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US 4,425,640 AGranted
Telecommunications switching network using digital switching modules
AssigneePlessey Incorporated
InventorsAlexander S. Philip, Thomas S. Maddern
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AssigneePlessey Incorporated
InventorsAlexander S. Philip, Thomas S. Maddern
Estimating the term…
It has been proposed to base advanced Digital Switching networks on a modular array using Digital Switch Modules (DSM). It has been found, for large traffic handling Digital switching systems, that the cross-office delay encountered in multi-stage networks based on 8.times.8 Digital Switching Modules (DSM's) is unacceptably large. To maintain the flexibility provided by the multi-stage concepts a demultiplexing/mixing/remultiplexing stage (DMR) is introduced to replace intermediate DSM ranks. The DMR is used to provide a preset time/space switching function within the total trunking providing the availability of a controlled stage but without the control and delay penalties associated with a fully flexible DSM or the control and link blocking disadvantages associated with a pure space switch. The DMR effectively acts as a pre-programmed or counter driven DSM. By adjusting the degree of DMR function it is possible to provide a very wide range of switch sizes which uses a common organization in the controlled switch stages. The operation of the DMR may be defined in conjuction with a mirror imaging correlation function to provide a constant switch loop delay for duplex connections.
A time division multiplex channel redistribution device having n input paths and n output paths for connection in n interstage links of a multi-stage telecommunication switching network which handles time division multiplexed communication paths and uses digital switching modules, wherein the device comprises n multiplexors (MUX1-MUX8) each having one output and n inputs (A-H), each multiplexor providing one discrete output path (1-8) for the device and wherein each input path (1-8) is connected to a respective input of each multiplexor, said multiplexors being adapted to be controlled to connect a selected input path to a corresponding output path in accordance with address information fed to the multiplexors from a cyclic address generator (CAG) in the device, said cyclic address generator being pre-programmed with a fixed channel allocation address pattern arranged such that the channels on each input path are distributed equally over the output paths without changing the position of the channels within a multiplexed frame.
A time division multiplex channel redistribution device having n input paths and n output paths for connection in n interstage links of a multi-stage telecommunication switching network which handles time division multiplexed communication paths and uses digital switching modules, wherein the device comprises n multiplexors each having one output and n inputs (A-H), each said multiplexor providing one discrete output path (1-8) for the device and wherein each input device (1-8) is connected to a respective input of each multiplexor, said multiplexors being adapted to be controlled to connect a selected input path to a corresponding output path in accordance with address information fed to the multiplexors from a cyclic address generator (CAG) in the device, said cyclic address generator being pre-programmed with one of a number of selectable channel allocation patterns.
Dependencies are inferred from the claim text.