Abstract: Data transmission equipment includes a plurality of data stations connected in series through a loop transmission path. A synchronizing station is connected to the data stations in the loop transmission line. The synchronizing station generates transmission signals made up of a synchronizing slot, an address slot and data transmission slots. A display board for setting and displaying data is connected to at least one of the data stations. Process line controllers are connected to data stations to transmit data related to process control to, or receive data from, a process control apparatus. The data transmission equipment further includes sensor bases connected to data stations. Each data station includes a coupling unit connected in series with the loop transmission line, transmitting and receiving units connected to the coupling unit through a bus, input units provided between the transmitting units and the sensor bases, and a bus provided between the transmitting units and the sensor bases.

Abstract: A data communication system allocates use of a common data communication medium shared by a plurality of stations. During each transmission cycle, the communication medium carries data packets of varying priority which each station receives. The stations are allocated use of the communication medium during one or more priority intervals as a function of the priority of the packet which the station is ready to transmit. Each station is synchronized to a transmission cycle period which is divided into subperiods. Certain types of packets are relegated to transmission and reception within predetermined subperiods.

Abstract: In an integrated circuit/packet switching network comprising a plurality of nodes and one or more common access loops for inter-node network, an integrated circuit/packet switching system comprises a fixed time cycle frame format allotted to the loop or loops. Each of the nodes functions in accordance with the frame format to assemble one or more composite packets for each destination node from a plurality of circuit- and packet-switched calls designated to said each destination node and to send the assembled composite packet or packets on the loop or loops for each frame cycle time. Each node also functions in accordance with the frame format to extract self-designated composite packets among composite packets on the loop or loops and to disassemble the extracted composite packets into the constituent circuit- and packet-switched calls.

Abstract: A plurality of stations are used to strip expendable messages from a serial ring communication network. One station uses either the destination address field or the source address field as the basis for removing a portion of the message. Another station uses the status of a control indicia as the basis for removing the remaining portion of the message from the ring. By distributing the stripping function, between multiple stations on the ring, a significant reduction in ring latency is achieved.

Abstract: An asynchronous time division multiplex switching network for switching multi-service communication data performs point-to-point data switching, data switching between a single calling party and a plurality of called parties, and data switching between plural calling parties and a single called party. The network comprises plural incoming and outgoing time division multiplex highways including asynchronous channels each formed by a packet data and an address label (j, k). Incoming and outgoing terminal switching equipments are respectively connected to the incoming and outgoing highways. A bus interconnects the terminal switching equipments. The labels are converted into several sub-words according to the type of communication switching. In response to the values of these sub-words, the outgoing terminal switching equipments accept or do not accept the packets to be transmitted.

Abstract: An exemplary embodiment includes a first binary counter whose counting period corresponds to a block length of a pulse frame, a block counter controlled by the first counter, and a logic element for generating working clock signals, wherein the counters are switchable for employment in different multiplex systems and the logic element gates out the working clock signals for different multiplex systems.

Abstract: The invention provides a ring communication network having an improved error recovery mechanism. The system uses a token or toggle signal which does not have an inherent control value but one that requires the values of a contiguous pair thereof to control access to the transmission medium of the system. A station recognizes that the ring is idle if the present value of the toggle signal is the same as the value of the toggle signal in the previous frame. Conversely, a station recognizes that the ring is busy if the present value of the toggle signal is different from the value of the toggle signal in the previous frame. A station that detects an idle toggle signal and wishes to transmit data on the communication ring changes the value of the toggle signal to that which corresponds to a busy status and transmits its data.

Abstract: An electronic switching system in which digital data is required to be exchanged between two pieces of electronic apparatus such as two telephone subscribers, in which a parallel time division multiplex highway is used to carry the data, the highway being divided into two paths, the data being transferred in both directions during a single time period using the different paths for each direction, identification of the transmitting and receiving parties being by use of two address buses in a single time slot period.

Abstract: In a telephone exchange system comprising information-processing sequential logic systems and devices for averting overloads, the group processor requests which occur for the incoming through-connections are rejected first given a necessity of an overload defense system and with an overload of a first degree, the request being the through-connection request to be executed, respectively, once incoming and once outgoing (with reference to the respectively-employed subscriber line or trunk or, respectively, corresponding channels) over line trunk groups per connection. Requests by group control unit for outgoing through-connections are likewise rejected only given an overload of a second degree. Discrimination of the two overload levels is provided by way of a counter.

Abstract: An adaptive echo canceller for a full duplex transmission system comprises a cascade arrangement of an adaptive digital filter and an automatic gain control device. The AGC device receives the output signal from the adaptive digital filter and delivers the estimate of the echo signal to the receive line for subtraction. It has a multiplier receiving the output signal and a signal representative of the multiplication factor from a gain adaptation circuit. A separate gain change circuit is connected to receive the output signal from the adaptive digital filter and simultaneously modifies the tap coefficients of said filter and the multiplication factor of the AGC device in opposite directions for maintaining the output of the adaptive digital filter in a predetermined range.

