Control of Telephony Voice Transmission Energy Level (01-Jan-1993)

Control of Telephony Voice Transmission Energy Level

       A design is disclosed for controlling the voice
transmission level on telephony lines.  The benefit of the design is
that a digital voice sample can be recorded into a computer system
and then retransmitted at user-specified energy levels, without
requiring multiple storage copies of the voice sample or off-line
reprocessing of the voice sample.

      In telephone systems, the maximum transmission energy level for
the network is usually specified by the network provider.  Regulation
is necessary to prevent damage to the telephone network and degraded
quality.  In this design, the user is able to specify a desired
transmission energy level.  This specified transmission level is
usually lower than the specified maximum level to provide a buffer
against saturation.

      For a product which transmits digital voice, it is necessary to
adjust the digital representation of the voice such as to not exceed
the allowed transmission energy level for the particular telephone
line.  If a product generates artificial voice, it is simply a matter
of generating voice with the right energy level, but, if a product is
resending voice that has been recorded, either via a telephone call
or via other input such as a microphone, it is necessary to perform
an energy boost or attenuation on the voice before it is transmitted.

      The disclosed design is used in a system which uses digital
signal processors and a host controlling computer to record and/or
send voice messages, originated either by the system or by the
end-user.  Applications include, but are not limited to,
voice-messaging and interactive voice-respons...