1987 Volume 28 Issue 3 Pages 145-151
Using computer simulation, the authors examined the theoretically expected discrepancy between obtained H/N ratios and real H/N values, the effects of perturbations of pitch and amplitude on H/N ratio, and other factors.
(1) Taking the averaged wave as an estimate of the harmonic component resulted in harmonic energy greater than its real valus. (2) The H/N ratio method detected perturbations of pitch and amplitude as a quantity of noise energy. The effect of pitch perturbation on the H/N ratio was much greater than that of amplitude perturbation. (3) The error range of the measurement system did not contribute significantly to the calculated H/N ratio.
Based on the above findings, we may predict that the H/N ratio of an imaginative normal voice with a real H/N ratio of 10 dB (F0 160 Hz, pitch perturbation 0.5 %, amplitude perturbation 0.1 dB), for example, is measured as 10.9 dB.
