A '''closed-loop transfer function''' in [[control theory]] is a mathematical expression ([[algorithm]]) describing the net result of the effects of a closed ([[feedback]]) [[loop (telecommunication)|loop]] on the input [[signal (information theory)|signal]] to the circuits enclosed by the loop.
== Overview ==
The closed-loop [[transfer function]] is measured at the [[output]]. The output signal [[waveform]] can be calculated from the closed-loop transfer function and the input signal waveform.
An example of a closed-loop transfer function is shown below:
The summing node and the ''G''(''s'') and ''H''(''s'') blocks can all be combined into one block, which would have the following transfer function:
