DE2324279A1 - PROCEDURE FOR EXCHANGE OF INFORMATION IN AN INTEGRATED PCM REMOTE NETWORK - Google Patents

Description

STANDARD ELECTRICAL LORENZ. "Λ

AKTIENGESELLSCHAFT 2 O Z 4 Z / 3

Stuttgart

H.Ruyter et al 5-3-6-11

Procedure for the exchange of information in an integrated PCM telecommunications network.

The present invention relates to a method for exchanging information in an integrated PCM telecommunications network. The use of digital controls and the well-known possibility of also digital voice signals Representing shape by means of PCM technology is already part of the design guided by transmission systems in which both the passing on of the too transmitted information (e.g. language) as well as the forwarding of the Control of the transmission of required signals is done in a digital manner.

Such a transmission system consists, for example, of several incoming or outgoing PCM lines and devices that temporarily store the incoming information in a known manner and bring it to the actual transmission path in the correct cycle or distribute it to the outgoing lines. The requirement of speed transparency for bit streams of a certain transmission speed placed on such a system requires the insertion of additional bits in the bit stream to be transmitted. The information is therefore transmitted asynchronously. The description of such a system and the technical implementation of the insertion of additional bits ("stuff ^11" ) can be found in DOS 2 .121 660.

In the course of the advancing development of PCM switching technology and the The resulting conversion of the transmission stiffeners to this technology is

8.5.1973
FK / Bre

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INSPECT »

H.Ruyter et al 5-3-6-11

it is desirable to have those already existing and in PCM technology operated transmission lines in a future integrated Femmeidenetz with to include the facilities of the transmission line (e.g. amplifier) to be able to continue using the switching technology however, makes different demands than those on which the development of the transmission system was based, in particular a synchronous one is now becoming Information transfer required.

If one compares, for example, an independent PCM transmission system, as described above, with a transmission system in the integrated network that provides the same number of channels and the same information transmission speed is designed, so the use of the transmission link of this system in the Achieve the switching system only with considerable adjustment effort, because the transmission system uses an overall higher transmission speed than for operation due to the transmission of additional bits is necessary between switching parts of an integrated network. A bit stream coming from the exchange that controls the transmission path of the independent transmission system, must also first use this in the facilities (e.g. multiplex facilities, clock adjustment) System are processed and, at the end of the transmission path, the corresponding facilities are reversed before going through the following Exchange can be forwarded. The invention aims to simplify this process; it is characterized in that the PCM transmission links of a one with a certain transmission

transmission speed operated PCM transmission system with unchanged Transmission speed between the PCM exchanges as required be switched so that in the PCM exchanges a number of additional bits are added to the bit stream to be transmitted at predetermined points, and that these additional bits are received in the PCM exchanges at these

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Digits are split off again, the number of additional bits being determined by the difference between the transmission speed of each used PCM transmission path and the switching clock of the integrated PCM telecommunications network is determined.

The method according to the invention thus allows direct, synchronous Information transfer on the existing PCM transmission line; it has another advantage: the transmission path is initially independently operated; The information lines of the transmission system were to be extended at a later time due to the extensive expansion of the integrated network are also included in the integrated telecommunications network, so parts of the equipment of the originally existing transmission system can be removed and possibly used elsewhere become, which is not possible without the method according to the invention.

The invention is illustrated below with reference to one in the drawings Embodiment explained, the numerical data being a 120-channel PCM system is based. Show it:

Fig.l The block diagram of a transmission link, which also between PCM exchanges are used;

2 shows a basic circuit diagram of the additional devices of a PCM exchange;

3 shows an illustration of the processes described.

Fig.l shows the transmission link UeS, which in a known manner Line terminals LE and repeaters R is equipped. The device M of the transmission system (multiplexer, demultiplexer, stuffing logic, Clock adjustment) takes care of the stringing together of the connected PCM lines G incoming information (or their distribution to the outgoing lines G) and the clock-correct information transmission

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with the addition of the additional bits already mentioned. The PCM exchanges VST contain facilities C, which are to be sent out Bitstream add a number of additional bits or split them off again, and the required increase in the transmission speed from 8.192 to 8.448 MBd. The optional switch to Operation between the PCM exchanges is symbolically represented by coupled switches A and B.

