Harmonic Distortion

Harmonic distortion is a measure of the amount of power contained in the harmonics of a fundamental signal. Harmonic distortion is inherent to devices and systems that possess nonlinear characteristics—the more nonlinear the device, the greater its harmonic distortion.

Harmonic distortion can be expressed as a power ratio or as a percentage ratio. Use the following formula to express it as a power ratio:

PHD=Pfund−Pharm(dbc)

where

  • P HD is the power of the harmonic distortion in dBc
  • P fund is the fundamental signal power in dB or dBm
  • P harm is the power of the harmonic or interest in dB or dBm

Convert power to voltage and use the following equation to express harmonic distortion as a percentage ratio:

Percentage⁢ of⁢ Distortion⁢=VharmVfund×100%

Related Topics

Total Harmonic Distortion