DATA TRANSMISSION OVER MOBILE RADIO VOICE CHANNEL WITHOUT INTERFERENCE TO SPEECH TRANSMITTED ON SAME CHANNEL

摘要

A radiotelephone system provides a voice channel for carrying voice signals between a mobile unit and a called or calling unit. A first modem in the mobile unit and a second modem connected to a point along the voice channel employ a "blank-and-burst" method of communication to provide a data channel between a first data device connected to the mobile unit and a second data device connected to the second modem. The data channel enables the data devices to communicate with each other seemingly concurrently, and with minimal interference, with the voice signals that are being carried over the voice channel and without requiring modifications to any base station.