Abstract: A circuit arrangement is provided for a communications system for transmitting serial bit message information, particularly for multiplex data transmitted within optical transmission systems, by way of which local networks having loop configurations and equipped with corresponding switching devices, a plurality of terminal equipment processing different types of communication being connectible to the local network in an arbitrary combination with one another, the plurality being adapted to the different types of communication with respect to quantity of data transmission and data transmission rate within a frame, and in view of the method of transmission.

Abstract: A bidirectional digital transmission system with echo-cancellation allows the measurement of the received data signal and the automatic adaptation of the attenuator and of the line equalizer. They are implemented by using circuits already present in a conventional system, in addition to auxiliary circuits.

Abstract: A binary image is reduced in size by a method including the steps of: storing the image in bit sequence; dividing the image into transposable blocks; transposing by look up table, for each block having any nonzero data, each group of 6 bits along a first axis to a group of 5 bits; transposing by look up table, for each block having any nonzero data, each group of 6 bits along a second axis to a group of 5 bits; storing said transposed blocks.

Abstract: An optical repeater for an optical digital transmission line has a pair of in-service monitoring circuits (55, 55') each of which includes a flip-flop (57) for dividing frequency of transmission data to derive commands and burst carrier in the first line (54). A counting means (59, 61) is provided for detecting parity errors and counting the errors in an opposite second line (65). A timing generation means (62) is provided for reading out the counting means (61) upon receipt of the burst carrier. A phase modulator (64) provides phase modulation to a clock pulse in an opposite second line (65) according to the output of the timing generation means (62). The number of errors in the second line (65) is stored in the counting means (61) according to commands in a first line (54) from a terminal transmitter (52). The content of the counting means (61) is forwarded to a terminal receiver (66) through phase modulation of clock pulses in a second line (65) upon receipt of the burst carrier.

Abstract: A remote control unit integrator console includes a console tray to hold a plurality of infrared remote control transmitter units of various sizes and shapes. The tray includes a front hood which houses a mechanism for transferring infrared signals from the control units toward the appliances to be controlled. In one embodiment the infrared transfer mechanism includes a set of reflectors capable of efficiently reflecting infrared energy. In another embodiment, the infrared transfer mechanism includes infrared photo detectors connected to amplifiers which drive either a set of infrared emitters positioned in a diverging array or a single infrared emitter mounted in such a manner as to be pivotable. In still another embodiment, the coded infrared signals from the infrared remote control units are converted to radio signals which are received and reconverted to coded infrared signals by receiver units close to the controlled appliances for control of the respective appliances.

Abstract: An order wire system which can be used during installation and maintenance of an optical fiber communication system comprises an optical fiber order wire to which engineers can connect at remote sites communication sets each of which includes a microphone and earphone allowing the engineers to communicate with each other. Full duplex and multi-party operation can be achieved with the sets according to the invention and, because the signals are regenerated, the range of operation is considerable. Both analog and digital communication is contemplated and different specific circuits are proposed. In a typical analog configuration, the microphone output is fed to first and second frequency modulators operating respectively at first f.sub.1 and second f.sub.2 center frequencies. The outputs of the modulators are summed and passed to a laser driver and laser which is optically coupled both to the upstream and the downstream side of the order wire.

Abstract: In an optical communication system, transmitter/receivers located remote from each other have an identical construction and are accurately positioned relative to each other by means of photodetectors. Each apparatus includes a transmitter section and a receiver section which are disposed in a common transparent housing. Such a construction is applicable even to a repeater between the remote apparatuses by building another set of transmitter and receiver sections in the apparatus.

Abstract: A system for compressing digital data maintains a code table of plaintext symbols at a transmitting location. Blocks of plaintext symbols in a message are encoded using the code table which table is updated using an update algorithm. The codes for those blocks are transmitted to a receiving location where a second code table is maintained. At the receiving location, the transmitted symbols are decoded using that second code table. That code table is also updated by applying to the plaintext symbols recovered during the decoding process the same update algorithm used at the transmitting location so that the two code tables are the same at any given point in the transmission.

Abstract: Logic devices for frequency encoded trinary logic signals are simulated by standard binary circuits. The binary circuits include frequency sensing and frequency selecting devices at the inputs and outputs thereof for decoding the frequency encoded trinary logic signals to binary level logic signals and for frequency encoding the resulting binary output to trinary logic signals. Optical encoding using the three primary light frequencies provides a convenient trinary signal format for the frequency encoded signals. A latch register, a shift register, a half adder and full series and parallel adder circuits are disclosed.

Abstract: A multi/demultiplexer is disclosed wherein the light-conducting fibers are cemented into a perforated plate made of a photolithographically etchable material, and their terminal faces are ground down and polished together with the surface of the perforated plate. To compensate for focusing differences, a plate of appropriately matched thickness is disposed between the transparent supporting block and the surface of the perforated plate.

