GB1586818A - Apparatus working with pulse code modulation or similar digitizing techniques and according to the time division multiplexing principle for processing the information of a number of telephone channels - Google Patents

Abstract

The device comprises a plurality of identical individual devices (1a-1d) which are designed for autonomous operation and are interconnected by means of cables (27). Each individual device processes the information from telephone channels by means of pulse code modulation and according to the time-division multiplex principle and has the corresponding components. Telephone lines (26) are connected to the devices (1a-1d) via connection boxes (24). Analog signals which are issued from or fed to telephone devices are input and output via these lines. One of the individual devices (1a) is used as the control device and generates basic clock and sync pulses for all the devices (1a-1d). If the control device (1a) fails, another of the devices takes over its function. <IMAGE>

Description

(54) APPARATUS WORKING WITH PULSE CODE MODULATION OR SIMILAR DIGITIZING TECHNIQUES AND ACCORDING TO THE TIME DIVISION MULTIPLEXING PRINCIPLE FOR PROCESSING THE INFORMATION OF, A NUMBER OF TELEPHONE CHANNELS (71) We, ANSTALT EUROPAISCHE HANDELSGESELLSCHAFT, of Vaduz, Principality of Liechtenstein, a body corporate organised under the Laws of the Principality of Liechtenstein, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement::- The present invention relates to a new and improved construction of apparatus which operates with pulse-code-rnodulation or similar digitizing techniques and according to the time-division multiplexing principle for processing the information contained in a number of telephone channels.

According to the present invention we provide an apparatus working with pulsecoding-modulation or similar digitizing techniques and according to the time-division multiplexing principle for processing information from a number of telephone channels, comprising: a plurality of individual devices designed for automatic operation and connected together to obtain said number of tele phone channels; each individual device operating with pulse-code-modulation or similar ditizing techniques and according to the time division multiplexing principle; Each individual device containing elements required for the independent operation and for processing the information of telephone channels, the number of which is smaller than the required total number of telephone channels;; one of said individual devices being adjustable to provide a master control device which at least generates the base cycle pulses and synchronization pulses for all of said devices; and another device being capable of assuming the control functions upon breakdown of the first mentioned one device initially functioning as a master control device.

The invention will be better understood and objects other than those set forth above, will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein: Figure 1 is a perspeetive view of an individual device working with pulse-codemodulation and according to the timedivision multiplex principle;.

Figure 2 illustrates an apparatus composed of a number of the individual devices shown in Figure 1; and Figure 3 schematically illustrates a circuit diagram for the construction of the apparatus shown in Figure 2.

Detailed description of the prescribed embodiments Describing now the drawings, the device or apparatus 1 illustrated by way of example in Figure 1 will be understood to correspond in construction and mode of operation to the equipment described in our copending patent application No. 50634/77 to which reference -may be readily had and the disclosure of which is incorporated herein by reference. The device or apparatus 1 processes the information from a maximum of 8 telephone channels in standard fashion according to the pulse-codemodulation technique or a similar digitizing process and according to the time-division multiplexing principle.The illustrated device 1 contains all of the elements or components needed for the automatic operation and such components or elements are housed internally of a housing 2, as has been shown and de scabed in the aforementioned copending application. At the front plate 3 of the housing 2 there are arranged the operating elements, terminals and indicator of display lamps.

The front plate 3 possesses a control or operating panel 4 having a number of operating or control elements 5 to 15, each of which coacts with a schematically and not particularly referenced scale. This contrdl panel can be covered by means of a cover 16.

The operating elements 5 to 15 can be actuated by means of a not particularly illustrated key which is'secured to the cover member or cover 16.

By means of the operating or control elements 5 to 15, each of which is associated with a telephone channel, there can be adjusted in each channel, independent of the other channels, one of a number of operating conditions or states.

By means of the operating element 13 there is adjusted or set the number of the device within the connected or switched together group of devices. The device with the device number 1 - assumes the function of a master control device in a manner still to be described hereinafter.

By means of the operating element 14 there is set' or adjusted the number of used channels. The operating element 15 enables setting the bit rate per channel. With the illustrated apparatus the bit rate per channel can be adjusted to, for instance, 16 k bit/s, 32 k bit/s or 64 k bit/s.

Furthermore, at the front plate 3 there are arranged different control lamps 17 and schematically illustrated terminals 18 to 23 at which there can be connected the cables.

