Abstract: A QDPSK communication receiver includes a frequency source, apparatus for translating a received QDPSK signal having inphase I and quadrature phase Q components to baseband and a baseband demodulator. For each symbol period of the baseband QDPSK signal, a signal (I.sub.diff) representative of the inphase component of the phase different between immediately successive received symbols and signal (Q.sub.diff) representative of quadrature phase component of the phase difference between immediately successive received symbols is formed. In order to synchronize the frequency of the receiver frequency source to carried frequency of the received QDPSK signal, a preamble interval is defined during which a sequence of identified symbols is received.

Abstract: A distortion compensation circuit for power amplifier producing a prescribed distortion component receives an input signal having at least one carrier therein in a prescribed frequency range. The input signal is applied to a first circuit path having an amplifier that produces an amplified signal with the prescribed distortion component and to a second circuit path that delays the input signal without distortion. The output signals of the first and second circuit paths are combined in a first combiner to form a signal representative of the prescribed distortion component. A second combiner forms a signal having an amplified input signal component and inverted phase prescribed distortion component responsive to the output of the first combiner and the output the first circuit path.

Abstract: An appartus (10) attaching successive pairs of wires (12) to successive pairs of opposed contacts (15) of a connector (16) comprises a connector-carrying carriage (44,46) mounted for movement along a longitudinal axis. Each of a pair of ram assemblies (100) is mounted on opposite sides of the carriage for movement to and from a separate one of a pair of opposed contacts on the connector. Each pair of wire guides (58) is situated adjacent to a separate one of the ram assemblies for guiding a wire pulled thereacross into alignment with one of a pair the opposed connector contacts. Once each wire is aligned with the connector contact, each ram assembly is actuated to attach the wire to the contact. After wire attachment, an advancing mechanism (120, 126, 134, 142, 146) advances the carriage so that each of a successive pair of contacts is opposite a separate one of the ram assemblies.

Abstract: A probe for providing noise measurements of an electrical circuit includes at least one loop of wire connected to a plurality of conductors. The loop interconnects one or more signal-carrying ones of the conductors to one or more of the conductors carrying ground and has a portion which is substantially straight or is deformable to follow the path of a conductor in the electrical circuit. Preferably, the loop is formed so that this straight portion terminates in a right angle bend at each end. This loop serves as an inductive pickup which avoids the need for contact of the probe to the circuit under test and, thereby, provides more accurate noise measurements.

Abstract: A pitch detector system for use with speech analysis and synthesis methods having a plurality of identical detectors each responsive to a different portion of a speech signal for estimating a pitch value and a voter circuit responsive to the estimated pitch values for determining a final pitch value. The pitch detectors are identical in design which allows for an efficient software implementation since only one set of program instructions is necessary to implement all of the encoders. The voter subsystem may be implemented by a digital signal processor executing program instructions that calculate a pitch value from the estimated pitch values determined by the pitch detectors and a second set of program instructions for constraining the final pitch value outputted by the voter subsystem so that the calculated pitch value is in agreement with calculated pitch values for previous frames.

Abstract: To prevent an interruption of service due to a break in an optical fiber, the information being transmitted is normally sent along two diversely routed lightwave paths using two complete transmitter sections, one for each path. Briefly, in this invention a single optical transmitter which can be an optical modulator such as a lithium niolate switch is used to impress a digital signal on a CW optical beam to obtain two digital optical outputs. One output is normally used as the modulated line signal for one of two diversely routed paths. The other output, which is the complement of the modulated signal, is used as the modulated line signal for the other of the two diversely routed paths. When the complement of the signal is detected, complementation can be performed to retrieve the original bit pattern. The advantages over the prior art are significant. For example, only one tansmitter is required. The laser is on continuously and, therefore, there is no chirp.

Abstract: This invention is an optical memory device in which data is written, stored and read out in optical form without any conversion to electronics. The functions performed such as readout, reset and the like can be via electronic means, optical means, or a combination of both. The inherent bistability/hysteresis which is required for the memory function is obtained with a laser structure which includes a saturable absorber and, as a portion of the cavity, a waveguide.

Abstract: A network is disclosed for distributing a signal from a single source (18) to each of 2.sup.n (20.sub.1, 20.sub.2 . . . 20.sub.2n where n is an integer, such that the signals supplied to the loads each have substantially the same phase and amplitude. The network comprises 2.sup.n paths (22.sub.1, 22.sub.2 . . . 22.sub.2n), each coupling the source to a separate one of the loads. Each path is comprised of 2n+1 serially coupled segments 24.sub.1, 24.sub.4 . . . 24.sub.2n+1) with 2n-1 of the segments (24.sub.1, 24.sub.4 . . . 24.sub.2n-1) of each branch being common to another path. The segments in each path have corresponding impedances (Z.sub.1, Z.sub.2 . . . Z.sub.2n+1), respectively, which are selected so that each load is substantially matched to the source and that the internal reflection of the signals within each path is minimized.

Abstract: A mineral-oil-free composition of matter useful as a cable splice encapsulant comprises between about 20% and about 60% polyurethane, by weight of the cured encapsulant, the balance comprising plasticizer(s) and optionally, additives such as catalysts, antioxidants and fungicides.