FIG. 2 shows the additional facilities C of the exchanges according to FIG the invention. The processing and switching of the received bit stream takes place in the exchange in a known manner.

In the transmission mode, the clock derivation stage TAS receives the switching clock VT of 8.192 MHz and generates an 8.448 MHz transmission clock UeT from it (corresponding to the 8.448 MBd of the transmitted bit stream). A channel counter KZ is thus switched on, which runs from 1 to 132 and is passed on the channel number causes the reading AL of the information in the corresponding line of a voice memory of the exchange. the The increase in the number of channels in the channel counter is proportional to the increase in the transmission speed. Switches the channel counter KZ to certain in A channel number recorded in a channel number memory KNS speaks Comparator VG, which causes the blocking SAL of the reading of information from the voice memory.

In the receiving mode, the arrangement works, apart from the required one Synchronization SYN in a similar way; the transmission clock UeT of 8.448 MHz controls the reading ES of the received bit streams via the channel counter KZ into the voice mailbox of the exchange. If the line counter LZ shows one of the specified channel numbers (i.e. when additional bits arrive),

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the comparator VG thus causes the registered * SES to be blocked and may initiate other switching operations. The relaying of the bit streams can then again be carried out at the switching speed of the integrated network (8,192 MBd).

Fig. 3 shows a possible timing of the arrival of bit streams (line clock LT) and their transmission (transmission clock UeT), where the channel numbers 129, 130, 131, 132 are noted. The bit streams arrive with the line clock LT (3a). The channel counter KZ reaches channel number 129, recording the Bit stream is prevented by the comparator VG (SES). Only when the Channel counter is switched to 1 by the line clock LT, the Bit information of the first channel added to the switch memory. This happens with all channels up to and including channel 128.

The channels are correspondingly in the sending exchange (3b) up to 132 empty channels; while it is their turn, no mediated information is sent out (SAL).

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3 claims

2 sheets of drawings

3 figures

1 List of Reference Numbers

409849/0431

Claims (3)

H.Ruyter et al 5-3-6-11 Patent claims: Method for the exchange of information in an integrated PCM telecommunications network with PCM transmission links between PCM exchanges, characterized in that the PCM transmission links (UeS) of a PCM transmission system (M, UeS, M) operated at a certain transmission rate and with an unchanged transmission rate between the PCM exchanges (VSt) are switched, that in the PCM exchanges a number of additional bits are added to the bit stream to be transmitted at predetermined points, and that these additional bits are split off again when received in the PCM Vermirtlyngsstellen at these points, the number the additional bit is determined by the difference between the transmission speed of the PCM transmission link (UeS) used and the switching cycle of the integrated PCM telecommunications network. 2. The method according to claim 1, characterized in that a transmission rate corresponding to the transmission rate (UeT) is generated in the PCM exchange by devices (C) from the switching cycle (VT) of the integrated telecommunications network, which the reading (transmission mode) or the writing (receiving operation) of the binary information in a voice memory of the PCM exchange controls, with certain, predetermined channel numbers reading or writing is interrupted and additional bits are sent out or split off. 3. Arrangement for performing the method according to claim 2, characterized by a clock derivation stage (TAS) for generating the transmission clock (UeT) from the switching clock (VT), the output of which is connected to the input of a -A 409849/0 4 31 H.Ruyter et al 5-3-6-11 Channel counter (KZ) is connected, the number of channels within a Frame according to the higher transmission rate is greater than the number of useful channels and the output of which is the channel number for voice storage the switching center, and through a comparator (VG), its inputs with a channel number memory (KNS) that contains the channel numbers for which reading or writing is interrupted is to be, and the output of the channel counter (KZ) are connected, and its output signal via the voice memory control the readout or Writing in a voicemail interrupts.