Source: wikibot/higher-order-sinusoidal-input-describing-function

= Higher-order sinusoidal input describing function
{wiki=Higher-order_sinusoidal_input_describing_function}

The Higher-order sinusoidal input describing function is a concept from control theory and nonlinear systems analysis. It extends the idea of the describing function, which is a method used to analyze nonlinear systems using harmonic balance. The basic idea behind the describing function is that a nonlinear system's response to sinusoidal inputs can be approximated in the frequency domain.