Abstract: Methods and systems for performing handwriting recognition which include, in part, application of stochastic modeling techniques in conjunction with language modeling. Handwriting recognition is performed on a received data set, which is representative of a handwriting sample comprised of one or more symbols. Recognition is performed by selectively segmenting the data set into one or more strokes utilizing an evolution grammar for identifying each one of the strokes among one or more alternatives. Each one of the strokes represents a segment of the handwriting sample. The identified strokes are evaluated as a stroke sequence, representative of one or more of the handwriting sample's symbols, to identify the handwriting sample.

Abstract: A boost converter module, a method of manufacturing the module and a power converter employing one or more of the same. In one embodiment, the boost converter module includes: (1) a power switch, (2) first and second snubber diodes series-coupled between the power switch and a converter output, (3) a snubber capacitor and a boost diode series-coupled across the second snubber diode and (4) an encapsulant substantially surrounding the power switch, the first and second snubber diodes, the snubber capacitor and the boost diode to join the power switch, the first and second snubber diodes, the snubber capacitor and the boost diode into an integrated package, the integrated package having: (4a) a control input coupled to the power switch, (4b) a power input coupled to the power switch, (4c) a snubber inductor input, coupled to a node between the snubber capacitor and the boost diode and (4d) a power output coupled to the converter output.

Abstract: A cladding-pumped fiber structure, suitable for use as a laser, provides for efficient clad-to-core energy transfer. The outside interface of the pump-clad is constructed from a rod-shaped preform by local melt-displacement using an open flame.

Abstract: A thick holographic recording medium suitable for use in multiplex holography is prepared from a solution of a bi-functional oligomer and a mono-functional monomer. Precuring, possibly at the same radiation wavelength used for recording, cross-links the oligomer, thereby creating a host for the recording monomer.

Abstract: An apparatus for performance improvement of a digital wireless receiver comprises a processing circuit for processing a plurality of received signals and providing a processed signal, wherein a plurality of weights is applied to the plurality of received signals producing a plurality of weighted received signals. The plurality of weighted received signals are combined to provide the processed signal. A weight generation circuit generates the plurality of weights wherein weights are based on a ratio of a desired signal, a noise signal and an interference signal.

Abstract: A DC coupled burst mode optical receiver circuit having improved sensitivity and improved dynamic range. The output of the receiver's photodiode is single endedly amplified by a main preamplifier and the main preamplifier's output is then converted, using an operational amplifier, e.g., with a gain of 1, to a differential signal which swings symmetrically around a threshold level. More specifically, the output of the main preamplifier is connected to one input of the operational amplifier. The output of a tracking preamplifier, which is identical to the main preamplifier, is coupled to the other input of the operational amplifier. The output of the tracking preamplifier is used to match the DC voltage of the main preamplifier, e.g., by being noise-free and by tracking changes in supply voltage, temperature, and the like. It is used to set the DC reference voltage for the standard operational amplifier functions.

Abstract: The present invention is a system and method for routing cells in a wireless communications network, wherein the communications network includes a plurality of switching nodes and the cells are routed according to destination-rooted virtual path identifier (VPI) trees. The present invention includes a routing protocol for determining preestablished VPI trees rooted at each destination node. The routing protocol manages the routes of these trees, while ensuring that there are at least two VPI trees from each source to each destination for reliability reasons, and that each destination node has multiple VPI trees for load-balancing reasons. The routing protocol includes an off-line procedure for the determination of the initial VPI trees. In order to handle changes in network traffic and conditions, the routing protocol updates the routes of the VPI trees in a dynamic and distributed fashion. These update procedures are triggered by congestion, link/node failures and link/node additions.

Abstract: A synchronous rectifier for use with a clamped-mode power converter uses in one embodiment a hybrid rectifier with a MOSFET rectifying device active in one first cyclic interval of the conduction/nonconduction sequence of the power switch and a second rectifying device embodied in one illustrative embodiment as a low voltage diode rectifying device active during an alternative interval to the first conduction/nonconduction interval. The gate drive to the MOSFET device is continuous at a constant level for substantially all of the second interval which enhances efficiency of the rectifier. The diode rectifier device may also be embodied as a MOSFET device. The subject rectifier may be used in both forward and flyback power converters.

Abstract: Decision feedback equalization is used in a communication system which employs coded modulation, such as trellis coded modulation. The transmitted stream of signal points includes first signal points that were generated using a particular coded modulation scheme interspersed with second signal points that were generated without the using of coding, and estimated intersymbol interference components for the second signal points are generated in response to tentative decisions as to the first signal points formed by the Viterbi decoder. Rather than forming immediate final decisions as to the second signal points, there is formed a tentative decision for each one of the second signal points associated with each Viterbi decoder state using an estimated intersymbol interference component provided from a decision feedback equalizer associated with that state. Each second-signal-point tentative decision is used to extend the surviving path for the associated state and to also update its path metric.

Abstract: A partial optical coupler of the present invention comprises first, second and third walk-off devices having a non-reciprocal polarization interchanger unit positioned between the first and second and the second and third walk-off devices. The first and third walk-off devices are matched in terms of the amount of walk-off and the direction of walk-off. A further embodiment includes a reflector which allows the light beam to pass through each walk-off device and each non-reciprocal polarization interchanger unit twice.

Abstract: A passive locator and method for a wireless communication system. The locator (56) at base station (12) determines the position and trajectory of wireless terminal (22). The passive locator (56) adjusts azimuthal and elevational angles of a directional antenna (58) until a relative maximum power is detected in the signal transmitted from the wireless terminal (22). A processing circuit (60) determines the trajectory of the wireless terminal (22) by generating and analyzing data that represents the Doppler effect on the signal from the wireless terminal (22).

