Browse Prior Art Database

Adjustment of Speech Sampling Rate

IP.com Disclosure Number: IPCOM000073424D
Original Publication Date: 1970-Dec-01
Included in the Prior Art Database: 2005-Feb-22
Document File: 2 page(s) / 47K

Publishing Venue

IBM

Related People

Clapper, GL: AUTHOR

Abstract

In word recognition systems, it is desirable to sample words at varying time intervals so that rapidly varying segments are not missed but only minimum sampling is done on sustained tones. The system shown provides for a dynamic adjustment of the time base sampling rate as a smoothed function of frequency changes in a spoken word, with the adjustment being linear at slower sampling rates but tapering off to a maximum at higher rates.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 58% of the total text.

Page 1 of 2

Adjustment of Speech Sampling Rate

In word recognition systems, it is desirable to sample words at varying time intervals so that rapidly varying segments are not missed but only minimum sampling is done on sustained tones. The system shown provides for a dynamic adjustment of the time base sampling rate as a smoothed function of frequency changes in a spoken word, with the adjustment being linear at slower sampling rates but tapering off to a maximum at higher rates.

A voiced input on terminal 1 is filtered into frequency bands in frequency analyzer 2 and the separated frequencies are sent over lines 3 to a storage matrix 4. A time base 5 will intermittently sample the lines 3 into storage 4 to enable later recognition of the spoken input. The signals on the lower frequency ones of the lines 3 are supplied to a transition detector 6 which will supply a pulse on its output line 7 for each start of a frequency signal on the connected lines 3. A voltage generator 8 is responsive to these pulses to generate an output voltage on its lead 9 to control the repetition rate of a multi-vibrator 10 which sets the sampling rate of time base 5.

Voltage generator 8 is a type of known stored charge circuit but provides an additional charge drain so that the stored charge will leak off after a period. Input pulses on line 7 from the transition detector 6 are applied through a resistor 11 to the base of an NPN emitter-follower transistor 12 which will conduct to apply a positive...