As best seven by referring to Figure 2, at the terminal or connection 18 there is connected a terminal box 24 by means of a cabled 25. At this tèrminal or connection box 24 there are connected the telephone lines 26 which are coupled with not particularly illustrated telephone installations. By means of this connection 18 there is accomplished the input and output of analogue signals which are produced by the telephone in stallations and delivered to the telephone installations, respectively.

As also best seen by referring to Figure 2 with the devices la, ib, lc and id connected or switched together, in each case the terminal or connection 19 df the one device is connected by means of a cable 27 with the terminal or connection 20 of the next follow ing device. The terminal 19 of the last device id is connected by means of a cable 28 with a microwave or similar transmission device 29. In the event that the transmission is accomplished by a cable, instead of by means of microwaves, then the terminal 29 of the last device id is connected with such trans mission cable.

At the terminal 21 there is connected a direct-current voltage source, whereas the terminal 22 is connected with an alternating current voltage source. The devices 1 are designed such that breakdown of the alter nating-current voltage supply there is auto matically accomplished a switch-over to the direct-current voltage supply. At the terminal 23 there can be - connected a buzzer or other suitable or equivalent device.

By means of thswitch 30 both of the voltage sources can be cut-in or cut-off. The lamp 31 illuminates when the voltage sources are turned-on. Further, two fuses 32 and 33 are provided for the direct-current voltage source and the alternating-current voltage source respectively.

Now in Figure 2 there is shown an apparatus where for increasing the total number of telephone channels there are switched or connected together a number of similar devices, in the embodiment under discussion four similar devices la, lb, ic and id. Each of these devices la, lb, ic and id is of the same construction or design as the individual device shown in Figure 1. Since each individual device la, ib, ic and id possesses a maximum of eight channels, with the apparatus of Figure 2 the maximum possible number of channels is increased to 32.

The total number of channels is adjusted at each device la, ib, lc and id by means of the operating or control element 14. The device number associated with each individual device is adjusted or set at each device la, ib, ic and id by means of the operating element 13. The device with the device number 1 assumes the master control function. Since all devices la, ib, ic and id are of the same construction, basically each individual device can function as the master control device.

Now in Figure 3 there is schematically illustrated the construction of the interconnected individual devices la, la, ic and id, the device lc having been omitted and as to each such device which has been illustrated there have only been shown the most important components or elements thereof.

Each device la, ib, ic and id possesses a transmitter portion or transmitter and a receiver portion or receiver which is independent of the transmitter. The transmitter of each individual device, among other things, possesses a clock generatdr 35 which is connected with a quartz oscillator 34. This clock generator 35 is operatively connected by means of a driving or driver circuit 36 at a base clock line or conductor 37 which is common for all of the devices. Moreover, each device possesses a multiplexer 38 to which there are delivered the digital pulses of each channel A, B... N. To simplify the showing of the drawing not all of the channels have been illustrated. Now in each channel A, B, . . N there is provided a structural group or assembly 39 which encompasses all of the components or elements which are required for converting the incoming analogue signals into digital pulses according to the pulsecode-modulation or a similar technique.

The multiplexer 38 receives its clock pulses from the clock generator 35. The multiplexer 38 is connected at the output side thereof by means of a driver circuit 40 with a common data line 41 at which there are delivered the digital information pulses which are, interleaved according to the time-division multiplex technique. The bit cycle output of the multiplexer 38 is connected by a driver circuit 42 with a bit cycle line 43. The input and output of the multiplexer 38 for the frame signal FT is connected by means of a driver circuit 44 with a frame signal line 45 The data line 41 and the bit cycle line 43 are connected with a conventional and thus not particularly shown transmission device.

The device assigned the number 1, for instance the device la, functions, as already mentioned, as the master control device.

This control device la produces the base cycle B1 for all of the devices la, ib, lc and ld. This base cycle B1 is delivered by means of the base cycle line 37 to all of the other devices lb, ic, and ld. Now from this base cycle B1 there are derived in each device all of the internally required cycles and pulses.

The master control device la further more produces a frame signal F1 which is transmitted by means of the frame signal line 45 to the other devices ib, lc and ld. The frame signal F1 ensures for synchronous operation of all of the devices la, ib, ic and ld. In the event that there is required in the transmission device a bit cycle T,, then this bit cycle likewise is only produced by the master control device la and delivered to the bit cycle line 43.

