A VOICE DETECTOR

摘要

A voice operated switch detects the presence of human speech by comparing the received electrical signals with a delayed version of themselves and assessing the degree of similarity which exists. The received signals are passed to a correlator 4, which compares undelayed signals applied to terminal 3 with delayed signals applied to terminal 5. If the degree of correlation as determined by a level detector exceeds a threshold value applied over terminal 12, a pulse generator 9 controls a switch 10 to enable the speech signals to be transmitted over a communication link 13 to 15. The sensitivity of the voice detector is dependent on three time durations T1, T2 and T3. Typical values of these durations are given.