Abstract: In order to provide a substrate such as an optical preform rod (24) which suitable for insertion into a tube and which has a transverse cross section that is substantially circular and disposed concentrically about a longitudinal axis of the substrate substantially along its entire length, a force-applying means such as a graphite roller (52) is adapted to be moved incrementally toward an axis of rotation (35) about which the preform rod is turned rotatably. Movement is discontinued when there is an indication that the force-applying means has been in continuous engagement with the preform rod for at least a predetermined portion of the periphery of the rod. In a preferred embodiment, the engagement of the force-applying means and the preform rod is discontinued after a predetermined time whereafter the force-applying means again is moved toward the axis of rotation.

Abstract: A textured planar surface (15) on a semiconductor chip (10) is distinguished from a volume of surrounding bonding material (12) by first illuminating the chip and the bonding material with light directed normal to the surface. Thereafter, the image of the surface (15) is captured by a television camera (30) such that the textured planar surface is in focus and the bonding material appears out of focus to the camera. The image captured by the camera is processed by a vision processor (32) which first determines the intensity gradient for each separate small area (pixel) in the image and then creates a gradient image based on the pixel intensity gradients. The gradient image is binarized by causing each pixel to appear dark or bright, depending on whether its intensity gradient is below or above a threshold value.

Abstract: A forced encapsulation system and method that can be advantageously used to encapsulate cable splices e.g., multiconductor communications cables. Containment means are formed around a substrate comprising part of at least one cable, and secured to the cable, thereby forming an enclosure into which liquid encapsulant can be introduced under pressure and in which the encapsulant can be maintained at pressure above ambient pressure. In a preferred embodiment, the containment means comprise a containment bag formed in situ from an elastomer sheet and sealed to the cable sheaths, with a reinforcing outer enclosure surrounding the containment bag.

Abstract: This adjunct processor arrangement performs a centralized call screening function to provide computer port access security. Every call origination in the telephone switching system from a calling party to a protected computer port is interdicted by the telephone switching system and routed to the adjunct processor. The calling party receives a series of prompts from the adjunct processor to provide identification information, such as login, password, and voiceprint information. The adjunct processor validates the identity of the calling party using this identification indicia and initiates a callback operation. The adjunct processor disconnects the calling party from the connection, calls the calling party back and then uses the data call transfer capability of the telephone switching system to connect the calling party to the computer.

Abstract: Apparatus comprising a bakeable high vacuum system using cryopumps is disclosed. Auxiliary cooling means in thermal contact with the primary pumping stage of the cryopump remove heat from the cryopump, whereby the walls of the cryopump may be heated during operation of the cryopump, such that the cryopump can be baked. This can result in substantially improved attainable pressure in the system.

Abstract: The operation of neural networks begins with the initialization of the system with the information to be processed. Presently, this initialization is performed by pinning the system with rather large analog or digital signals representing this information. The problems associated with the high power required for such initialization are eliminated and accuracy is maintained by utilizing a specific set of input points and appropriately positioned switches. In particular, a switch corresponding to each amplifier is introduced, and the initializing data is introduced between the amplifier and this switch.

Abstract: An animal-resistant optical fiber cable (20) includes a core (22) which comprises a transmission medium and a sheath system. The sheath system includes an outer jacket (65) and a dielectric armor (40) in the form of a shell. The shell comprises a plurality of longitudinally extending preformed segments (42--42) each having an arcuately shaped cross section transverse to a longitudinal axis of the cable and each comprising glass fibers embedded in a matrix material. Each of the segments covers less than half of the periphery of the core and, in a preferred embodiment, eight segments are used. Further, the shell segments are stranded helically about the core with longitudinal edge surfaces of adjacent segments being in engagement with each other. The shell segments not only provide rodent protection for the cable, but also they provide suitable tensile and compressive strength. Further, because the cable has an all-dielectric sheath system, it is inherently lightning, corrosion and EMP resistant.

Abstract: A redundant (multiple) bus system for interconnecting a plurality of data source and destination entities and arranged to direct data communications over an alternative bus in the event that a prior call to a destination over a first bus was unsuccessful. Each source entity maintains a table designating a separate logical path over each bus to each destination entity, marking each path designation in accordance with the success or failure of calls directed through the path. The bus selection for delivering a communication to any destination is determined in accordance with designation markings for the paths to the destination and independent of designation markings for paths to other destinations whereby a bus may be selected for a delivery to one destination even though prior deliveries over the bus to other destinations have failed.

Abstract: Apparatus for loading components into a component insertion machine. The aratus comprises structure releasably mounted on component magazine loading apparatus to retain components in component magazines received by and aligned in the component magazine loading apparatus. The structure is removable after installation of the component loading apparatus on the component insertion machine to enable components to be selected by the component insertion machine from the component magazines.

Abstract: A cable (20) which is particularly suited to the transmission of substantially error-free data at relatively high rates over relatively long distances includes at least two pairs of individually insulated conductors (42--42). The pairs of individually insulated conductors are enclosed in a tubular member (51) comprising a plastic material. A metallic shield (54) may or may not enclose the tubular member, and in a preferred embodiment, a plastic jacket (58) is provided. The twist length of each pair of insulated conductors does not exceed a value equal to the product of about forty and the outer diameter of the plastic insulation. Further, the twist lengths among the conductor pairs are varied in accordance with a twist frequency scheme modulated by non-uniform increments of twist frequency.