DE1954187C3 - Time division multiplex system - Google Patents

Description

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The invention relates to a time division multiplex system, in which a lot of data, each with a different transmission band or information content are pulse code modulated, in which this data is multiplexed in an in accordance with the transmission band or information content of this data beforehand fixed order are multiple switched, in which a control signal for demultiplexing the individual Data is transmitted by means of a common line that goes to the common transmit the control signals for this data is adapted.

The invention is based on the object of a particularly economical and versatile time division multiplex system to realize.

This object is achieved according to the invention on the basis of a time division multiplex system of the type described in the introduction solved in that the transmission line or the transmission band used is changed by the multiplexing means in accordance with the traffic of this data and that a control signal for this changeover operation is provided by the common line will.

In an embodiment of the invention, it is advantageous when the transmission of information is switched on from the previously used transmission line to a new transmission line this transfer of information on both the previous and the new selected transmission line to is continued at least at the time when all the necessary preparations have been made at the reception desk to receive the data over this new transmission line.

The time division multiplex system according to the invention is for the transmission of various information signals such as audio frequency signals, various data signals, Video signals and frequency division multiplex signals, which differ in terms of their transmission frequency bands, Differentiate between transmission rates, required transmission method, etc. In this Time division multiplexing systems are the transmission line selection and control systems with regard to shared line signaling specially closely linked to the switch and multiplex stages, so that the transmission bandwidth is as good as the conversion system with regard to the required transmission bandwidth and the method of transmission of the input information can be changed.

A pulse code modulation IPCMJ transmission system, in which an input information signal is converted into a digital pulse code for relay transmission purposes is converted, generates a peculiar quantization noise that is dependent on the coding accuracy in the encoding process of the input information. This PCM transmission system has one extremely wide area of application, because relay transmission mostly depends on the accumulation of noise and distortion, transmission loss, accumulation of distortion in the frequency characteristics as well as free from variations in transmission loss and frequency characteristics is what is used in the previously envisaged systems, such as a frequency multiplex amplitude modulation system (FDM). If this is the case, the PCM system can provide a high level of stable transmission Offer quality. Hence it is not only for multiplex transmission by means of a matched twisted pair Cables, like a cable for speech, in which the crosstalk is relatively large and in what noise and level fluctuation exists, but also for super multiplex, broadband and long distance transmission suitable by means of coaxial cables, millimeter waves or light transmission systems.

In the transmission of analog signals, such as voice signals according to the PCM system, the amplitude of an input signal is first sampled and converted into a pulse amplitude modulated (PAM) signal by a sampling pulse with a pulse repetition rate of more than twice the frequency bandwidth of the signal information, which is usually used for sampling the telephony voice 8 kHz used. If necessary, after the time division multiplex conversion, a coder is used in which the PAM signal is converted into a PCM signal of certain coded bits for particular samples. In this example, companded coding is used to ensure a uniform signal-to-noise ratio (encoded signal-to-noise ratio) over a wide range of the operating level of a long-range signal, such as a telephone voice signal. Taking this companding method into account, the result is a logarithmic companding of μ · ■ = ■ 100, where u is a companding parameter. In the event that this companded coding is provided, a maximum of 7 to 8 code elements as the number of bits required for coding the relevant sample values are necessary and sufficient.

be appropriate.

On the other hand, a linear code suitable for image signals is assumed to be 6 to 7 bits considered to be sufficient as the number of code bits required for coding each sample will. Hence, the technique of the PCM system has been recognized as a high-performance and stable multiplex system used for the transmission of analog signals such as voice and video signals. Yes even one 24-channel time-division multiplex PCM system using voice-matched twisted-pair cable has been developed on on a commercial basis as an economic multiplex system for use with connecting lines for short-distance telephone exchanges. Further, development efforts have been made strongly to establish a switching capacity PCM system to offer which is advantageously used with a basic line transmission network in which the degree of multiplexity is large. ao

Although the PCM system has been developed primarily as a relay transmission system in which an analog signal is converted into digital signal by an Codierprozcß cm, its relay transmission line is also in fact a Synchrondigital- ^a 5 transmission line. This means that if the properties of such a transmission line are used, a highly effective multiplex transmission, both very efficient and economical, can be provided for every pseudo-digital signal and the like such as a 2-Pigel baseband data signal, if appropriate conversion and multiplexity is used.