Since all of the devices la, ib, ic and ld are controlled by the same base cycle B1 and synchronized with the frame signal FT, thus, as with a single device, the channels of all connected together devices la, ib, le and ld, can be connected with one another in the following manner: First of all all of the channels of the device No. 1, then all of the channels of the device No. 2, then all of the channels of the device No. 3 and so forth.

It is immaterial in this regard in which sequence the devices are numbered. What is important is that one device can be set or adjusted to carry out the functions of a master control device.

The receiver of each device la, lb, lc and ld, among other things, possesses a quartz oscillator 46, a clock generator 47 connected therewith and a demultiplexer 48. The clock generator 47 is connected by means of a respective driver or driving circuit 49 and 50 on the one hand with the bit cycle line 51 coming from the transmission device and, on the other hand, with a base cycle line 52.

The output side of the clock generator 47 additionally is connected with the demultiplexer 48.

The demultiplexer 48 is connected at its input side by moans of a driver or driving circuit 53 with a data line 54 which is coupled with the transmission device and which delivers to the demultiplexer 48 the digital data pulses transmitted by the transmitter.

Each demultiplexer 48 is connected by means of a driver circuit 55 with a frame signalline 56.

At the output side there are connected with the demultiplexer 48 the individual channels Al, B1. .. N1. Each channel possesses a channel structural group or assembly 57 analogous to the transmitter, and which contains all of the components or elements needed for converting the digital pulses into.

analogue signals, in order to obtain an analogue output signal which corresponds to: the corresponding analogue inout signal at the transmitter side.

The device la which operates as the guidance or control device produces, in accordance with the bit cycle TR received by the transmitter side, the base cycle BR for all devices la, ib, lc and ld. This base cycle BR is transmitted by means of the base cycle line 52 to the other devices ib, lc, id. Out of the digital pulses appearing at the data line 53 each device la, lb, ic and ld seeks synchronization pulses, places into operation its receiver frame and after having obtained synchronous running delivers a frame signal FR to the frame signal line 56. In the event that synchronism is not established then there is not produced any frame signal.

All of the devices la, lb, lc and ld receive this frame signal FR and are regulated to a synchronous operation based upon such frame signal. If the synchronization device breaks down at a device, then this does not have any influence upon the remaining functions, since this device then will be synchronized from another device.

All of the demultiplexers 48 operate on the basis of the same base cycle BR and are synchronized to one another by means of the frame signal line 56. The information pulses appearing at the data line 54 are distributed, analogous to multiplexing at the transmitter side as for a single device, properly at the individual channels Al, B1... N1 Since, as mentioned, each device la, ib, ic and id possesses all of the elements or components needed for the automatic operation and with the illustrated stack operation of a number of devices only the master control device carries out all functions, certain of the components of the devices which are not employed as the master control device are not or only incompletely utilized. Nonetheless, it is readily possible at any time to have another one of the devices fulfil the control functions in the event that the master control device has partially or completely broken down. As mentioned, such adaptation of the system can be readily accomplished by simply switching the operating element 13. It is also conceivable to construct the devices such that such switching operation is accomplished automatically.

While there are shown and described present preferred embodiments of the invention, it is to be distinctly understood that the invention is not limited thereto, but may be otherwise variously embodied and practiced within the scope of the following

Claims (4)

claims. WHAT WE CLAIM IS:-

1. An apparatus working with pulsecode-modulation or similar digitizing techniques and according to the time-division multiplexing principle for processing information from a number of telephone channels, comprising: a plurality of individual devices designed for automatic operation and connected together to obtain said number of tele phone channels; each individual device operating with pulse-code-modulation or similar ditizing techniques and according to the time division multiplexing principle; each individual device containing ele ments required for the independent opera tion and for processing the information of telephone channels, the number of which is smaller than the required total number of telephone channels; one of said individual devices being adjustable to provide a master control device which at least generates the base cycle pulses and synchronization pulses for all of said devices; and another device being capable of assuming the control functions upon break down of the first mentioned one device initially functioning as a master control device.

2. The apparatus as defined in claim 1, wherein: all of the individual devices are similarly constructed and each individual device can be employed as a master control device.

3. The apparatus as defined in claim 1, wherein: each device has a front plate at which there is arranged an operating element by means of which the master control device and the sequence of each individual device and the group of connected to gether devices can be adjusted.

4. An apparatus working with pulsecode-modulation or similar digitizing techniques substantially as herein described with reference to the accompanying drawings.