Nonsinusoidal Circuits

What is a nonsinusoidal waveform?

Any waveform that differs from the basic description of the sinusoidal waveform is referred to as nonsinusoidal. The most obvious and familiar are the dc, square-wave, triangular, sawtooth, and rectified waveforms of Fig. 1.
Fig. 1: Common nonsinusoidal waveforms: (a) dc; (b) square-wave; (c) triangular; (d) sawtooth; (e) rectified.
The output of many electrical and electronic devices will be nonsinusoidal, even though the applied signal may be purely sinusoidal.
Fig. 2: Half-wave rectifier producing a nonsinusoidal waveform.

Example of a nonsinusoidal network

For example, the network of Fig. 2 employs a diode to clip off the negative portion of the applied signal in a process called half-wave rectification, which is used in the development of dc levels from a sinusoidal input. You will find in your electronics courses that the diode is similar to a mechanical switch, but it is different because it can conduct current in only one direction. The output waveform is definitely nonsinusoidal, but note that it has the same period as the applied signal and matches the input for half the period.