Since, however, in other words, the limit of the equivalent transmission speed per Voice channel in the best case 4.8 KB (kilo baud) with the high-speed data transmission practiced up to now has been according to an amplitude modulation or phase modulation system the transmission capacity as high as 64 KB for one- 4 <> Nen equivalent voice channel according to the data transmission system using a PCM transmission line. As for asynchronous data signals, the transmission speed is over 10 KB per equivalent speech signal achievable when a multiplex conversion system for simple sampling is needed while a transfer of as high as approximately 20KB is possible when the timeline coiling system is used for multiplex conversion.

In addition, a PCM message transmission system was used discovered that in the multiplex transmission of the aforementioned voice and video signals as well as the pseudo-digital signals, such as data signals, the maximum possible transmission bandwidth or the maximum transmission speed of an input data signal through the Sampling rate and the method of transmission of the coding system (co-expanded coding, time axis coding etc.) is set. So it is determined by the number of code bits used and the fact that a defined dependency between these and the transmission speed of a digital, there is a signal transmitted over the transmission line.

If the sampling rate is S , the number of code digits for each channel is Q , F is the auxiliary digits required for hierarchical and separation purposes, and N represents the number of multiplex channels, the bit rate of the transmission line is given by the following:

C = S (NQ + F) (1)

Therefore, although parameters such as 5 and Q, which are necessary for the transmission of different information signals, are not generally the same, it is possible to realize the sharing of a transmission line or the mixed transmission of different kinds of information when the values of N and F can be changed appropriately. At the same time, the transmission bandwidth and the mode of transmission of information can be changed without affecting the transmission line by changing the sampling rate as well as the number of bits if the mutual relationship between the aforementioned parameters is kept appropriate. Furthermore, in the multiplex transmission of information by the time-division multiplex PCM system, the switchover to branching or introduction of a data signal can be effected by simply changing the phase of the clock pulses synchronized with the main information transmission line. This forms an important property of the system since the switchover can be effected by externally applied control action.

The public intelligence networks hitherto used were mainly for the purpose the transmission of telephone voice signals and the hierarchical construction was both for local as well as remote multiplexed transmission networks on the basis of the transmission bandwidth applied to telephone messages (4 kHz). Next, these multiplexing arrangements are general for the included input information. In addition, services for the transmission of other than Speech, such as telegraphic transmission and the transmission of high-speed data signals, by converting the signals to voice frequency signals using an appropriate modulation system executed. Furthermore, there was never any channel switching at the hierarchical levels concerned of a transmission network in response to the variations in message traffic or the types thereof News attempted, albeit manual or automatic, channel switching caused by distress alerts on rare occasions when malfunctions have occurred or maintenance and testing carried out, carried out and, on rarer occasions, additional equipment installed to meet the growing need for ducts.

However, a new development in the field of information activities made a change from previously used message service based on voice frequency telephony to a message service, suitable for the transmission of various data signals from input-output circuits too a central process unit as well as for video messaging services, for documentary messages, Video secretary service and subscriber television service, etc., necessary.

It goes without saying that installing a relatively permanent individual transmission network for each of the different types of information is extremely uneconomical, especially with regard to communications. Thus creates the present

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Invention an economical and versatile time multiplexing information signals is adapted. For tiplex system, which is the characteristic features of multiplexing of PCM pulse groups, for a PCM system in the transmission of this the synchronization of asynchronous PCM signals uses numerous types of information, lnsbc- on the basis of "bit-at-a." -time “multiplexing special is an economical and versatile system 5 like redundant bit codestuffing a pulse“ stuffing ”- the operation of a transmission network. In the figure is representative band, whereby a transmission line discussed information signals especially in the PCM multiplexer / ,,, Z ^ etc. input connections for the above transmission network. T ₁₁ , T ₁₂ , etc. representation and circuit system according to the common ¹⁰ sent encoding terminal offices for the information line signal system with the conversion signals in which input signals are sampled, processed and coded in multiplex stages of the input information signal in time division multiplexing. M ₁₂ , and with the higher hierarchical levels on M ₂₃ etc. denote PCM multiplex synchronizers that are converted and multiplexed in this way for the multiplex synchronization of the PCM signal-PCM signals. At the same time are the '5 group. K ₁ , K ₂ , etc., regenerators for the re-common line signals are used in such a way that the information is multiplexed together according to the type and class of the PCM signal group captured. A "> .V _2, and so are the information on the baseband information levels Toggle change of the PCM multiplex arrangement adapted ordered is at implementing multiplex stages of the concentration and switch ports. By baseband signal, the sampling rate and the number ^20, this is the branching., The Infiltration and the routing of code bits according to the content of the information is achieved. Their construction is always changed. The occupied by the change in the sampling rate common at the time of their installation or expansion and the number of code bits are determined.

