Abstract: A speech synthesis method employs an acoustic element database that is established from phonetic sequences occurring in an interval of a speech signal. In establishing the database, trajectories are determined for each of the phonetic sequences containing a phonetic segment that corresponds to a particular phoneme. A tolerance region is then identified based on a concentration of trajectories that correspond to different phoneme sequences. The acoustic elements for the database are formed from portions of the phonetic sequences by identifying cut points in the phonetic sequences which correspond to time points along the respective trajectories proximate the tolerance region. In this manner, it is possible to concatenate the acoustic elements having a common junction phonemes such that perceptible discontinuities at the junction phonemes are minimized. Computationally simple and fast methods for determining the tolerance region are also disclosed.

Abstract: The invention relates to a multiwavelength add/drop multiplexer for use in an optical fiber communication system having a main optical fiber. The multiplexer includes an optical element, in the form of an optical circulator, arranged to direct substantially all of the light transmitted in a predetermined direction along the main optical fiber into a branch optical fiber regardless of wavelength. The branch optical fiber includes a transmission filter, in the form of a Fabry-Perot filter, arranged to transmit light of a predetermined wavelength and reflect the non-transmitted light back towards said main optical fiber for continued propagation along said main optical fiber. The multiplexer also includes a receiver for receiving the transmitted light, and further includes a transmitter arranged to transmit optical data signals along said branch optical fiber, through said transmission filter and towards said optical element, for propagation along said main optical fiber.

Abstract: Bilevel textual images are compressed by segmenting the image into marks (401) and then coding each mark using a soft pattern matching method. Each mark is compared (403) with the marks in a library of marks and if an acceptable match is found (404), the index of the matching mark is coded (412). Each pixel in a current mark is then coded using a statistical coder that codes each pixel based on the value of the pixel and a set of probabilities of all sample values based on a context that consists of pixels in the current mark and pixels in the matching mark (414, 415, 416, 417). In order to reduce the overall bit count of the image, pixels which are poorly predicted (i.e., pixels black ?or white! in value, but whose context makes them more likely to be white ?or black!)) (705) are color-reversed (706, 709) prior to coding, if so doing will not perceptibly alter a reconstructed image (708).

Abstract: A scheduling mechanism for satisfying specified Quality of Service (QoS) guarantees for each VC of an end-point host in an ATM network. The scheduling mechanism includes a time slot ring, a VC table and a pending queue. The time slot ring is an array, wherein each element represents a time slot. Each slot contains a pointer which contains the virtual channel identifier (VCID) which is to be serviced in this time slot. The VC table is an array of all the VC descriptors. The pending queue is used for queuing a new VC and also at a later time, when the scheduler is unable to find a time slot for a VC it is queued in the pending queue. The scheduler reads and processes one slot at a time at the maximum speed that the physical link will allow. The scheduler circularly services the slots in the ring continuously and a current slot pointer (CSP) points to the slot being serviced.

Abstract: A technique for packet-switching suitable for interference-limited wireless communication systems is provided. Long bursty packets of data are broken into shorter units or packet-slots. This advantageously provides for averaging and minimizing interference in time--one of the requirements for achieving high system capacity in interference-limited systems. Transmit-start times and durations of packet slots are controlled by packet-slot distribution patterns. The patterns are representable by unipolar binary codes/sequences whose properties are based on number-theoretic principles. The technique minimizes the time variance of composite interference due to simultaneous transmissions of numerous signals over the same frequency channel. By minimizing the variance of overall interference, this technique satisfies the demand of multi-media traffic and also increases system capacity in a fading multipath environment.

Abstract: We have invented methods of and devices for introducing unequal error protection into spread spectrum communication systems. One embodiment of the invention addresses certain inefficiencies of the standard known as IS-95 used, for example, in some mobile direct sequence code division multiple access ("DS-CDMA") phone systems. The invention allows for increased system capacity and/or improved quality. More specifically, spread spectrum multiple access ("SSMA") coding may be combined with the concept of unequal error protection ("UEP"), resulting in an UEP SSMA coding process. IS-95, in order to make significant portions of a signal highly immune to errors, has imposed the same high degree of error immunity on less significant portions of the signal (when, in fact, a lower degree would suffice) and, thus, wastes bandwidth. The present invention's coding process (i.e., UEP SSMA) utilizes bandwidth in a closer to optimal manner than known methods.

Abstract: The invention is a surge protector which can provide voltage and current protection in coaxial cable systems. The protector includes a central conductor which is coupled in series with a variable resistance, and a voltage surge arrestor which is coupled between the conductor and the housing of the protector. A capacitor may also be coupled in parallel with the resistor. The protector provides both an ac and dc signal path.

Abstract: A voice activated device using speaker independent speech recognition is capable of receiving from a remote location the phonetic spellings needed for speech recognition in the device. The phonetic spellings, as well as additional application data, are communicated to the voice activated device from the remote location and stored in the device. A user can then speak voice commands which are intercepted by the device where local processing of the voice commands takes place. The device makes available to the user extensive information pertaining to multiple network services or applications. The information may be communicated to the user by voice or via other communication media.

