Abstract: In communications control unit for sequentially scanning a plurality of line sets to which full-duplex lines are connected, for reading out line control word provided in correspondence to the line from a memory when a data transmission/reception request exists in the line set, and for executing the data transmitting and receiving operations with the relevant line set, one line control word including both of transmission control information and reception control information is read out in the time slot assigned to one full-duplex line, and the data transmitting and receiving operations are simultaneously executed.

Abstract: A method and apparatus are disclosed for preserving a minimum or maximum interpacket gap length in an independently clocked data network, typically one following the ANSI-FDDI standard. A smoother is placed downstream of each elastic buffer in the network. The smoother detects the occurrence in an arriving stream of bytes of short preambles, i.e., those having fewer than a threshold number of idle bytes, and inserts some number n.sub.a additional idle bytes into such preambles. Subsequently arriving bytes are delayed by n.sub.a byte clock periods by, in a preferred embodiment, storing them in a FIFO sequence of registers. In order to be available for lengthening other short preambles when they arrive, the smoother also detects the arrival of long preambles, i.e., those having more than the threshold number of idle bytes, and deletes a number n.sub.d idle bytes from such long preambles.

Abstract: In a switching network for switchingly and selectively deliver a particular one of a plurality of input channel signals to a specific one of a plurality of ouptut channel lines according to a channel selection signal, the input channel signals are sampled at input channel sample-and-hold circuits by input channel sampling signals to produce sampled signals which are arranged time-serially at a combining circuit to form a combined signal. The combined signal is sampled at output channel sample-and-hold circuits connected to the output channel lines, respectively. An extracting signal is synchronous with a particular one of the input channel sampling signals and is applied to a specific one of the output channel sample-and-hold circuits according to the channel selection signal. The specific sample-and-hold circuit samples the combined signal by the extracting signal and extracts a particular one of the sampled signals corresponding to the particular input channel signal.

Abstract: A switch configurable communication network among many users, comprising forwarding units which individually present a communication tree with their ports as terminal nodes and a cross-point switch for connecting one user to another, for connecting users to a forwarding unit and for connecting one forwarding unit to another, whereby the cross-point switch can configure two users in point-to-point communication and can form modular tree subnetworks among the users by using the forwarding units.

Abstract: A computer interconnect coupler has a set of junctors which are assigned to channel transmitters and channel receivers for the routing of messages from the channel receivers which are addressed to the channel transmitters. When a message is received by a channel receiver, the channel receiver stores the beginning portion of the message in a first-in-first-out buffer, and sends a route message request to central switch logic. If the destination transmitter or receiver is busy, the central logic places the message request on a destination queue and returns a signal to the requesting source transmitter to turn on a flow control signal which is transmitted back to the data processing device having originated the message. Any message addressed to this data processing device, however, is inserted into the flow control carrier with pauses both before and after the message, and provisions are also made to allow the data processing device to return an acknowledgment code responsive to the imcoming message.

Abstract: A recognition system for comparing energy distributions of incombing emitters with known frequency spectrums is shown. Frequency spectrum analysis of randomly generated signals produces references against which the incoming communication wave may be checked. the recognition system recognizes a plurality of subchannel modulation types. Since there are many different subchannel modulation types in use today, small tactical weapons systems must recognize a number of different signals. Once certain parameters describing each subchannel modulation type are provided to the recognition system, the spectrum analysis of the subchannel modulation types is stored for subsequent use. This system provides for recognizing various FSK signals, PSK signals and OOK signals, as well as being adaptable to tracking other signals which are defined in terms of certain parameters.

Abstract: A vehicle multiplex system includes a multiplex controller mounted in a fuse block of the vehicle. Both power buses and control buses radiate from the fuse block, and the control buses interconnect the controller with respective input and output units distributed about the vehicle. Preferably, the controller selects one of the control buses as an active bus at any given time and isolates the remaining control buses both from the active control bus and from the controller. In this way, system reliability is improved, and electromagnetic interference is reduced. By positioning the multiplex controller in the fuse block, wiring requirements for the multiplex system are simplified and the multiplex system is more readily integrated into the electrical system of the vehicle.

Abstract: In a local area communication system comprising token rings (11) with synchronous bandwidth managers SBM (15) for issuing priority tokens for quasi-synchronous frames at regular intervals, the rings are interconnected by a time division muliplex PBX unit (21) via their SMB units. Buffers are provided in each SBM for synchronous information blocks transferred from and to the ring, and the TDM control (31) can independently access these buffers for TDM switching of the individual bytes of said information blocks. Besides this PBX interconnection for synchronous information or voice, the rings are also interconnected by a backbone bus or ring for transfer of asynchronous data between rings. A special slot rearrangement procedure is provided to improve the filling of time slots in the quasi-synchronous frames that are no longer used after release of a connection, to allow for adapting the frame length (number of issued slots) to the number of existing connections.

Abstract: An optical fiber communications system with a plurality of bidirectional channels and a protection channel is disclosed. Each channel has a respective identity which is transmitted in the traffic of that channel and in the event of a protection switch is identified in the protection channel traffic. A protection switch is effected by detecting a channel failure at the receive end of a span, transmitting a protection request on the return channel back to the transmit end of the span, and using this request in a controller for the channel to effect a protection switch, using an individual selector for the channel, if a priority scheme allows. The controllers are enabled or disabled under software control following a protection switch in accordance with the prevailing priority scheme. The arrangement provides for rapid protection switching.