Abstract: A monolithically integrated circuit is described for multiplexing parallel electrical data into a serial bit stream for transmission by fiber optics to a remote utilization apparatus and for demultiplexing a serial bit stream received from a fiber optics transmission path from a remote source. The integrated circuit uses a separate fiber for transmission and for reception, and in the transmission mode, encodes the data, which is clocked by on chip clocking into a self-clocking three-level code. The integrated circuit utilizes GaAs as the substrate material and is capable of transmitting data at bit rates in excess of 1/2 gHz.

Abstract: The present invention relates to a lightwave communication system, and associated transmitters (13) and receivers (14), which uses both spread spectrum, code-division-multiple-access (SS-CDMA), and wavelength-division-multiplexing (WDM) techniques for 2-way transmissions over a lightwave waveguide arrangement (11) to use the overall spectrum of the waveguide arrangement (11) while providing sufficient interference rejection of randomly spaced carriers, and associated signals, which may drift into the bandwidth of transmissions of other transmitter/receiver pairs due to instabilities in carrier laser sources (20). Techniques are also disclosed for a transceiver (10.sub.i) acquiring a 2-way link with another transceiver (10.sub.j), while other transmitter/receiver pairs are concurrently communicating using WDM, SS-CDMA, signal transmissions.

Abstract: A bit compression multiplexer for a pair of time division multiplexed digital bit streams each one of which includes a plurality of PCM encoded signals deposited in separate and distinct channels and signaling bits multiplexed therewith. The encoded signals are bit compressed (22), and then multiplexed and grouped (25) into clusters. Each of the multiplexed compressed signals occupies a separate and distinct channel of a repetitive frame that includes a plurality of clusters and a corresponding number of additional channels, called delta channels, each one of which is associated with a given cluster and is proximate thereto. The signaling bits are extracted (21) from the pair of digital bit streams, reformatted (24) and then placed in predetermined bit positions of the delta channels. The signaling bits in a given delta channel are associated with the compressed signals of a cluster proximate thereto. The combination of a cluster and its related delta channel comprise a bundle.

Abstract: An optoelectronic switching matrix which can be configured to form a variety of signal processing elements, such as a digital switched filter, a digital word generator, a programmable bandpass filter, programmable delay, etc. Optical or electronic delay apparatus is connected between output and input ports of the matrix, and can be switched to provide delays or resonant loops. A versatile signal translation element is thus realized.

Abstract: There is disclosed an acousto-optic filtering apparatus which includes Bragg cells in the signal path and in the local oscillator reference path of the apparatus in order to permit relatively high frequency signals to be detected by a relatively low frequency detector mechanism.

Abstract: A fiber optic switching system and method is described which is capable of rapidly switching among a number of closely spaced optical rods for optical connection with a communications channel, while alleviating alignment problems caused by vibration and similar environmental conditions. Focusing lenses are moved relative to stationary multirod cables, and brought into coarse alignment with desired rods in each cable in a programmed switching sequence. At each coarse lens position a fine alignment is achieved between the lens and rod by directing an optical alignment beam along the focal axis of the lens, reflecting the beam off the rod, and sensing the portion of the alignment beam which is reflected back through the lens as an indication of the misalignment. The misalignment detectors form part of a servomechanism that rapidly adjusts the lens position in response to detected misalignments to bring the lens into alignment with the desired rod.

Abstract: An automatic inspection system detects foreign materials included in a sheet of transparent or translucent resin material such as a polyethylene compound. The automatic inspection system comprises an extruder for extruding a resin material into a sheet, means for withdrawing the extruded sheet along a path of travel, means disposed between the extruder and the withdrawing means for permitting the sheet to having down by gravity into a U-shape, sensor means for detecting a vertical position of the U-shaped portion of the sheet, controller means for adjusting the speed of sheet withdrawal for the withdrawing means in response to the output signal from the sensor means, a source of light disposed on one side of the path of travel of the sheet, an image sensor camera disposed on the other side of the path of travel of the sheet in confronting relation to the source of light for receiving light emitted from the source of light and having passed through the sheet to detect foreign materials included in the sheet.

Abstract: A communication apparatus for controllably bidirectionally transferring information between a vehicle and a docking station advantageously utilizes pulsed radiant energy for effecting the information transfer. A first radiant energy emitting device and a first radiant energy detecting device is located on the vehicle and a second radiant energy emitting device and a second radiant energy detecting device is located on the docking station. A first frequency control device recieves electrical signals from the first radiant energy detecting device, produces pulse control signals having a nominal frequency which is variable within a predetermined frequency range, and controllably delivers the produced pulse control signals at the nominal frequency to the first radiant energy emitting device located on the vehicle.

Abstract: A system for sampling data, converting the same to light, and transmitting the light to a remote receiver via an optical fiber. A demultiplexer is provided at the remote end of the optical fiber.

Abstract: A cross-talk suppression circuit is disclosed for use in an optical communications system which employs a light-emitting diode. A video signal and an audio-modulated carrier signal are both coupled to the light-emitting diode. A cross-talk reducing circuit is provided to couple the audio-modulated carrier signal to the light-emitting diode. The circuit comprises a voltage-controlled phase shifter for coupling the audio-modulated carrier signal to the light emitting diode, the phase shifter having a phase shift that is controlled by the video signal.