Abstract: An improved modulator and methods for making the modulator are disclosed. A membrane, preferably circular in shape, is formed over a region of a substrate in such a way that a gap results between the membrane and substrate forming a modulator cavity. The membrane forms a continuous surface over the cavity. In particular, the membrane is not supported by discrete support arms, but rather extends beyond the modulator cavity. Preferably, holes are formed in the membrane to aid in damping its motion and to allow access to underlying layers during modulator formation. According to the method, the modulator is formed by forming a means for creating a gap between the substrate and the membrane, forming a membrane, forming a lateral conduit to aid in removing the means for creating the gap and, finally, by removing the means for creating the gap.

Abstract: It has been found that surface reactions with basic materials such as amines found in the processing environment during lithographic processing contribute to a loss of linewidth control for resists such as chemically amplified resists. This loss in linewidth results from the reaction of the acid generated by exposing radiation with, for example, the amine resulting in a lack of chemical reaction where such reaction is desired. The problem is solved in one embodiment by employing an acid containing barrier layer on the resist.

Abstract: A system for including audio data within a video signal. The number of frames of video data transmitted is reduced, thereby allowing greater time for each individual frame, thereby allowing the breezeway of each line of each frame to be lengthened. The breezeway resides between the horizontal synch pulse for the line, and the color burst signal. Samples of digitized audio are placed into the breezeways.

Abstract: An optical fiber cable includes one or more component cables. In one embodiment, the component cable has an elongated central aramid yarn member surrounded by at least one, and preferably six, optical fibers. An aramid yarn layer surrounds and contacts the optical fibers, and a plastic jacket envelopes and contacts the aramid yarn layer. In a second embodiment, the component cable includes optical fibers, preferably twelve in number, embedded in aramid fibers. A plastic jacket in contact with the aramid fibers, encloses the aramid fibers with its embedded optical fibers. In the cable of this invention, component cables of the first and/or second embodiments are wound about an elongated, central strength member with a reverse-oscillated lay. An outer jacket encloses and holds the reverse-oscillated lay of the component cables. The invention also includes a system for manufacturing the cables of this invention.

Abstract: Methods and systems for controlling data transfer operations during a communication session between a transmitter and at least one receiver provide that data packets which have been stored at the receiver memory before a disconnect occurred remain stored in therein in the presence of the disconnect to avoid the need for retransmitting data packets upon re-establishment of a communication link. Data representative of those data packets already stored at the receiver memory is maintained for purposes of synchronizing data packet transmission from the transmitter for completing data file transfer. Data control instructions for implementing storage of data packets and tracking the progression of data packet transmissions when a disconnect occurs may suitably included in an existing protocol layer of a communication system or as an additional protocol layer added to the operating system of the communication system.

Abstract: A destination telecommunication switch receives a request to establish a call to a first party served by the switch. The request includes call type data that identifies the party originating the call request as one of a plurality of call categories. A first record associated with the first party is read from a database. The first record includes at least one set of data which defines a call category and a corresponding call processing technique to be utilized for the call category. The switch processes the incoming call in accordance with the predetermined call category handling if the incoming call is identified by call category data in the database.

Abstract: A dual-ring, multiplexed-communications network to deliver protected service to nodes where protection is required, while simultaneously other nodes of the same network, where only unprotected commodity service is needed, are not burdened with the cost of duplicated optical and electronic equipment.

Abstract: Active circuitry is placed under the bond pads in an integrated circuit having at least three metal levels. The metal level adjacent the bond pad level acts as a buffer and provides stress relief and prevents leakage currents between the bond pad and underlying circuitry.

Abstract: In a preferred embodiment, a low distortion power sharing amplifier network capable of amplifying a plurality of input signals includes a plurality of amplifiers, each for amplifying an approximately equal amount of RF signal power. The power sharing arrangement prevents any one of the amplifiers in the network from operating too deep into saturation even when the plurality of input signals vary widely in power. Distortion is reduced by coupling at least one feed-forward loop to the amplifier network.

Abstract: In a multimedia communications system where bandwidth of an access facility is limited, the bandwidth is partitioned into three bands dedicated to audio, video and data traffic, respectively, in accordance with blocking probabilities associated with the respective media types. The value of each blocking probability is selected pursuant to the relative importance of the associated media type in a multimedia service. With the blocking probabilities in place, the dominance of traffic of a particular media type, which may be relatively unimportant in the service, would not cause blocking of traffic of other media types, which may be relatively important.

Abstract: A communications system is designed to monitor voice communications signals for an initial end-to-end communications link which is comprised of a) a wireless segment which connects a wireless network to a wireless end-user apparatus, and b) a second segment which connects a communications end-user device to the wireless network. When the system detects that the wireless segment is inoperative, it inhibits the release of the second segment. Thereafter, the system sets up a subsequent wireless segment which extends from the wireless network to the wireless end-user apparatus. The subsequent wireless segment is then bridged to the second segment to form a new end-to-end communications link to restore connectivity between the wireless end-user apparatus and the communications end-user device.

Abstract: A digital audio broadcasting (DAB) system includes a radio-frequency (RF) transmitter and a corresponding RF receiver. The RF transmitter formats a DAB signal into a sequence of frames, each frame having a header comprising a predefined grouping of psuedo-random number sequences comprising 100 symbols. Of these 100 symbols, 86 symbols of the header are used for frame synchronization and channel sounding (for characterization of a communications channel), while the remaining 14 symbols are used for interleaver and data synchronization in an interleaved fashion.