Blank and Burst Transmission of Data Over Active Speech Channels.

Cellular communications systems transmit control information over active voice channels by blanking out the analog speech signal for several milliseconds and sending a burst of digital data. The effect is perceived as a click which is unobtrusive provided it occurs infrequently. To increase the capacity of this type of data transmission, we explore the application of a speech segment reconstruction technique. The transmitter selects a blanking interval on the basis of a segment classification measure. The receiver replaces the missing speech with an estimate based on prior received speech. We estimate that this approach will allow the transmission of five 16 ms data bursts per second without degrading speech quality. Conventional blank and burst transmission becomes annoying when the intervals between data bursts are shorter than several seconds.