Abstract: Known dispersion-compensating (DC) optical fibers typically are sensitive to small changes in fiber parameter (e.g., fiber diameter and/or core refractive index), and thus are difficult to manufacture. The disclosed DC fibers are relatively insensitive to small departures from the nominal fiber parameters, and are therefore more manufacturable. Exemplarily, the nominal refractive index profile of a DC fiber is selected such that the fiber supports LP.sub.01 and LP.sub.02 (and typically one or more further higher order modes), and the dispersion is substantially all in LP.sub.02. The total dispersion is more negative than -200 ps/nm.km over a relatively wide wavelength range. The nominal refractive index profile typically comprises a refractive index "ring" that is spaced from the fiber core.

Abstract: A method of forming electromigration resistant integrated circuit runners is disclosed. A collimated beam of particles is directed toward a substrate to form a metal nucleating layer. Then a non-collimated beam is used to form the rest of the metal layer. Then the layers are patterned to form runners.

Abstract: A self-verifying identification card having an image area which may contain a portrait, a finger print, a retinal image, or all of these together with an image signature which is derived from scanned intensity measurements taken from the image area. In the verification process, the image is scanned and aligned with respect to reference points corresponding to the original printing process which created the card, and intensity values, their averages, or any other function are compared to information provided by the image signature. Mathematical transformations, such as a one-way hash, an encryption, a compression algorithm, or a truth table may be used to encode the image signature. Alignment markers aid in scanning the image and the image signature. The use of average values aids in reducing noise and the use of comparison functions makes the process less sensitive to variations among scanners.

Abstract: A method and apparatus for reducing noise in optical communication systems, wherein the frequency of light output from a signal laser is modulated or dithered to broaden the optical spectrum of the signal laser. The broadening allows error-free data transmission within signal bands, despite the presence of optical beat interference. Different dithering tones are emitted by each laser in the network. The dithering tone for each signal laser in an optical network is chosen so that distortion resulting from the dithering tone falls outside the signal bands.

Abstract: A method and device are disclosed that utilize a spread spectrum coding process for processing a signal having first and second time portions to achieve unequal error protection of the time portions by variably modulating the power of one segment relative to the second segment. In such a signal, the first segment contains information that is more significant, i.e., more sensitive to error, than the second segment and the power modulator increases the average power of the signal during the first time portion relative to the average power of the signal during the second time portion. Preferably, the power increase of the first time portion is proportional to the power decrease of the second time portion so as to maintain overall system power requirements. The method and device are particularly suited for a digital cellular telephone systems such as DS-CDMA. In such a system, the signal is spread by a single spreading sequence.

Abstract: A method for improving the linearity of a signal coupling device having a ferrite core transformer comprises the step of demagnetizing the ferrite core. The resulting signal coupler has substantially zero remanent magnetism.

Abstract: A mold assembly includes first and second housings having generally curved surfaces inside the mold cavity. The first housing has apertures extending therethrough. The second housing may have apertures, axially aligned with the apertures of the first housing, extending partially or completely therethrough. At least one guided, flexible, elongated rod member is configured for reception in the apertures of the first and second housings, the rod members being movable in a direction non-parallel to a direction of movement of the mold assembly with respect to the rod members. The mold-assembly is particularly useful for forming a molded body having a plurality of apertures, aligned in arbitrary non-parallel directions relative to one another, extending therethrough.

Abstract: Apparatus and methods for generating a set of defective images from a model image. Defect parameters used with the apparatus and methods specify classes of defects including resolution, blur, threshold, speckle, jitter, skew, distortion of width and height, offset from a baseline, and kerning. The parameters further permit specification of a range of sizes of the defects and a distribution of the defects within the range. Within the apparatus, actual values for the defects are generated randomly within the specified ranges and distributions. The model image may be represented by means of pixels or by a format which describes the model image's shape. The user may specify the number and the size of the defective images. The defective images are useful for inferring accurate and efficient image classifiers for use in image recognition devices such as optical character readers.

Abstract: Electrical connections with terminals on a protector module mounting panel are protectively shielded from the effects of moisture condensation and other deleterious environmental conditions. The panel is placed in a housing having a top opening and a bottom opening, and wire leads are connected to the terminals. A pan member is placed across the bottom opening of the housing, to define a clearance gap between the pan member and the housing. The wire leads are routed through the clearance gap, and the connection terminals are protectively shielded by a sealant material which may be poured into the pan member from outside the panel housing through the defined clearance gap, and allowed to harden.

Abstract: A key-phrase detection and verification method that can be advantageously used to realize understanding of flexible (i.e., unconstrained) speech. A "multiple pass" procedure is applied to a spoken utterance comprising a sequence of words (i.e., a "sentence"). First, a plurality of key-phrases are detected (i.e., recognized) based on a set of phrase sub-grammars which may, for example, be specific to the state of the dialogue. These key-phrases are then verified by assigning confidence measures thereto and comparing these confidence measures to a threshold, resulting in a set of verified key-phrase candidates. Next, the verified key-phrase candidates are connected into sentence hypotheses based upon the confidence measures and predetermined (e.g., task-specific) semantic information. And, finally, one or more of these sentence hypotheses are verified to produce a verified sentence hypothesis and, from that, a resultant understanding of the spoken utterance.

