Automatic coupling of audio signals from an analog network to a digital network

Abstract From the Canadian patent

In a digital cellular communications network calls to and from a fax machine , or, other data equipment coupled to a digital phone require special encoding circuitry. Calls to and from a fax machine or other data device using amplitude and/or phase, modulated tones can be handled more efficiently by monitoring such incoming calls for, the presence of audio control tones. Upon the detection of such tones appropriate, encoding circuitry is automatically switched in to properly encode/decode data tones so, as to permit the automatic transmission of data over a wireless cellular network using, CDMA, TDMA or other digital protocols.