Abstract: A method of solvating metal ions in an aromatic organic liquid. The method includes adding an ammonium salt having an organic acid reagent to the aromatic organic liquid. The organic acid reagent comprises a carboxylate having eight (8) or less carbon atoms. Thereafter, an aqueous solution comprising a metal salt is added to the aromatic organic liquid comprising the ammonium salt and the organic acid reagent. As a result, at least 10% by weight of metal ions is solvated in the aromatic organic liquid.

Abstract: A MEMS optical switch includes a movable cantilevered beam with a waveguide corresponding to one port of the switch. The beam is designed for in-plane motion and can be deflected, e.g., using a three-electrode motion actuator having one electrode on each side of the beam, which itself acts as the third electrode. The beam moves toward a side electrode in response to a voltage difference applied between the beam and that electrode. The beam has two terminal positions, each defined by a stopper. At each terminal position, a bumper portion of the beam is pushed against a corresponding stopper, which aligns the waveguide in the beam with one of two stationary waveguides, each corresponding to a port of the switch. The MEMS switch may be fabricated using a single silicon-on-insulator (SOI) wafer.

Abstract: A method and apparatus for synthesizing speech from text whereby the speech may be generated in a manner so as to effectively convey a particular, selectable style. Repeated patterns of one or more prosodic features—such as, for example, pitch, amplitude, spectral tilt, and/or duration—occurring at characteristic locations in the synthesized speech, are advantageously used to convey a particular chosen style. For example, one or more of such feature patterns may be used to define a particular speaking style, and an illustrative text-to-speech system then makes use of such a defined style to adjust the specified parameter or parameters of the synthesized speech in a non-uniform manner (i.e., in accordance with the defined feature pattern or patterns).

Abstract: A method and apparatus is proposed for use in a communication system in which an optical communications path including a plurality of optical spans, each of the optical spans contributing nonlinear distortions to an optical signal passing there-through includes, providing a dispersion pre-compensation to the optical signal in the optical communications path, such that the limiting nonlinear effect that produces signal distortions for long-haul transmission is suppressed, prior to transmission through a plurality of optical spans, and providing a dispersion post-compensation to the optical signal in the optical communications path after transmission through the plurality of optical spans.

Abstract: An improved method and apparatus for the measurement of the polarization of light uses nonlinear polarimetry. The higher order moments of the E field are measured and then transformed into standard polarimetry parameters yielding the polarization of the light. In a first embodiment, the light to be measured is transmitted through a rotating retarder. The retarder is optically coupled to a fixed analyzer and light is then detected by linear and nonlinear photodetectors. The spectra from the detectors is calculated and transformed, to obtain the polarization. In a second embodiment, the light to be measured is received by an optical fiber comprising a plurality of fiber birefringences to retard the light. Polarization sensitive gratings along the length of the fiber scatter the light, and photodetectors detect the scattered light. Apparatus in two preferred embodiments can perform the inventive method.

Abstract: A method (100) is provided for operating a media gateway (40) in a telecommunications system (A). The gateway (40) provides bearer paths for communication traffic between network segments (20, 30) via contexts (C1 . . . Cn). Each context includes a collection of terminations (T1 . . . Tn) that link the gateway (40) to the network segments and a topology that defines the bearer paths between the terminations within the context.

Abstract: A method for optical layer management of an optical channel in an optical network includes inserting specific data patterns into a frame of an optical signal in the optical channel such that when a framing header is extracted from the optical signal, the specific data patterns are readily identifiable, the specific data patterns being indicative of respective line statuses of the optical channel. Additionally, a method for optical layer management of an optical channel in an optical network includes extracting a frame header from an optical signal in the optical channel and analyzing the optical signal for the presence of previously inserted specific data patterns, the specific data patterns being indicative of respective line statuses of the optical channel.

Abstract: In accordance with the invention, an optical fiber communication system is provided with a tunable linearly chirped Bragg grating in high birefringence fiber for reduction of polarization mode dispersion without increasing chromatic dispersion. A first embodiment using a single grating can be tuned for optimal PMD compensation, optimal chromatic compensation or optimal simultaneous compensation. Alternative embodiments using a plurality of gratings permit simultaneous compensation of both PMD and chromatic dispersion.

Abstract: A method and apparatus for controlling the power level of an optical signal includes detecting the loss of a supervisory signal counter-propagating in an optical fiber.

Abstract: The present invention generally provides optical signal transmission system having an optical signal source, at least one optical signal regenerator in series communication with the optical signal source via an optical signal communications medium, a dispersion module in series communication with the at least one optical signal regenerator via the optical signal communications medium, and a receiver in serial communication with the dispersion module via the optical signal communications medium. The dispersion compensation module inserts an amount of lumped dispersion into the system, which operates to improve the signal transmission characteristics.

