Abstract: A multiplexing communication system for combining several asynchronous digital signals 151, 156 into a single high-speed line 141 comprising synchronizing circuits 101, 106 on each on n input data lines, service information insertion circuits 180 on each of the n synchronized lines, an nBmB coder 130 utilizing a pulse stuffing circuit 170 for increasing the n synchronized signals to m synchronized signals, and a multiplexer 140 for converting the m synchronized signals into a single high speed output 141.

Abstract: A digital transmission system employing nBmB codes in which provision is made for insertion of service and auxiliary data bits. The transmitter of the transmission system includes a series to parallel converter, register file, pulse insertion circuit, nBmB encoder and parallel to series converter. The bit rate of the parallel n bit code streams is converted to produce an additional time slot after each occurrence of a predetermined number of data bits. Service and auxiliary data bits are inserted in the additional time slots. The receiver portion of the transmission system includes a series to parallel converter, followed by an nBmB decoder, a pulse separator, a register file and a parallel to series converter. At the receiver, the mB code is converted back to an nB code from which the service and auxiliary data bits are extracted and subsequently removed.