In telecommunication, a time-assignment speech interpolation (TASI) was an analog technique used on certain long transmission links to increase voice-transmission capacity.
TASI worked by switching additional users onto any channel temporarily idled because an original user has stopped speaking. When the original user resumes speaking, that user would, in turn, be switched to any channel that happened to be idle. The speech detector function is called voice activity detection.
One of the issues with using this type of technology was that the users listening on an idled channel can sometimes hear the conversation that has been switched onto it. Generally the sound heard was of very low volume and individual words are not distinguishable. See also crosstalk for a similar phenomenon in telecommunications.
TASI was invented by Bell Labs in the early 1960s to increase the capacity of transatlantic telephone cables. It was one of their first applications requiring electronic switching of voice circuits.
Later Digital Circuit Multiplication Equipment included TASI as a feature, not as distinct hardware.
Famous quotes containing the word speech:
“If we would enjoy the most intimate society with that in each of us which is without, or above, being spoken to, we must not only be silent, but commonly so far apart bodily that we cannot possibly hear each other’s voice in any case. Referred to this standard, speech is for the convenience of those who are hard of hearing; but there are many fine things which we cannot say if we have to shout.”
—Henry David Thoreau (1817–1862)