Title :
The effect of low-pass filtering of the digital frequencies in quantized speech
Author :
O´Brien, Edward M. ; Pogue, David J.
Author_Institution :
Bioeng. Program, Texas A&M Univ., College Station, TX, USA
Abstract :
Monosyllabic words were sampled (time-quantized) at a rate of 20 kHz. The signal was then converted into a trilevel waveform, that is, amplitude-quantized to either a 5 V, -5V, or a 0 V (squelch) level. Digital low-pass filtering was accomplished by reducing any positive or negative wave to 0 V if it has N or fewer quantizing intervals (50 mu s) in it. The effects of three low-pass filtering conditions (N equal to 1, 2, and 3) were compared to those of no filtering. The percentage of words correctly perceived was 29% for the no-filtering condition and 21%, 15%, and 9%, respectively for N=1, 2, and 3.<>
Keywords :
digital filters; filtering and prediction theory; low-pass filters; speech analysis and processing; -5.0 V; 5.0 V; low-pass filtering; monosyllabic words; quantisation; quantized speech; trilevel waveform;
Conference_Titel :
Engineering in Medicine and Biology Society, 1988. Proceedings of the Annual International Conference of the IEEE
Conference_Location :
New Orleans, LA, USA
Print_ISBN :
0-7803-0785-2
DOI :
10.1109/IEMBS.1988.94746
