Variable time delay and bit rate speech communication on ATM networks

There are some new demands on speech processing when voice communication is carried out over ATM networks. This paper discusses some problems of speech coding and transmission on ATM networks. We propose two schemes for speech processing, which have variable transmission delay and bit rate respectively, to reach at the goals: small assembly delay, high transmission efficiency and toll speech quality. We transmit different speech cells in different time intervals and define a new "distribution entropy" to classify different input signals. We then design a new speech codec in the second scheme whose bit rate is perceptual importance based. It has better speech quality than that of the G.727 system.