The long-term period measurement, an instrumental method in phoniatry.

With the help of an Analog to Digital Converter we are able to perform serial and statistical analysis in the time domain. The difficulty in those long-term period measurements consists in the correct extraction of the periodicity in human voice. A simple method is the electroglottography, which, however, is not applicable in all cases. The analysis of the acoustic wave (translated via microphone) demands a lot of electronics if to be precise. Our investigation consists of a compromise between precision and amount of instrumentation, and we only took one parameter as a criterion. The possible error is negligible. We present the results of this measurement type using the patterns of one normal voice and eight different kinds of voice disorders.