Channels are switched to unused channels. In the hierarchical structure described above

Multiplex levels of the PCM signals is the connection ^a 5 PCM multiplex transmission is the signal information, the PCM signal group to a higher multiple - if necessary, the time division multiplexing on converted group or transmission line to "word-at-a-time" basis with the Sampling and coding combined in response to their new calling levels and is thus converted into a lower multiplexed PCM signal influenced during the switching. For a higher MuI-PCM group to an unoccupied group, in order to meet the requirements of a hierarchical system with the traffic requirements for the various information, pulse “stuffing” multiplex synchronization. In the present invention, a stable time division multiplex system is provided for the multiplexity of the PCM group with different training, orders, that is the arrangements M ₁₂ , M ₂₂ , etc., with synchronous switching as well as double must to satisfy the transmission of the different parallel transmission after said switching through which messages are determined taking into account the switching of the occupied channels or PCM group to the channels unoccupied for the types of input signal messages is effected if the switching is required (based on the number of occurrences in order to meet the traffic demand at the various bits contained), the direction of demand, etc., different multiplex conversion stages through the A proposed plan for multiplexing shared line signaling system to satisfy 40 of X _u X ₁ , X ₃ , etc. recommends the voice multiplexity gen. of 24, 120 , 480 and 1440 and a bit frequency of

Using exemplary embodiments, the range is approximately 1.6 MHz, 8 MHz, 32 MHz and 96 MHz. Finding explained in more detail below. The corresponding input information is 24-

Fig. 1 shows a hierarchical implementation with one and 120-channel voice frequency signals for Z ₁₁ and Z ₂₂ multiplex arrangements for different information 45; for Z ₁₂ eight 50 KB data channels, two 250 KB signals that are in a PCM transmission network data channels or one 500 KB data channel. Can be used for Z _23; Video signals in the 500 kHz or 1 MHz band. For Z ₂₃

2 and 3 show the construction and the loading of FDM supergroup _{signals, for Z 32} FDM "master drove a time division multiplex system with variable band group" signals and for Z ₂₃ or Z ₂₄ standard video according to the present invention, which uses a Ge 50 gnale. With appropriate selection of parameters in the common line signaling system concerns; Equation (1) above can use the PCM signal bit fre

Fig. 4 shows the arrangement of branching, sequences at Λ ",, .Y ₂ etc. to these information signals coupling and circuitry which are adapted in the system.

is used according to FIGS. 2 and 3; Figures 2a to c show the principles of a time

FIG. 5 shows an embodiment of the time division multiplex system with variable band according to FIG

plex systems with variable tape according to the present invention by means of a time overview, wah

the invention, which provides a multiplex transmission, in FIG. 3 an example of the PCM multiplex arrangement

concerns different data signals; tion can be seen in which the time division multiplex system

Fig. 6 shows another embodiment of the variable belt according to the present invention;

present invention, seen for hybrid multiplex 60. In the arrangement of FIG. 3 there is

transmission of speech and various data coding and multiplexing of the input

suitable is; formation signals by means of a hierarchical

Fig. 7 shows a time chart of the PCM multiplex system caused by the arrangement from Zeitwori

according to Fig. 6 used information signals. Multiplex operation and coding and pulse »stuffing

1 shows an exemplary embodiment of a synchronization and multiplexing operation based on "bit-at-i"

The typical PCM multiplex arrangement is based on a time-time basis, as is the case with PCM multiplex arrangement

multiplcx PCM transmission network, which is the case for voltages according to FIG.

the implementation and the multiplexing of different In this figure, EX represents a Umse

