Environmental Engineering Reference
In-Depth Information
The above equations show reduction of the second and third harmonic
distortion factors with respect to their low-frequency values. Indeed, at
frequencies respectively equal to and the asymptotic diagrams of
and start to linearly decrease. Then, the distortion factors
become constant at the cut-off frequency.
This behaviour is qualitatively
shown in Fig. 7.4.
7.2.2 Closed-loop Amplifiers
Consider now the same feedback amplifier in Fig. 7.2, but where the
transfer functions of blocks
and f are now frequency dependent.
Specifically, let block
be characterised by the frequency-dependent
nonlinear coefficients
and
and denote as
the
transfer function of linear feedback block f, as schematised in Fig. 7.5.
