Abstract: An speech analysis and synthesis system where pitch information for excitation is transmitted during voiced segments of speech and modified residual information for excitation is transmitted during unvoiced speech segments along with linear predictive coded (LPC) parameters. The speech analysis portion of the system uses a pitch detection circuit to determine when the speech is voiced or unvoiced and to calculate the pitch information during voiced segments. A multi-pulse excitation forming circuit generates the modified residual signal which is obtained from the cross correlation of the residual signal and the LPC-recreated original signal. The pitch detection circuit controls a multiplexer which selects either the output of the multi-pulse excitation forming circuit or the output of the pitch detection circuit for transmission as the excitation information with LPC parameters to the synthesizer portion of the system.

Abstract: In an optical switching network, a master optical space switch is interconnected with remote slave equipment for switching block-multiplexed messages among the remote equipment. The master optical space switch responds to a frequency reference clock and steps through a sequence of states, or configurations, for establishing various routes among the remote equipment for appropriately routing the messages to correct destinations. The frequency reference clock also is distributed to the remote equipment. During one of the states per frame, each remote slave equipment transmits a distinct signature signal. All of the slave equipments are connected through the master optical space switch to return to themselves their own signals transmitted during that time slot. Each remote slave equipment compares the returned signal with the originally transmitted signature signal to determine how much the round trip delay has varied from a nominal value.

Abstract: A preform for fabrication of a glass fiber optical transmission line is prepared by chemical reaction of vapor ingredients within a glass tube. Reaction, which may be between chlorides or hydrides of, for example, silicon and germanium with oxygen, occurs preferentially within a constantly traversing hot zone. Flow rates and temperature are sufficient to result in glass formation in the form of particulate matter on the inner surface of the tube. The particulate matter deposits on the tube and is fused with each passage of the hot zone. Continuous rotation of the tube during processing permits attainment of higher temperatures within the heated zone without distortion of the tube.

Abstract: Cordage (17) which may be used for any of the commonly marketed lengths of etractile cords comprises an array of a plurality of conductors (11--11) each insulated with a suitable plastic material. The array of conductors is enclosed in inner and outer jackets (52, 54). The inner jacket comprises a polyvinyl chloride (PVC) plastic material, for example, and has a thickness of about 0.015 inch. Covering the inner jacket is an outer jacket comprising a polyvinyl chloride plastic material having a thickness of about 0.005 inch and having a colorant constituent. The PVC composition of the inner jacket is such that it is a less expensive composition than that of the outer jacket. Enclosing the outer jacket is a layer (56) which comprises a top coating material. The top coating material provides the cordage with enhanced retractibility and prevents discoloration as well as plasticizer migration from the outer jacket.

Abstract: Efficient high frequency operation of magnetic devices is achieved by utilizing ferrites that have a low power dissipation hysteresis characteristic and by designing these magnetic devices to operate within an operational range where all applied magnetic forces to the magnetic core have a substantially linear constant permeability response. Within this operational range the hysteresis loop of the selected ferrite material approximates an ellipse with very little area encompassed between the increasing and decreasing B-H locus of the hysteresis loop. The cyclic energy dissipation is significantly reduced as compared to conventional magnetic operations and high frequency operation can be achieved with very high efficiencies.

Abstract: In a hybrid integrated circuit encapsulation process, each lead array (14) is encompassed by an elongated C-shaped barrier member (17) which clamps onto the portions of the lead array adjacent the substrate (11); that is, opposite sides of a slot (18) in the barrier member grasp opposite sides of the leads. Thereafter, the uncured RTV silicone (15) is dispensed onto the substrate, flows over and encompasses chips (12) mounted on the surface of the substrate and is prevented from flowing along the leads (14) by the C-shaped members (17), each of which, due to its configuration, constitutes a barrier to fluid flow, either along the length of the various leads or over the top of the C-shaped member. In one embodiment, levers (19) may be integrated onto the C-shaped member opposite the substrate to aid in prying open the slot to permit the leads to be easily inserted into the C-shaped member.

Abstract: A communications cable comprising a core of transmission media such as optical fibers, for example, disposed in a core tube and a sheath system (32) includes provisions for preventing the movement of water within the cable core. Water blocking provisions (26) are disposed in the core tube and may comprise a tape or a yarn, for example, or both. The tape may comprise substrate tapes between which is disposed a superabsorbent material in powder form which upon contact with water swells and inhibits the further movement of the water. In another embodiment, a water swellable yarn may extend longitudinally linearly with the optical fibers in the core.

Abstract: To overcome the deleterious effects of the nonuniform frequency modulation response in semiconductor lasers due to current injection in direct frequency modulation applications, it has been determined that the linewidth enhancement factor .alpha. be made as large as possible. In one embodiment, distributed feedback lasers well suited for frequency modulation lightwave communication systems are designed to have an integrated feedback element such as a corrugation grating whose effective pitch is selected to cause the Bragg wavelength and, therefore, the laser operating wavelength to be longer than the wavelength at substantially the maximum gain or gain peak in the semiconductor structure without the grating. That is, the wavelength of the grating is effectively detuned toward the longer wavelength and lower energy side of the peak of the gain profile.

