| 摘要 |
1417709 Data transmission; exchanges PLESSEY CO Ltd 11 Sept 1973 [15 Sept 1972] 42830/72 Headings H4K K1U1 and K1M9 In a two way time division multiplex switching exchange serving a plurality of incoming and outgoing time division multiplex channels each connected to terminating circuits, the exchange incorporating a time division channel switching network including a plurality of incoming highways and an equal plurality of outgoing highways arranged in pairs and each pair carrying corresponding incoming and outgoing channels respectively of a group of exchange terminating circuits in the same synchronous character interleaved multiplex time-slot-appearance order and a plurality of time switching cord locations with each exchange terminated circuit served by the exchange being continually selectively allocated a time switching cord location, such as is disclosed in Specification 1417557, each of said incoming and outgoing highway pairs EHA is provided with a duplicate highway pair EHDA the phase of the incoming and outgoing highway pairs EHA being displaced by a determined duration with respect to the multiplexes on the duplicate highway pairs EHDA, e.g. for one channel duration time. The exchange receives a number of TDM two way transmission systems, e.g. ITS1/OTS1 each terminated on switching interfaces TSIE 1 connected with a set of time switching cords C1 each including a time switch TS and a set of control registers CR carrying information relevant to the channel, and providing storage for channel status information cross point address and transfer address. Exchange highways EHA are each duplicated i.e. EHDA which is phase displaced by, say, one channel delay. A multiple of this delay but less than one frame in total may however be employed. The phase difference so introduced results in the provision of two possible zero delay interconnecting paths between like channels of two highways. |