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Trigger switches at the input information signal samples usually cause serious difficulties

step. X _x , X ₁ etc. do not represent conversion switches, since such a loss in the transmission

at the PCM group signal level. In general, the transmission of a video signal can be undesirable,

a mechanical contact switch is used, this is particularly true for data signal transmission

although it is also a fast electronic switch, 5 at which the loss of information

wcnn necessary for high frequency or broadband is desired, although it could be a single bit

signals can be used. For X _x , X ₁ etc. Accordingly, the present invention draws syn-

a fast switch, as it is considered in digital gate switch- chrone dual parallel transmission, so that

is contained arranged in a matrix, the switching of an information signal of an occupied

are needed because this type of switch is well suited ^for periods of time without any loss of information

net as a conversion switch for digital signals and can be effected. Fig. 2 c shows the principles that

The same is true. this transmission system. In part (1) a layer is

These conversion switches EX and X _x , X ₂ , etc. are shown in which a new requirement is made. It

all adapted in such a way that they are due to the information but occupied time segments i in the sought

controlled by a common line signal »5 time segments, while in part (2) free segments;

represented by CA ₁ , MD _n , MD _n . When requested to switch, the dual

etc. and CD _n , CD ₁₂ etc. represent scanning and parallel transmission of the information P occupied

Multiplex circuits or coding circuits. M ₁₂ , over a certain frame period (kT) by means of the

M ₂₃ etc. denote PCM multiplex synchronizers. Periods of time ι and / made. The transmission

The sampling and coding clock frequencies, as well as the ²⁰ generation through the time segments ι is then stopped,

Phases of MD _n , MD _n etc. as well as the phase when switching to the free time segments

of the multiplex _{synchronization clock for Ai 12} , M ₂₃ by the prescribed switching operations on the

etc. are also, if necessary, completed on the receiving side and the transmission

information from the common line signal on the way of the time slots; takes place alone,

controlled. ^a5 The dual parallel transmission of the frame K

2a, 2b and 2c show by means of a time corresponds here with that for the transfer of a

planes the principles for changing the data control signal through shared line signal

transmission rate or bandwidth with different sizing between the sending and receiving

Time division multiplex coding levels and at the time division multiplex sides or between the connected branched

_s t _u f _en 3 ° pages required time taking into account ci-

2a shows a PCM frame arrangement of a delay in the manipulation and that for the

finally m X η number of time segments. The effect of an exchange between the ι and j

special time segments show, for example, ka time segment transmissions required time. the

sews or word slots that each the not- y slot transmission is generally after

maneuverable number of bits for MD _n , MD _n etc. and 35 of a certain amount of time, the previously set

Contained CD _n , CD ₁₂ , etc. while it is set on the other- conditions stopped or after a

the time periods for the PCM groups signal on the sending side by the communal

show signals that consist of one or more bits for the shaft signal line from the receiving side.

Multiplex synchronization of the PCM group signals is received back, indicating that the receiving

exist. F represents a period of time which 4 ° side has completed the required operation

the information regarding the synchronization and and now is ready.

of multiplexing from the basic frame and an- The time periods i and j do not need here

contains their control information. Tnm denotes to be identical and can be any of the given

be a period of the number of time segments from η X m , which in the same system by a

ten existing basic framework. Tm denotes the «higher number of grouped channels accepted

Frame period, when the frame of m time-out.

cuts is made. In this way the relationship exists. Returning to FIG. 3 the operation of the previous

hung Tm = Tmn / n. lying invention explained below. In this

Except that, as inFig. 2b and 2cge-figure, the arriving at the connections O ₁ to O _n

shows a call for the transmission of information 5 ° incoming information signals according to type and class of the

at the rate (MTm) instead of the usual rate of information separated in such a way that speech signals, both

(l / Tmn) has been made, in the first time segment, for example, broadband data of the order up to heraul

or in the (Km + l; K = l, ..., n -I) time segment, and at 500 KB to connections 11 and 12 and to MD ,

Assume that the (m + 1) time slot is occupied, and MD _{12 are} applied. On the other side «

the information from the (m + l) time segment 55 is FDM supergroup signals or video signal «

switched to any unoccupied channel. within the range from 500 kHz to 1 MHz durcl

Then the ( Km + 1) time segment is applied in its connection 13 to MD ₂ ^ and standard remote

put state and the input sides of (Km + 1) sehsignale and corresponding are through the An

Time segment with the exception of the (Km + 1) time termination 14 applied to MD _3x . The separation of the In

Section which is called is documented so that the information on type and class is based on EX

communication transmission service at a rate so determined by the control signal from the communal Si

as quickly as η times the rate at that time, signal line offered as described above. How ti

can be. It should be noted here that the alternation shown in Fig. 3 is one thing in common

