Title:
【発明の名称】パルス符号変調デジタル自動ブランチ交換局
Document Type and Number:
Japanese Patent JPS59501730
Kind Code:
A
Abstract:
A pulse code modulated digital automatic exchange for a telephone network or other communication network has a multiplicity of N input/output ports connected to an input/output system comprising a plurality of multiplexers that each scan a small group of ports in a predetermined cycle; output signals from the multiplexers are converted into M-bit parallel digital data signals and recorded in an input data store at a location identified with the port of origin. The input data store is scanned, by a fully bused synchronous transfer system, in accordance with a predetermined transfer time cycle having at least N fixed transfer time slots, one for each communication port; during the transfer time slot for any port, data recorded in the input store from that port is transferred, via an M-digit parallel data bus, to a location in an output data store associated with another port for which that data is destined. From the output store the data signals are supplied to a reverse converter and then to de-multiplexers, all part of the input/output system, connected back to the input/output ports. Sequence control circuits control the timing of operations within the transfer system to correlate the transfer of data, during a call between any two ports, so that the transfer time slot for each port in a given call becomes the input time slot for that port and the output time slot for the other port. Hook switch information, tone data, port identification data, and all other control information is bused throughout the transfer system of the exchange. For networks in which data is already in digital form, the conversion stages may be required to translate from serial to parallel form or from one digital format to another, as contrasted with the analog-to-digital conversion required for audio circuits. The input and output stores may be combined in a unified input/output store.
Inventors:
Bratu Dowa-S William T
Application Number:
JP50285583A
Publication Date:
October 11, 1984
Filing Date:
August 15, 1983
Export Citation:
Assignee:
Brad Douce, William Te.
Scary Lithia-de-El
Scary Lithia-de-El
International Classes:
H03K17/00; H04J3/02; H04Q3/58; H04Q11/04; (IPC1-7): H04Q3/58; H04Q11/04
Attorney, Agent or Firm:
Masao Okabe