculate the maximum coverage that the antenna will cover from a specified distance and antenna's half-power beamwidth. [more...]