Let there be a control circuit receiving a change signal from an occupied period of time

ren unoccupied time segment without any loss of signal receiving circuit SR, a register um

Information must be carried out. setter RTR, a marker MK etc. SR is at dl ·

When transmitting a voice signal and received signals adapted to the terminal TR

In other words, the loss of various agreements and the register converter is excluded

709 622/105

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to distinguish the received signals and to be sent back.

classify, as well as to control the marker MK- From the above it is clear that when Wech

Ren. The marker MK generates control signals, which be the transmission rate and coding characteristics

before the implementation of the signal information when ver and when checking the connection when different

different coding and multiplex levels of both the 5 your levels of PCM multiple conversion

PCM coding synchronization circuits as well as effective and flexible utilization of the circuit rea

their control actions, such as changing the data.

transfer rate according to the input information, verur- Fig. 4 shows an arrangement according to the present

things. The control signals from the marker MK the invention, in which a main line in the

perform the usual control action in a cross- ¹⁰ time division multiplex system with variable band branching

Rail switch (crossbar switch) and cause and coupled. In the figure, SCOh represents

the separation of the information according to type and class a coupling circuit on the receiver side

at EX. RSEP an isolating circuit. y _n , J ₂₂ , y ₃₃ and y ₄₄ be

Of the central controller through the data drawing especially an input and an Ausganj transmission circuits and similarly EMP ¹ S SCOM and an input and output prior captured signals include identification signals RSEP in / order of the multiplex PCM main one, on to Type and class, the required line. The SCOM side of the figure shows how multi-transfer rate and mode of operation relate; For example pU: x-PCM signal groups of the j order signals that can be coupled again for certain time segments and the RSEP page shows how to identify which time segments in which ²⁰ these signal groups are separated and regenerated PCM multiplex levels must be used and can be returned in the original / order multiplex other for time division multiplex transmission with va- PCM signal groups. control signals necessary for the belt. The voltages applied at the input terminal Z ₁₁ Multi-

These information identification and transmission PCM signal groups are converted into PCM pulse trains.

Line identification signals are set by SR ² 5 , which are multiplexed PCM-

received, stored in RTR , where they are sorted by type and main line by means of a transmission section

Information can be classified, and at MK in ak- from a Z- to j- order PCM-Muitiplexsyn-

tuelle control pulses for marked channels, chronisierer Mi) (S) synchronized and then into the

Implementation systems and time segments at different- time segments of the main line are inserted, as is

which levels of implementation and multiplexity are around 3 ° by the coupling represented by AND ₂

puts. circuit is determined.

It should be noted earlier that part of the information- The synchronizer Mi) (S) is a transmission

identification control signals, which the MK-ausmittel, which a pulse "stuffing" function and

pass, checked O "has to connect the clocks from the main entrance line Z ₁₁ through

special information signals to the corresponding 35 a sampling circuit Γ / Λί, sampled and regenerated

converting circuits MD _n , MD _n , etc. will be generated. A synchronization circuit SYN ₁ and

The circuit connection from EB to a digit pulse generator DG is then used to generate the

Register converter RTR on its connections advises to supply the setting of the multiplex outputs,

and it then becomes the central controller after the phase and pulse rate of the output of the digital

Conversion into a joint line signal, 40 pulse generators are controlled by control signals from the

if necessary, transferred. The remaining in-common line signals are checked,

formationsident'fizierungssignale are on MD ₁ , the common line (control) signals, the

MD ₂₂ and CD _n , CD ₂₂ applied to the conversion received by the signal receiving circuit SR

rate, coding characteristics, number of code bits and are used to identify type and

to determine otherwise. In this example, a part 45 class of signal information is required information

the signals determining the time segments also, include tion, arrive at connection Z. your

if necessary, on MD _n , MD ₂₂ etc. and CD _n , required transformation method (transfer rate,