Abstract: A multiplexer includes first and second frequency dividers and first and second selectors. The first frequency divider receives a clock signal which determines a multiplexing time slot and outputs a first signal every M (M.gtoreq.2) time slots. The second frequency divider receives the first signal from said first frequency divider and outputs N (N.gtoreq.1) second signals having different phases. The first selector converts N insertion codes such as a frame synchronization code and a service code into one code signal train on the basis of the second signals. The second selector receives a digital data signal train having an alternate repetition of a digital data signal using (M-1) continuous time slots and a gap of one time slot and inserts the insertion codes of the code signal train on the basis of the first signal.

Abstract: In a system which includes of subsystems, and a transmission medium for coupling them, and in which a token is sent to the transmission medium, whereby the transmission medium is occupied; a transmission control method characterized, at least, in that each of the certain subsystems appends a code indicative of a function of certain data to the token and sends the resulting data to the medium, and that the subsystem receiving the data refers to the code indicative of the function of the data, thereby to independently judge whether or not the data is to be accepted into the own subsystem.

Abstract: An apparatus for providing passive bus communication in an ISDN without use of services of a central office includes a passive bus suitable for ISDN D-channel frame communication, the passive bus having an echo channel and having a plurality of terminal devices coupled to the passive bus. A receiving circuit is coupled to the passive bus for receiving D-channel frames containing a SAPI address transmitted from the terminal devices over the passive bus. A decoding circuit is coupled to the receiving circuit for decoding D-channel addresses transmitted from the terminal devices over the passive bus. The decoding circuit includes a circuit for determining if one of the D-channel frames from the terminal devices include a predetermined SAPI address. A switching circuit is coupled to and responsive to the decoding circuit, and implements a logical communication channel between two or more of the plurality of terminal devices when the D-channel frame includes the predetermined SAPI address.

Abstract: A high bit rate data link is disclosed. The high bit rate data link comprises a group of individual low bit rate data links. A memory stores the addresses of all the low bit rate data links in the group. The memory is indexed by packets including an identification number for the group. The addresses of the low bit rate links are successively written into packets containing the group identification number so that these packets are evenly distributed to the low bit rate links comprising the group.

Abstract: For subscriber termination circuits of a digital time multiplex telecommunications system comprised in a group, an injection circuit is provided, individual to a group. The injection circuit comprises a switch exhibiting a gradual change of state both in switching on and switching off for providing timing for meter pulses provided by a meter pulse generator. The meter pulses are applied to the individual subscriber termination lines in a multiplex manner by way of contacts as well as test relays already present.

Abstract: Method of adjusting the interstation delay in an information transmission system comprising a large number of relay stations arranged in cascade and utilizing in one transmission direction the TDMA method, and a system to which such a delay adjusting method is applied.This method of adjusting the interstation delay in an information transmission system utilizing the TDMA principle can be advantageously used when the system comprises a large number of relay stations in a cascade arrangement. An adjusting range is imposed on the delay to be allocated to the transmission of data in order to avoid information jumps which may provoke overlapping on reception of these data. The adjustment of the delay is effected by starting with the relay station nearest to the central station, then the following relay station etc., and ending with the adjustment of the terminal station involved.

Abstract: A time slot interchange matrix is comprised of a plurality of matrix modules (50-56) each for receiving data on a plurality of channels and transmitting data on the same number of channels. Each of the modules consists of separate banks of random access memory that are interfaced with an intramatrix bus (70) for receiving data from each of the matrix modules in the system for storage therein during a collection frame. During a transmission frame, this information is randomly accessed in accordance with an interconnect pattern stored in a control RAM (122) for output from the digital matrix module. Each digital matrix module stores all of the information in the system such that the system is non-blocking for any given channel stored such that information is not impeded by the interconnect pattern of another digital matrix module. A digital bridge (80) is provided for collecting the information during a collection frame and then accumulating the information in a bridge IC circuit (137) as a conference.

Abstract: An NpR variable bandwidth control system comprises a class of systems specifically designed to control the access to a T1 link by traffic types that require different fractions of the transmission facilities simultaneoulsy. These systems can be incorporated into the software that is used to control DSC based T1 networks for special services. Essentially, wideband messages such as video signals are transmitted one at a time, whereas low bit rate data signals such as voice are transmitted in parallel. Such a form of transmission makes economical sense in the transmitting of such signals. A proportion p is applied to one of the group so that all data is equitably handled.

Abstract: A system for transmitting and receiving digitalized audio signals, particularly via satellites, wherein data sequences are arranged in timely succession within frames, wherein before transmission, the digitalized audio signal is converted to a digital signal representing the momentary frequency spectrum and, during subsequent coding of the digital audio signal to be transmitted, portions of this transformed signal are given different weights on the basis of psychoacoustic laws with respect to the accuracy of their representation.

Abstract: A switching system including a number of switching modules each having a plurality of access ports. Incoming and outgoing packet channels are extended between each switching module and an inter-module packet switch. Each of the switching modules includes both a packet switching unit and a circuit switching unit for switching information to and from the access ports. Each switching module further includes a control unit that controls the switching units and that generates inter-module control packets, and a communication interface that transmits inter-module control packets generated by the control unit on the incoming packet channel to the inter-module packet switch. The communication interface also transmits inter-module control packets received on the outgoing packet channel from the inter-module packet switch to the control unit.

Abstract: A packet communications network and apparatus for communicating information in voice and data packets transmits and receives voice and data in accordance with standardized frames of a standardized communications format such as a standard DS-1 type trunk. An apparatus is coupled to multiplex standardized channels into a single channel wherein voice or data signals are packetized into independently addressable packets synchronized on, for example, the DS-1 frame. The network includes voice and packet data concentration apparatus operable in a multiple node trunk environment to concentrate signals into independently addressable synchronously switchable packets, thereby to provide an efficient (high data capacity) interface between trunk terminations. Up to four times as much information can be transferred between nodes with the ability to switch between nodes as compared to conventional TDM and PCM communication without compression without the ability to switch between nodes.