GB916781A - Method and arrangement for the identification of speech - Google Patents

Abstract

916,781. Recognising speech sounds. STANDARD TELEPHONES & CABLES Ltd. July 3, 1959 [July 10, 1958], No. 22926/59. Class 106 (1). In apparatus for recognising speech sounds the speech signals after compression is applied to four band-pass filters F1, F2, F2,3 and F3, each of which has a wide band width and the output of each filter is applied to a detector D which produces a pulse when the signal changes polarity to start a pulse generator J, the counter C serving to count the pulses until the next pulse, the output of the counter, representing the instantaneous wavelength of the filter output signal, being entered into a shift register SH. A recognition circuit TR connected to the shift register stages produces outputs on leads L representative of the sounds detected. The detector D may produce signals of both polarity transitions. The output pulse appears on leads 1, 2 and 3. The first starts the generator J, the third opens the gates G to pass the contents of the counter into the three parallel shift registers and the pulse on line 2 resets the counter in preparation for the next cycle. Entry into the shift registers may be made at each cycle or only when the contents of the counter differ from the previous value.