CD ₂₂ etc. applied to the switching to other un- coding characteristics etc.) as well as the information

occupied channels of any occupied channels - with regard to the selection of voice channels and time

len to control what is the subject of the influence 50 sections are stored in the register converter RTR

the change in the conversion rate, coding chatter. According to the classification by type of information

raktenstik, etc., as described above. tion they are updated by the marker MK

The remaining time segment-determining Si control signals converted to the output rate signals are applied to X ₁ , X ₂ etc. and M ₁₂ , M ₂₃ etc. (pulse repetition rate) and the phase (the designation for various conversion and multiplexing of the 55 Periods of time that are to be exchanged) of the fen multiplex PCM signals of the lower order of the digit pulse generator DG ₁ . To switch the encoded and multiply converted information remaining control signals from the output of the Margnale to higher channel time segments and to connect kierers MK , as in connection with above. At the same time, the occupied times are described with Fig. 3, used to synchronize the sections affected by the controlled (or designated conversion rate of the lower-group multiplex networks) multiplex PCM signals , Multiplex PCM signal converting their unoccupied periods or unoccupied circuits and multiplex encoders switched in co-periods of another system. The slope with the time periods to control conditions of the thus-connected channel portions the receiving signal separation circuit RSEP or multiplex PCM Signalzeitabschmtte comparable at 6 ₅ operates just opposite to that secreted by SCOM stages are m register converter overall such that it from the; ' Multiplex PCM main line saves and after the conversion into the separate and regenerates the Z Multiplex PCM group shared line signals to the central controller pensignale, which are temporarily transferred to the main line.

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are coupled, form the given time periods under Control of the shared line signal.

The sampling circuit, synchronizing circuit and digit pulse generator of RSEP shown in Fig. 4 mainly perform the same function as those of their equivalents on the transmission side. By deriving the setting information from the main line J ₃₃ , the Digitpulsgenera-Or, under the control of the marker MK , generates the output of the shared line signal circuit, clocks of a certain pulse rate and phase, which are necessary at a given pulse repetition rate, the previously inserted I ₁₁ To sample multiplex PCM signals and in this way to control the logic circuits in order to separate the desired PCM pulses. The so separated PCM pulse trains are represented by Mi; ( R) , which corresponds to the receiving section of the PCM multiplex synchronizer and here causes the removal of the inserted »stuffing pulses on the transmission side and the jitter suppression. Restored to their original i'-multiplex PCM group _{pulse trains, the I 22} pulse trains are further coupled to the desired lower PCM signal groups by the received section of the lower order PCM signal conversion switch multiplex synchronizer or their original information is under control by the decoder and the demodulator demodulates the common line signals.

These operations at both the sending and receiving sides close the isolation and conversion of the transfer rate and phase (the time intervals of the multiplex PCM trunk line, the insert and are to be separated) in accordance with the amount to be transmitted i multiplexed PCM signal groups one; all are controlled by the common line signaling system.

Further, the dual parallel transmission can be made consistent with those described above, if necessary Operations are applied in such a way that the transfer of information without any Loss of information can be caused.

FIGS. 5 and 6 show an exemplary embodiment of the present invention with regard to the transmission of data signals according to the PCM system, wherein the multiplex transmission of different Types of data signals with different transfer rates by changing the rate and phase of implementation and multiplex clocks can be made equal according to the input data signal traffic.

In contrast to the previously used voice signals, today's data signals count as Input ZAusgangsinformatiOki for example electronic calculators, needed to combine the individual types with only those already existing. They range from the old 50 baud telegraph data to the current 200 baud data, 1200 Baud data, 2400 baud high speed data, and up to 50 KB broadband data. In view of the future development of data traffic, the ways and means of use electronic computers that want to provide a wide range of areas will even become one greater choice of data signals over multiplex transmission lines be transmitted. However, the hierarchical system is based as in the previous one Telefo never needed a transmission system on the 4 kHz band and makes of the available Circuits only rigid and inflexible use. So it is ineffective for the aforementioned purposes and it would not be an easy matter to provide an economical and high quality service.

On the other hand, rtas provides a time division multiplex system variable band according to the present invention provides a highly efficient and versatile messaging system by changing the transmission capacity of the circuit in accordance with the scope (Rate and performance) and the traffic of the input data to be transmitted.

FIG. 5 shows an example in which data with η TcIcform messages are transmitted as a maximum over the PCM multiplex transmission line. In the

^J 5 figure represent / ,, / ₂ , / "data input terminals. LO ₁ , LG ₂ ... LG _n represent logic conversion circuits which are provided for each channel in order to convert general asynchronous data signals into synchronous PCM signals. CONV represents a conversion circuit for converting the multiplexed PCM signal pulses into bipolar pulse trains paired with the transmission line. IL ₀ represents the PCM output to a line or higher multiplex circuit. CLG represents a basic clock generator circuit required for conversion and multiplexing purposes. MTX is a clock switch circuit which is controlled by the control signals of a shared trunk circuit and generally consists of a matrix circuit.

