Method and apparatus for communicating a plurality of asynchronous

Abstract

Multiple asynchronous signals are transmitted and received through a digital link. Each of a plurality of information signals is digitized at a digitizing rate derived from a component of the signal. For example, the color subcarrier of a television signal can be used to establish the digitizing rate for video and audio signal portions. Each digitized signal is packetized for communication at a transmission rate greater than and asynchronous with its digitizing rate. A variable time interval results between successive transmitted packets for each signal. The time interval between each successive packet for each signal is filled with a variable number of pad bits to provide a continuous data stream. The data streams for all of the signals are multiplexed to provide a combined data stream for transmission. Each packet for each of the signals contains a fixed number of data bits digitized over a fixed time interval related to the digitizing rate for the signal. The transmitted combined data stream is received, and the receipt of successive packets is monitored for each signal to determine the fixed time interval for that signal. The digitizing rate for each signal is computed from its fixed time interval. The received data packets for each signal are then converted to an analog form at the signal's digitizing rate to reconstruct the original information signals.