Abstract: A frame synchronizing signal insertion system at a transmitting end has a plurality of multiplexers. Frequency-divided frame synchronizing signals are produced by frame pattern generators of the plurality of multiplexers, respectively. These frequency-divided frame synchronizing signals which have different patterns are logic-ORed by a multiplex gate so as to obtain a composite frame pattern. When a composite multiplex signal having the composite frame pattern is transmitted to a receiving end and the composite frame pattern does not match a predetermined pattern, the receiving end can detect a malfunction of any one of the multiplexers at the transmitting end, and transmits an alarm signal or the like to indicate malfunctioning of the corresponding multiplexer.

Abstract: An apparatus is provided for charging memories in a telecommunication exchange which includes line modules (LIM). These have communication paths for communication with terminals and possibly external apparatus, and have a control computer (LPU) for maintaining communication between terminals or between a terminal and external apparatus. The communication between terminals connected to different modules is set up via a digital group selector. To enable writing from a data information source (BS, TS) to all the module control computers in a single process through a module (LIM 1) selected as a main unit, the data information to be written is preceded by conditioning information (INP 1, INP 2, etc). This actuates a loading means (UPK) for establishing a connection to an addressed module (LIM 1-LIM 32) with the aid of initial information written into an unchangeable memory (MIN) in the module.

Abstract: According to this invention, a field of useful data is split into a number of basic entities, called "data groups". Each data group is, in turn, split into smaller basic entities or "data blocks". Each resulting data block is inserted in a data packet to be transmitted through a teletext or videotext network. Therefore, an input coupler has two functional parts: a data group generator and a data packet generator.

Abstract: This disclosure relates to the instant method and system for controlling the interconnecting of a plurality of local communications networks. A source station and a destination station may respectively be adapted to be coupled to at least one communications channel of a communications path, which path includes a plurality of channels, each channel being assignable to at least one of a plurality of local data networks. The respective stations are adapted to determine the home network of the other respective stations with which the respective stations may communicate. Broadly, a source station, which has a message to transmit to a destination station, determines the home network of the destination and couples a first source receiver and a source transmitter to the home network of the destination for transmitting a packet from the source to the destination. A first packet may be transmitted when the source station acquires access to an idle channel of the destination home network.

Abstract: The invention relates to a broad-band, time-division multiplex, token-passing, ring local area network, with which both circuit-switched and packet-switched traffic, namely data, text, picture and speech traffic can be supported. The invention has for its object to provide a method of transmitting digital information in a ring having a comparatively high transmission capacity with which rapid access to the common ring transmission means can be obtained, without however high requirements being imposed on the processing speed of the stations. According to the invention this is in principle achieved by means of a method which guarantees that per time-division multiplex frame only one time slot, which is known to the station, needs to be accessed.

Abstract: A signal in HDBn code is transmitted with an auxiliary binary signal having a lower bit-rate on a digital transmission line. The HDBn code signal comprises predetermined sequences each including n+1 elements, n-1 central elements being zeros and a last element being a bipolarity violation mark. In each sequence of the HDBn code signal transmitted during each of binary elements of the auxiliary signal having a predetermined binary state, a bipolar mark in the sequence is permutated with a zero element having a predetermined rank in the sequence to derive an encoded sequence. The HDBn code signal is an information signal in the transmission line and the auxiliary signal can be a signal for remotely locating the repeater in the line from a monitoring end equipment of a monitoring system or for indicating performance factors of the repeaters, such as error rates, to the monitoring equipment.

Abstract: A duplicated switching system including a number of communication units wherein each digital word transmitted by an originating communication unit is conveyed via both of the duplicate time-multiplexed switches in the system and a destination communication unit autonomously selects the digital words to be used for further communication based upon whether the word error check portions can be derived from the word information portions. Advantageously, the system continues to operate in the presence of system faults not simultaneously affecting digital words from both time-multiplexed switches without any erroneous words being used for further communication and without involving a system central control.

Abstract: Data communications connections between interactive terminals and host computers generally exhibit long holding times, while the data density of the transmissions is sparse. The circuit switch of a switching system is an inefficient and expensive medium for this type of communication. Thus, the subject switching system uses a packet switch connected in parallel with the circuit switch to handle bursty data traffic from interactive terminals. A routing bit is set in the data stream from each port circuit to indicate the nature of the transmission and this transmission is then routed to the packet switch if it is a bursty data transmissions while voice messages are routed to the circuit switch.

Abstract: In order to increase the speed at which a determination is made as to which of a number of competing stations will occupy a particular block, the blocks are divided into a plurality of time slots and the various stations transmit probe signals into the time slots. Each station transmits its probe signal with a particular probability, with the probabilities preferably differing between respective stations. The number of occupied blocks in each frame can be counted to determine a degree of congestion, and the probe signal probabilities can be adjusted in accordance with the degree of congestion. Also if the degree of congestion is low, stations can transmit their packet signals directly without first transmitting probe signals, and the probe signal procedure will be followed thereafter only if a packet collision occurs.

Abstract: A telecommunication system for utilizing a telecommunication exchange intended for transmitting digital information between a plurality of extensions for transmitting between data terminals data information having different rates. Word forming means (18, 19) at the extensions subdivide the data flow into words of given length, buffer means (24) store a plurality of words before sending these out over the line, which is done with the bit rate given by the transmission system for digital information, and frame forming means (30) form frame heading words which precede the frames and have a plurality of subsequent data words. The frame heading word includes a frame locking word for synchronization on the receive side and a frame length word for indicating the number of the subsequent data words.