In general there are two systems of PCM transmission for asynchronous two-level data signals. 1. a simple multiplex transmission system from Pulse signals that are sampled by PCM clocks. as can be seen in Fig. 6, and 2. a multiplex transmission system, in which the changing points of the data signals and their states, either "1" or "0", are coded.

Implementation takes place in one of the two systems

4 "from the input data into synchronous PCM pulse trains by means of simple gate and logic memory circuits which are arranged in each channel, and the maximum transfer rate for data signals depends on the rate of the clocks, which the logic conversion circuits LG ₁ to LG _{n of} the respective Control channels.

FIG. 7 shows the waveforms at the output D ₁ , D ₂ , D _{n of} the basic clock generator CLG, as shown in FIG. Each clock is generated in sequence with a phase difference of I / n to the base period. These basic clocks are used for the clock switch circuit and they are under the control of the shared line signal switching unit in clocks CWP ₁ , CHP _{1 ....} CWP _n implemented, of which:

each has a rate and phase as they are for the signal conversion in the relevant channels are required to set up the logical conversion circuits in these Control channels.

A matrix circuit, as shown as MTX in Fig. Ί, can be used for such a clock switch circuit.

S ₁₁ ... S _n represents switches, each of which has a storage capacity of η times η and is controlled by a code signal called CDS and a channel separation signal called CHSLS .

Both the code signal CDS and the channel selection signal CHSLS are indicated by the mark

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MfC is supplied to the common line signal circuit. This CDS signal determines the input data transfer rate and the time segments of the included channels. It usually consists of η numbers of codes and is applied to the terminals 1, 2, ... η in such a way that the switches in the matrix row of a terminal to which the CHSLS signal is applied are set to the same coded state. For example, if it is desired to switch CHP _x such that it has a rate n / m times the rate of the base clock, then 1, 0, ... 0, 1, 0, ... 0, 1, 0, ... 0 codes at the CDS connections of 1, 2, ... m, m + 1, m + 2, ... 2m, 2m + 1 ... one and at the same time a set pulse is applied to PO, 1 connection from CHSLS. So S _n ... S _{nl are} set to the previously mentioned coded states and a clock is generated at CHP ^ which has a rate nlm times the rate of the base clock D ₁ .

In this example, if the sections m, Im, ... η (m-1) / m include occupied sections, these occupied sections will be switched to other time sections beforehand. In other words, the switching is made for the m-th channel sections c. This means, if the m-th channel sections are occupied with the basic rate and the (m -1) channel sections are unoccupied, that the clock Dm-I of the (m -1) time sections is added to CHP _m by adding the clock Dm of the m Time segments and the information of the channel m is transmitted simultaneously for a certain time period over m and (m -1) time segments. After a certain time has elapsed or after a signal has been received from the receiving side by means of a switch detection line signal, the transmission of the m-th channel information is stopped by the m-th time segments and thus the transmission of the first channel information of said rate, which n / m times the base rate

has started.

In this connection, at the time the transmission of the information is to be alternated with the m-th time segments with the (m-1) note segments, and the change between control clocks Dm and 1 Dm-I is generally consistent by choosing a time by _t ; leads which will not prevent the decoding of the information, although it relies on the information conversion system.

In addition 7 sheets of drawings

Claims (2)

Patent claims: 1. Time division multiplex system, in which a lot of data with a different transmission band or Information content are pulse code modulated, in which this data by multiplexing means in a predetermined in accordance with the transmission band or information content of this data Order are multiple switched, in which a control signal for demultiplexing the individual data is transmitted by means of a common line leading to the common Transmitting the control signals for this data is adapted, characterized in that that the used transmission line or the used transmission band through the multiplexing means is switched in accordance with the traffic of these data, and that a control signal for this changeover operation is supplied by the common line will. 2. Time division multiplex system according to claim 1, characterized in that the circuits Transfer of information from the previously used transmission line to a new one Transmission line this transmission of information both over the earlier and over the new selected transmission line continues until at least the time when all necessary Preparations are made on the receiving end in order to receive the data on this new Receive transmission line.