Showing papers on "High-bit-rate digital subscriber line published in 1976"

Pcm time division multiplex communication network with digital subscriber stations

Abstract: A PCM time division multiplex communication network is disclosed having a central processing office and digital subscriber stations. A special code word is prefixed to the PCM data sent by the central processing office to designate the intended subscriber station. While only the designated subscriber station is capable of accepting the PCM data, other subscriber stations are capable of amplifying and passing on the PCM data to the next subscriber station. Specifically, the invention is directed to a method and apparatus for transmitting PCM data wherein no special means are provided in the subscriber stations for synchronization while at the same time no increase in the bandwidth of the transmission signal is necessary. This is accomplished by using the PCM data accepted by a subscriber station as the carrier for the output information of the subscriber station. In addition, the PCM data transmitted from the central processing office is characterized by bits of varying amplitude and width which permit the subscriber stations to derive the timing signal directly from the PCM data.