impulse response function

see also:

IRF, delta-distribution, Dirac delta function, unit impulse function

Impulse response analysis is an important aspect of digital signal processing with regard to the characterization of dynamic systems, such as measurement setups. The impulse response function (IRF) describes the reaction of the dynamic system to an external change. In digital measurement technology, this characterizes the deviation of the output signal for the case that an extremely short impulse is given to the input, whereby the impulse response describes the reaction of the system as a function of time. The so-called „unit impulse function“ has zero width, infinite height and an integral (area) of one. Since it is impossible in practice to generate such a perfect impulse as input for measuring the impulse response, the shortest possible impulse is used to approximate the ideal impulse to determine the impulse response. It is important that the impulse is short enough compared to the measured impulse response so that the result is close to the true impulse response and thus still provides a usable result for assessing a measurement setup.