Abstract: A call appearance reservation arrangement where any number of the call appearances of a directory number are reservable, and where a reservation type is defined for the directory number such that calls to and from the reserved call appearances are processed in accordance with one of a number of possible reservation types, such types for example including: (1) origination only, (2) termination only, and (3) origination and priority termination only.

Abstract: A plurality of digital signals of one or more digital transmission bit rates are arranged to be combined by employing a unique common channel frame format. The channel frame format includes a plurality of data bit positions and a plurality of overhead bit positions. The number of data bit positions used is dependent on the particular incoming signal. Similarly, the number of frames generated during a specific common framing interval is dependent on the digital transmission bit rate of the particular signal. Specifically, the number of channel frames generated during the common channel frame interval is dependent on a number of equivalent so-called lowest transmission bit rate signals included in the particular signal being formatted. The overhead bits are distributed in the channel frame format.

Abstract: A key telephone management controller system enabling telephone customers to control and implement changes to customer key telephone systems served by a telephone switching system. Apparatus and a method interactive with telephone customers records customer-selected key telephone button and line features and controls the telephone switching system to assign the customer-selected button and line features to telephone sets of the customer key telephone system.

Abstract: A grating coupler is combined with a quantum well index modulator and an optical waveguide to alter the reverse or forward coupling characteristics between two different propagation modes of the system.

Abstract: An apparatus for attaching each of a successive pair of wires (12) to each of a pair of contacts (13), seated in opposed recesses (14) in a connector (16), comprises a base (18) on which a connector-carrying carriage (26) is slidably mounted for movement along an axis (24). Each of a pair of ram assemblies (32) is mounted on opposite sides of the path of travel of the carriage (26). Adjacent to each ram assembly (32) is a wire guide (58) which has an upwardly inclined pin (74) which provides a path for pulling a wire into alignment with a separate one of the ram assemblies (32). Once aligned with the ram assemblies, the wires 12 are then rammed by the ram assemblies against the corresponding contacts (13).

Abstract: A dual wavelength optical coupler is disclosed which provides either bidirectional or unidirectional communication at different wavelengths over a single fiber. The coupler utilizes a dichroic filter and a set of three lenses to achieve dual wavelength communication. Additional blocking filters may be incorporated to decrease the degree of optical crosstalk present in the system.

Abstract: Optoelectronic chips, such as Group III-V compound lasers and photodiodes, are mounted on a single-crystal silicon base, and are optically interconnected to one another by silica waveguides and couplers integrally formed on the base. Integrated circuit chips to provide electronic function are also mounted on the base. Various schemes for optically coupling and aligning lasers, photodiodes and optical fibers to the waveguides are described. Also described is the use of a single-crystal silicon lid, which serves to provide optical and electrical isolation between chips on the base, as well as a plug-in arrangement in which the edges of the base are adapted to receive parallel guide rods.

Abstract: Combinatorial (Boolean ) logical functions are provided in a programmable optical logic device by combining a symmetric self-electrooptic effect device (S-SEED) with a logic control element for optically programming the S-SEED to initiate logic operations in a predetermined mode. A predetermined reference threshold optical signal is applied to one input of the S-SEED while first and second optical data signals are jointly applied to another input of the S-SEED to permit the desired combinatorial logic operation to be performed on the optical data signals by the optical logic device. As such, the programmable optical logic device is said to perform threshold logic operations. Logic operations which may be programmed into the optical logic device include AND, OR and NOT functions. A single optical signal is provided as output from each optical logic device.

Abstract: A packet switch arrangement in which a first plurality of user devices is connected to a packet network by a first interface unit and a second plurality of user devices is connected to the packet network by a second interface unit. A virtual circuit is established between the interface units and control information is exchanged over the virtual circuit. The control information defines virtual channels on the virtual circuit and ones of the first and second pluralities of user devices which are to be sources and destinations for data in the defined virtual channels. Data from user devices is packetized and transmitted in the virtual channels by the interface units in accordance with the exchanged control information. Further, packets received in virtual channels on the virtual circuit are distributed to user devices by the interface units in accordance with exchanged control information.

Abstract: A sensory type pattern such as a speech or other sound pattern is analyzed to obtain the spectral distribution of the neural response thereto. A plurality of logarithmically related neural response intensity threshold signals is formed. The frequency spectrum of the sensory type pattern is divided into a plurality of overlapping spectral portions and the waveform of each prescribed spectral portion is partitioned into successive time segments. For the current time segment of each spectral portion waveform, the time intervals between crossings of the neural response intensity threshold level signals by the spectral portion waveform are detected and signals representative of the counts of inverse time intervals between the crossings of the plurality of levels are generated to form an inverse time interval histogram for the spectral portion.