Fundamental content

The fundamental oscillation content is the proportion of the fundamental oscillation in a signal that is not purely sinusoidal (for example: rectangle, triangle or other). Such signals can be broken down into purely sinusoidal components using Fourier analysis . This frequency spectrum can be obtained, for example, via the Fourier transformation . ${\displaystyle g}$

The fundamental frequency of a signal is defined as:

${\displaystyle g={\frac {I_{S1}}{I_{S}}}={\frac {I_{S1}}{\sqrt {I_{S1}^{2}+I_{S2}^{2}+I_{S3}^{2}+\dots }}}}$

With

• the rms value of the fundamental component of the signal ${\displaystyle I_{S1}}$
• the rms value of all harmonics ${\displaystyle I_{S}}$
  • the current strength (instead, the electrical voltage can also be used for calculation). ${\displaystyle I}$

Connection with the distortion factor  k :

${\displaystyle g={\sqrt {1-k^{2}}}}$

literature

• Thomas Görne: Sound engineering. 1st edition, Carl Hanser Verlag, Leipzig, 2006, ISBN 3-446-40198-9
• Horst Stöcker: Pocket book of physics. 4th edition, Verlag Harry Deutsch, Frankfurt am Main, 2000, ISBN 3-8171-1628-4