:Autocorrelation:

Pronunciation GB: ˌɔːtəʊkɒrəˈleɪʃn, GA: ˌɑːt̬oʊkɑrəˈleɪʃn

A signal processing method for estimating the period of periodic portions of the speech pressure waveform. A windowed portion of the waveform is compared to another windowed portion of the same duration, but which starts a little later. A correlation coefficient between the two portions is calculated. The delay of the second window is increased and the process repeated. This process repeats, building a function of the magnitude of the correlation coefficient with respect to the delay. The delay which coincides with the maximum correlation coefficient is then used as an estimate of the period of the waveform in the original window. The original window is then advanced in time and the process starts all over again.