Abstract: A method and apparatus are provided for drawing a self-aligned core fiber free of surface contamination and inserting the core fiber into a cladding material to make an optical fiber preform. Single or multi-mode optical fibers having high quality core-clad interfaces can be directly drawn from the preforms described herein.

Abstract: A speech coding system robust to frame erasure (or packet loss) is described. Illustrative embodiments are directed to a modified version of CCITT standard G.728. In the event of frame erasure, vectors of an excitation signal are synthesized based on previously stored excitation signal vectors generated during non-erased frames. This synthesis differs for voiced and non-voiced speech. During erased frames, linear prediction filter coefficients are synthesized as a weighted extrapolation of a set of linear prediction filter coefficients determined during non-erased frames. The weighting factor is a number less than 1. This weighting accomplishes a bandwidth-expansion of peaks in the frequency response of a linear predictive filter. Computational complexity during erased frames is reduced through the elimination of certain computations needed during non-erased frames only.

Abstract: In a system for providing telecommunications relay service, the delay in assigning an attendant to an established relay session after the text-to-speech conversion process may be controlled by establishing new relay sessions, in response to requests therefor, only if a) less than a predetermined maximum number K of relay sessions have already been established, b) none of the established relay sessions are queued and waiting for an attendant and c) an attendant is available. An established relay session is one that is 1) being served by an attendant, 2) is waiting to be reconnected to an attendant or 3) is in the midst of the text-to-speech conversion process. The value of K is greater than or equal to the number of attendants. It is determined dynamically, as a function of 1) a given set of performance objectives, 2) the current set of traffic characteristics, 3) the current performance characteristics and 4) the resources available at the telecommunications relay service center.

Abstract: A universal wireless radiotelephone communication apparatus is operative in both a first radiotelephone communication system including a first base station having a wide area of coverage, transmitting radiotelephone signals at a first band of frequencies and in a second radiotelephone communication system including a second base station having a localized area of coverage, transmitting radiotelephone signals at a second band of frequencies higher than said first band of frequencies. The second band of frequencies is optimally selected with an offset of less than twice a frequency contained within said first band.

Abstract: Organic thin film transistors having improved properties (e.g., on/off ratio>10.sup.5 at 20.degree. C.) are disclosed. The improved transistors comprise an organic active layer of low conductivity (<5.times.10.sup.-8 S/cm at 20.degree. C., preferably less than 10.sup.-8 or even 10.sup.-9 S/cm). A method of producing such materials is disclosed. Rapid thermal annealing was found to have beneficial results. An exemplary and preferred material is .alpha.-hexathienylene (.alpha.-6T). The improved transistors are expected to find use for, e.g., active liquid crystal displays and for memories.

Abstract: A telecommunications network is arranged to provide equal access to a user of a text telephone device, such that a TDD user may dial directly a desired telephone number, without having to first place a call to a so-called relay center and directing the relay center to dial the desired telephone number.

Abstract: The problem of noise enhancement is eliminated in communications systems by predistorting the amplitude of the transmitted information signal in a manner which compensates for the amplitude distortion introduced in a portion of the communications channel. In the disclosed embodiments, the communications system includes two signal transceivers which communicate with one another through a communications channel. The communications channel includes two-wire subscriber loops adjacent to each signal transceiver with a four-wire transmission path disposed between the subscriber loops. Each transceiver transmits an information signal which, depending on the system noise characteristics, is predistorted to compensate for all or a portion of the amplitude distortion introduced in a subscriber loop adjacent to that signal transceiver. The predistortion necessary to provide such compensation is determined at each transceiver in response to a received narrowband signal at that transceiver.

Abstract: A self-amplified communication system or network (SANE) is disclosed in which one or more regions of an amplifying medium are optically pumped by some or all light sources in the system. The light sources serve as both signal light beam sources and as pump sources providing pump light beams for the amplifying regions. The transmission medium may be an optical fiber, or may be a free-space or planar waveguide transmission medium. The amplifying medium may be in a fiber, waveguide or bulk geometry, and may be local to a pump source, remotely located in the system, or even distributed within the transmission medium. Fixed optical paths with or without transmission of some pump light through an optical amplifier are used. Network topology configurations may be provided, such as point-to-point, star, or ring arrangements. Communication uplinks and downlinks may operate at the same or different wavelengths; and gain may be provided for uplink, downlink, or both.

Abstract: A cluster interface is generated which represents similarities of semantics between segments of code with respect to both the physical constructs of the code and the underlying operations performed by the code. The generated interface represents one or more code segments. Code segments to be analyzed are received by a computer system. Statistical internal information is extracted from each code segment. An external metric is generated which is based on the extracted statistical information. An interface display is created from the external metric which represents similarity relationships between the inputted code segments based on the extracted statistical information.

Abstract: The base layer of high quality spacers, such as those used on the sidewalls of the gate stack of submicron devices (e.g., MOSFETs, EPROMs), are formed as composite, multi-layered structures of silicon oxides or of silicon oxides and silicon nitride.

Abstract: A system for providing a competitive access provider controls specific lines in a remote terminal connected to a monopoly service provider connected directly from the remote terminal to a competitive access switch. In order to control the line or lines in the remote terminal, the competitive access provider switch sends signals via a signaling network to the monopoly service provider. In this manner, a competitive access provider may control a plurality of lines in a remote terminal without having to change a physical plant other than directing one or more DS 1 s or other trunks from the remote terminal to a host digital terminal on the competitive access provider network.

