Untersuchung unperiodischer Zeitvorgänge mit der Autokorrelations- und der Fourieranalyse

Auto-correlation and frequency analyses of a series of aperiodic time events, especially filtered noises and hisses, have been made. The position and band width of the frequency range are best obtained from the frequency analysis but the energies contained in the several bands are most easily obtained from the auto-correlation function.

The mean number of null-points of the time function is estimated from the curvature of the latter function in the vicinity of the null-point and also with the aid of a decimal counter. The second method is found to be more exact.