Abstract: | Since Pulse Code Modulation emerged in 1937, digitized speech has experienced rapid development due to its outstanding voice quality, reliability, robustness and security in communication. But how to reduce channel width without loss of speech quality re-mains a crucial problem in speech coding theory. A new full-duplex digital speech communication system based on the Vocoder of AMBE- 1 000TM and microcontroller ATMEL 89C5 1 is introduced. It shows higher voice quality than current mobile phone system with only a quarter of channel width needed for the latter. The prospective areas in which the system can be applied include satellite communication, IP Phone, virtual meeting and the most important, defence industry. |