Real-time Vocoder Hardware: Past, Present And Future

The design of hardware which implements real-time analysis/synthesis telephony (commonly referred to as VOCODER's) has been heavily influenced by the prevailing limits of electronic technology. The current explosion of capability made possible by LST techniques is once again changing the way the game is played. This paper traces this evolutionary process through the current state of the art -- the bipolar "bit-slice" microcomputer approach -- and suggest some ways in which future signal-processing systems may be implemented.