Abstract: An improved fiber optic cable connector is provided that exhibits a consistent return loss rating of 60 dB or better. The connector comprises matable connector housings that terminate the ends of respective optical cables to be joined. Within each housing, the optical fiber of the respective cable is secured within a ceramic ferrule that extends axially of the connector. The endface of each optical fiber is exposed at the end of its respective ferrule. The ends of the ferrules are ground and polished in such a way that the endfaces of the optical fibers exhibit a planar undercut with respect to the lip of the axial passageway in which the fibers are secured. When the ferrules are brought and pressed together end-to-end as the connectors are mated, the material of each ferrule compresses until the endfaces of the optical fibers engage each other with near null pressure.

Abstract: In an optical transmitter, an input optical fiber delivers an optical signal to a fiber coupling modulator whose reflective surface is transformable in response to the data to be transmitted. In a first state of the modulator corresponding to a first data value, the reflective surface is flat and smooth. The optical signal, which may be a continuous-wave light, is reflected from the surface and efficiently coupled to an output fiber. In a second state of the modulator corresponding to a second data value, the reflective surface is controllably deformed to cause an aberration in reflecting the optical signal. As a result, a much reduced amount of light energy is coupled to the output fiber.

Abstract: An optical planar waveguide notch filter employs a waveguide with first, second and third regions. The first and third regions have structures for propagating an optical signal in a first transmission mode. The second region is located between the first and third regions and has a structure in which an optical signal propagates in the first transmission mode as well as at least one other higher order transmission mode. The structure of the second region further couples a particular wavelength band of the signal propagating in the first transmission mode to at least one of the other transmission modes. This coupling causes an attenuation of energy of such bandwidth in the signal propagating in the first transmission mode. As a result, the signal propagating from the second region to the third region in the first transmission mode is a notch filtered signal possessing an attenuation at the particular wavelength band.

Abstract: In accordance with the invention, a microwave vacuum tube device, such as a traveling wave tube, is provided with an electron source comprising activated ultrafine diamonds. Applicants have discovered that ultrafine diamonds (5-1,000 nm diameter), when activated by heat treatment in a hydrogen plasma, become excellent room-temperature electron emitters capable of producing electron emission current density of at least 10 mA/cm.sup.2 at low electric fields of 10 V/micrometer. Sources using these diamonds provide electrons for microwave vacuum tubes at low voltage, low operating temperature and with fast turn-on characteristics. A multiple grid structure is described for providing high quality electron beams particularly useful for traveling wave tubes.

Abstract: An interconnection system comprises a circuit board having signal conductors for carrying electrical signals. The circuit board includes a plurality of contact pads coupled to each one of said signal conductors. An elastomeric compression interconnect is releasably disposed next to the contact pads of the circuit board. The elastomeric compression interconnect includes a composite material having magnetic, electrically conductive substantially spherical particles disposed in a nonconductive matrix material adapted to align into mutually isolated conductive chains. A radio frequency flex circuit is also releasably disposed next to the elastomeric compression interconnect. The flex circuit is made of a dielectric material and a bonding material exhibiting substantially low signal loss.

Abstract: A method of connecting arrays of optical wavepaths is described employing externally located connector pads. After optically aligning the arrays to be connected, the connector pads are bonded to the arrays and then to each other. In the preferred embodiments, the pads, which typically are thin silicon wafers, and the arrays are metalized and then soldered together. The use of connector pads to connect arrays of optical transmission paths results in sturdy, stable connections. The technique is fast, simple and inexpensive, and is consistent with current alignment procedures. By using solder to secure the pads to the arrays and to each other, connections can be undone and then redone. Inasmuch as all connections are external to the optical paths, there is no deterioration of the optical connections with time.

Abstract: An optical transceiver assembly for use in a bidirectional system includes a beam splitter to direct an incoming signal to a photodiode. An outgoing signal from a laser diode is partially transmitted and partially reflected by the splitter. The reflected signal, which may reach the photodiode, constitutes crosstalk which is reduced by means of a cavity positioned to receive the reflected signal and an oblique surface within the cavity adapted to prevent much of the reflected signal from reaching the photodiode.

Abstract: A wireless cellular voice system and a wireless packet data system cover a common service area consisting of a plurality of cells, and share RF spectrum in providing their respective services to: AMPS phones, CDPD handheld data terminals, and combined AMPS-CDPD subscriber sets. Control of AMPS wireless communication and switching is vested in an AT&T 5ESS.TM. switch and an AT&T 3B20.TM. Access Manager. Control of CDPD communication is vested in a Sun SPARC Data Network Processor operating under standard CDPD protocol. A high speed bus of the Access Manager is extended to the SPARC processor to facilitate coordination of use of the shared wireless channels; and to allow the AMPS facility to originate data messages to combined AMPS-CDPD subscriber sets to implement AMPS data features, e.g., VOICE MESSAGE WAITING; ELECTRONIC MAIL NOTIFICATION; PAGING; and CALLER ID (CID); CALLER ID CALL WAITING (CID-CW).

Abstract: An optical fiber organizing tray for holding and protecting optical fibers and modular components connected thereto and adapted to be mounted in an enclosure, is symmetrical about both longitudinal and transverse axes. The tray has a centrally located hub member about which fibers are to be wound extending from a substantially planar floor. A peripheral wall extends about the floor member, spaced from the hub member and has spaced keeper bars extending from the wall on one side of the floor to the wall on the other side of the floor. First and second pairs of spaced walls extending higher than the peripheral wall and spaced from the hub member provide storage space for the modular components.

Abstract: A blind equalization technique--the multimodulus algorithm (MMA)--adapts coefficients of an equalizer so as to minimize dispersion of the output samples of the equalizer around piecewise linear contours of a signal space. The MMA technique is illustrated in the context of both square and non-square signal point constellations.