Abstract: The invention comprises a method and apparatus for passive optical conditioning and format conversion of RZ optical signals including, but not limited to, conversion from RZ to CRZ or to CSRZ, using a nonlinear device. The invention generates signals that may be optimized to improve transmission performance, receiver performance, and/or spectral efficiency of the optical transmission system. A method for passively generating an optical carrier-suppressed return-to-zero (CSRZ) signal according to the present invention includes, propagating an optical RZ signal through a nonlinear element, the nonlinear element configured to broaden the optical RZ signal such that the optical RZ signal is phase shifted by approximately 3Π/2.

Abstract: Access request transmissions are effected in a wireless communications system by assigning each mobile unit a unique dedicated uplink resource. Specifically, each mobile unit is assigned channel segments with distinct time slot indices and/or waveform indices, where waveforms with distinct indices are orthogonal. A base station can identify the mobile that has made an access request from the dedicated uplink resource. Therefore, no mobile identification number is needed in the uplink request message. Then, the base station can transmit a request response message on a shared downlink resource that may include the identification number of the requesting mobile unit to acknowledge reception of the request. The mobile unit may transmit on a shared uplink resource an acknowledgment of reception of the downlink request response message.

Abstract: A method of transmitting in a synchronous hierarchic network system data is provided using at least a path segment between a first network element (A) and at least a second network element (F) on which a tandem connection monitoring (TC) method is established for monitoring information over the path segment. The method includes suppressing the insertion of all ones caused by the out of multiframe state subsequent to an interruption, distortion or switching operation of the signal transmission path for a predefined time interval.

Abstract: A switch based feature that allows subscribers to adjust their incoming or outgoing audio signal strength. The value of the transmit or receive pad values on the subscriber line card are adjusted to control the strength of the audio signal transmitted to, or received from, the network. The subscriber controls the feature by sending a hook flash to the switch, entering the DTMF keypad feature code and transmit or receive volume parameters, and then returning to the call.

Abstract: A system and method is disclosed for improving diversity in a multiple transmitter or multiple receiver orthogonal frequency division multiplexing (OFDM) system. Signal diversity is improved by introducing phase offsets at the transmitters and/or the receivers. The phase offsets are unique to each transmitter or receiver. The unique phase offsets are applied to individual symbols of the OFDM signal in the frequency domain.

Abstract: A method and apparatus are disclosed for frequency offset estimation in a hybrid in-band on-channel (HIBOC) digital audio broadcasting (DAB) system. The frequency offset estimation algorithm first determines the coarse frequency offset, in terms of integer number of OFDM bin separations between an actual and measured location of a correlated peak, followed by estimation and tracking of the partial (residual) offset in a continuous fashion. A frame is correlated at a first frequency, and then the frequency is shifted by a predefined amount, such as half of the inter-bin frequency amount, &Dgr;f, before correlating again. The measurement with the highest peak of the plurality of frequency values is utilized to obtain the course frequency offset estimate. The partial frequency offset estimation algorithm utilizes phase information contained in reference frequency points in the frequency domain.

Abstract: In accordance with the invention, an optical fiber transmission system is provided with a new method and apparatus to measure PMD and then to use the measurements to control adaptive optical filters that minimize system signal degradation. The measurements provide accurate information to compensate for distortions and thereby permit higher transmission rates. The new technique can obtain phase information without optical heterodyning and without bandlimiting. In a first embodiment, an optical signal transmitter, such as a laser/modulator pair, is driven by a data signal combined with a test signal, in the form of a comb of tones with known relative magnitude and phase relationships. Tunable all pass filters recover phase and magnitude information to control an adaptive filter for precise compensation. In a second embodiment, no changes are made to the transmitted signal.

Abstract: An out-of-band ranging technique is automatically initiated at a customer premises equipment unit when the equipment is installed, when power is restored after a power failure or interruption, upon verification of the equipment, upon reconnection after a disconnection of the equipment or the like. To this end, an out-of-band tone is employed that is automatically transmitted when the customer premises equipment that transmits the TDMA signal is powered ON, or transmitted in response to a specific command generated locally or remotely. Specifically, when ranging is being effected the customer premises equipment generates and transmits the out-of-band ranging tone until a message is received from a remote terminal indicating that the transmission of the ranging tone be terminated. The loop delay being determined is the delay interval between transmission of the termination message and detection that transmission of the ranging tone has terminated.

Abstract: A line card for supporting both circuit switching and packet switching is provided. The line card interfaces asynchronous communications and synchronous communications using a ATM switch and a Synchronous to Asynchronous Converter-Time Slot Interchange (SAC-TSI) that allows TDM traffic to be routed into the ATM fabric of the ATM switch. The line card supports video, voice and data communications. The line card further supports ATM, ethernet and frame relay communications.

Abstract: A node for use in a multi-source ring transmission system includes a controller and storage. Identifiers, such as ring addresses, for the relative first and relative last source nodes within the ring transmissions system are stored within the node's storage, in a squelch table for example. The node's relative first source node is the source node farthest upstream from the node and the node's relative last source node is the node that is farthest downstream from the node. The node blocks communications whenever both its relative first source node and its relative last source node fail.