Abstract: A method of mounting a power semiconductor die on a substrate, a package for the die and a power supply including the package. The die has a first power terminal on a first surface thereof and a second power terminal on an opposing second surface thereof. The method including the steps of: (1) forming an electrically-conductive, mechanical bond between the first surface and a first location on the substrate, the mechanical bond electrically coupling the first power terminal to the substrate and (2) soldering an elongated electrically conductive strap to the second surface and a second location on the substrate, the conductive strap composed of a material having an electrical resistivity at most about 5.0.times.10-.sup.8 ohm-meters (.OMEGA.-m) and forming a low impedance path between the second power terminal and the second location.

Abstract: Optoelectronic devices such as photodetectors, modulators and lasers with improved optical properties are provided with an atomically smooth transition between the buried conductive layer and quantum-well-diode-containing intrinsic region of a p-i-n structure. The buried conductive layer is grown on an underlying substrate utilizing a surfactant-assisted growth technique. The dopant and dopant concentration are selected, as a function of the thickness of the conductive layer to be formed, so that a surface impurity concentration of from 0.1 to 1 monolayer of dopant atoms is provided. The presence of the impurities promotes atomic ordering at the interface between the conductive layer and the intrinsic region, and subsequently results in sharp barriers between the alternating layers comprising the quantum-well-diodes of the intrinsic layer.

Abstract: Apparatus and methods are provided for generating an output signal representing a selectively reduced coding rate for use in compressing a digital signal. The digital signal includes a plurality of digital sets wherein at least one of the digital sets are non-unique. A current coding rate and a threshold coding rate compared to determine whether the current coding rate satisfies a predetermined criteria. In response to the determination, at least one of the digital sets are selectively discarded, a rate difference resulting from selectively discarding at least one of the plurality of digital sets is determined, and the current coding rate is recalculated using the determined rate difference.

Abstract: A controllable magnetic field generator applies a magnetic field to a transistor device at a particular orientation for producing a corresponding Lorentz force on the flow of carriers in the device to advantageously deflect the carriers to facilitate performance of a corresponding desired circuit function. Such a component arrangement is useable in a variety of circuit configurations for performing different circuit functions with a reduced number of devices and complexity relative to conventional circuit configurations. Exemplary circuit configurations for signal mixers, differential amplifiers, switches, and multiplexers and demultiplexers are possible using as little as one or two devices. According to another aspect of the invention, an inductor coil is used for the magnetic field generator and is formed on a substrate containing the transistor device to provide a component arrangement having relatively compact dimensions.

Abstract: A switch arrangement that employs features which already exist in the switch to otherwise realize capabilities for wired terminals employing the same features to realize capabilities for wireless terminals. In particular, one capability that is necessary for wireless operations is the ability to track the terminals as they roam anywhere within the permissible area. This capability is achieved herein through the "registration" feature of the switch that is designed to handle wired terminals. Tracking is achieved with this feature by causing all wired terminals to send a similar information string, at regular intervals. As the wireless terminal roams, it is acquired by different base stations that are connected to different line ports of the switch and the base stations, effectively, inform the switch of the wireless terminal's wherabouts. Tracking across different switches is also achieved through the registration feature.

Abstract: A network hub system (200) is connected to a communications cloud (18) as well as messaging systems (202), (204), (206) and (208). A public access port (212) interacts with a public virtual messaging system (202a). A private access port (214) interacts with a private virtual messaging system (202b). Address translation tables are used to provide for identification of members of messaging communities which allow for the implementation of virtual private networks connected to hub system (200) and other hubs.

Abstract: Briefly, in accordance with one embodiment of the invention, a method of compensating for Doppler error in a wireless communications system employing Viterbi decoding comprises the steps of: for each signal sample in a first predetermined-sized grouping of received signal samples, performing a parallel Viterbi update and short symbol decode; and for a second predetermined-sized grouping, forming by pipeline processing an estimate of the Doppler error in accordance with the parallel short traceback decoding performed for the first grouping, and adjusting each signal sample in the second grouping in accordance with the estimated Doppler error.Briefly, in accordance with another embodiment of the invention, a Viterbi traceback reconstructed signal sample index comprises: a state counter, a traceback shift register (TBSR); a signal reconstruction table; and a comparator coupled in a configuration so as to provide the sign bit to the TBSR from a comparison of binary digital signals.

Abstract: For use in a system capable of communicating in either analog or digital wireless infrastructures, an intermediate frequency ("IF") amplifier and method that allows the system to process both analog and digital input signals in a common amplifier stage. The system includes: (1) first and second amplifiers, having parallel-coupled signal inputs and gains that combine to equal a constant total value, that receive an input signal and produce therefrom first and second output signals that are each a function of an applied gain signal, (2) a combinatorial circuit, coupled to the first and second amplifiers, that derives from the first and second output signals a combined signal that is a function of a power of the input signal and substantially immune to changes in the applied gain signal and (3) a gain control circuit, coupled to the first and second amplifiers, that holds the gain signal constant when the input signal is analog and varies the gain signal when the input signal is digital.

Abstract: Two methods are disclosed for storing multimedia data that reduces the amount of disk I/O required by the system and cache misses experienced by the system. The first method determines the future access of each data buffer in a cache memory. Once the future of the data buffer is determined, the data buffer with the maximum future is allocated to store new blocks of data. The method approximates an optimal method of data buffer allocation, by calculating the future of a data buffer, relative to clients that will access the data buffers. The second method orders the clients based on the increasing distance of each client from the previous client; clients release the buffers in this order into a LIFO queue; if a buffer is selected to load a new block of data, the buffer at the head of the LIFO queue is selected.