Abstract: A method for simplifying computer protocols is disclosed which offers advantages in reducing the memory and processing requirements for invoking the protocol. In accordance with the present invention, a protocol is represented as a collection of communicating finite machines. The subset of services offered by the protocol desired by a user is also specified as a finite state machine. The method finds the thinned version of the protocol by comparing the finite state machine representation of the protocol with the finite state machine representation of the subset of desired services and keeps only that part of the protocol necessary for providing the desired subset of services.

Abstract: A semiconductor device is provided that includes an optical cavity that is designed to provide a prescribed resonant optical wavelength. The optical cavity includes a mirror structure deposited on top of a substrate and a multi-layer region such as an electroabsorptive region, for example, deposited over the mirror structure. A partial antireflective coating is deposited over the multi-layer region. The mirror structure and the multilayer region have a thickness variation sufficient to yield a resonant optical wavelength that deviates from the prescribed resonant wavelength. The partial antireflective coating has a non-uniform thickness variation that causes the resonant optical wavelength to shift substantially toward the prescribed resonant optical wavelength.

Abstract: Providing capability for increasing, decreasing, or changing types of bandwidth associated with a telecommunication call during the call and through out the call path. New messages can allocate or deallocate bandwidth associated with the call at each intervening switching node through out the call path. All switching nodes of a switching system involved with the resulting call consider the call as a single call. The new messages allow adding video capability to a voice call and, at a still later point in time, removing the video capability from the call. The result is convenience to telecommunication users in that the user is able to utilize any type or amount of bandwidth during a multimedia call. Yet, at any given point in time, the user pays only for the bandwidth that is being utilized.

Abstract: A telecommunication network includes a first telecommunication switch that supports subscribers coupled to the first switch and recognizes a request for call origination by a calling party on an associated communication line. The request for call origination services seeks services from a second switch. A first record in a database coupled to the second switch is located based on the identification of the calling party's line. The second switch is disposed at a hierarchical level above the first switch. A first set of predetermined features is determined based on information contained in the first record. A personal identification number of the calling party is received at the second switch. A second record in a database is located based upon the PIN; the second record is independent from the first record. A second set of predetermined features is determined based upon information contained in the second record.

Abstract: A low noise amplifier (LNA)/mixer/frequency synthesizer circuit for the front end of a RF system. The LNA/mixer/frequency synthesizer circuit is fabricated as an integrated circuit utilizing 0.6 .mu.M CMOS technologies. The LNA within the circuit is provided a bias current from a power supply. Due to the CMOS construction of the LNA, a significant amount of unused power is available within the LNA. The frequency synthesizer requires the same bias current as does the LNA. The frequency synthesizer is directly coupled to the LNA, wherein the unused bias current of the LNA is used to supply the required bias current to the oscillators within the frequency synthesizer. Since the bias current used by the frequency synthesizer is drawn from the surplus of the LNA, a RF system front end is provided that has greatly reduced power requirements. The LNA is coupled to the frequency synthesizer, via an inductor.

Abstract: A telephone or two-way digital paging communication system providing an alternative partial communication format in which an acknowledgement signal is transmitted from a telephone device in response to a received voice or data signal. The communication system is switchable between different types of communication formats including full two-way voice or data service, partial two-way service and one-way pager service. The communication system may be implemented in a cellular network in which a portable cellular telephone is adapted to transmit signals at different transmission rates so as to increase its operable range.

Abstract: A graphic program configuration system is described that allows a user to create complete computer programs. In particular, the present invention improves on the prior art by providing a system and process that permits a subprogram to have an arbitrary number of outlets that may be defined at program configuration time by stimulating the subprogram to create new outlets that facilitate connecting the subprogram to other subprograms. In particular embodiments of the invention the names for the new outlets may either a) be obtained by virtue of the attempted connection of a subprogram to other subprograms or b) be provided direct entry of the outlet name by a user of the program configuration system, e.g., by typing the outlet names on the keyboard. Additionally, in accordance with an aspect of the invention, outlets can be augmented to have one or more constraining parameters that can be used to ensure that only appropriate relationships are established by connections.

Abstract: A wireless base station architecture that is particularly well-suited for providing audio, video and data services. An exemplary embodiment preferably transmits to all of an area those "common services" (e.g., broadcast television) that are intended to be received by multiple recipients throughout the area, but, in contrast, transmits only into a sector those recipient-specific services (e.g., point-to-point voice services, interactive video services) that are intended for less than all of the recipients in the area. In an exemplary embodiment, a demultiplexor directs both broadcast video and recipient-specific or "sectorized" video signals to a video processor, which prepares them for transmission. The demultiplexor also directs sectorized audio signals to an audio processor/RF combiner, which prepares them for transmission.

Abstract: A service control point (SCP) node operates under the control of computer program instructions which interpret message instructions generated by a service administrator. The message instructions provide a hierarchical command structure which permits the SCP node to generate network messages having formats not previously defined as well as changing user specified data. Such network messages are transmitted by the SCP node to identified switches in a telecommunication network in order to determine how a call request, such as an incoming "800" call, will be handled and/or routed by the telecommunication network.