[net.dcom] Digital Voice via Dial-up Circuits

newton2@ucbtopaz.CC.Berkeley.ARPA (10/31/84)

I need information for "digital voice" systems-- means for digitizing
voice for transmission over telecom channels at << 64Kbits/sec. The 
idea is to achieve sufficient data compression to allow transmission
over dial-up circuits using presently available modem technology. I've
not seen any straight compression schemes (DPCM, ADM, etc) which get
the bit rate down quite far enough, so I'm assuming that linear
predictive coding or some similar analysis-synthesis scheme is the only 
way to go. Can anyone supply pointers to info on this, available hardware,
hard numbers on bit rate, brief description of voice quality obtainable,
etc. etc. ??

	Thanks much--

	Doug Maisel (ucbvax!ucbtopaz!newton2)