Power (dBm) to Field Strength (dBuV/m)

This calculator converts Power in dBm at a receiver input to Field Intensity deciBels-microVolt-Per-Meter (dBuV/m) at the antenna.

The tool is useful when a measurement is made using a calibrated spectrum analyzer or receiver (in dBm) with an antenna connected to its input port. It provides the field strength in dBuV/m at the antenna.

This tool requires as input

• Power at the input to the receiver (dBm)
• Impedance (ohm)
• Antenna gain (dBi)
• Frequency of operation (Hz)

Formula

AF = 20*Log₁₀(9.73/(λ√G))

V_dBμV = P_dBm + 10*Log₁₀(Z) + 90

E_dBμV/m = V_dBμV + AF_dB/m

Example Calculation

For

• Input power of -60 dBm,
• Input impedance of 50 ohm,
• Antenna gain of 3 dBi,
• Frequency = 1000 MHz

The field intensity is calculated to be 74.25 dBuV/m.

Related Calculators

• dBm to V/m
• V/m to dBm