Patents Issued in May 6, 2004
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Publication number: 20040085975Abstract: The invention is a system for interfacing a GR-303 system with a broadband system. The broadband system can be an ATM system. The invention can process the GR-303 signaling to select ATM connections and then interwork the GR-303 connections with the selected ATM connections. The invention can interwork GR-303 signaling and SS7 signaling. The invention can also process SS7 signaling to select GR-303 connections and then interwork ATM connections with the selected GR-303 connections.Type: ApplicationFiled: October 9, 2003Publication date: May 6, 2004Applicant: SPRINT COMMUNICATIONS COMPANY, L.P.Inventors: Joseph Michael Christie, Michael Joseph Gardner, Tracy Lee Nelson, William Lyle Wiley, Albert Daniel DuRee
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Publication number: 20040085976Abstract: In a DOCSIS based satellite gateway data is transmitted over a single downstream channel, at different throughput rates. Data destined for each subscriber/receiver is assigned a throughput rate depending upon the downstream signal quality of that subscriber/receiver. To accomplish this, the downstream DOCSIS MAC data is parsed to extract DOCSIS packets. The DOCSIS packets are then loaded into packet queues based on an identifier within such packets such as the MAC destination address or SID. Each of the queues represents a bandwidth efficiency or throughput rate that can be currently tolerated by specific subscribers based on the current signal quality being experienced at the subscriber location. A PHY-MAP describing the downstream data structure to be transmitted and inserted into the downstream data. Data is extracted from the packet queues in queue blocks as defined by the PHY-MAP.Type: ApplicationFiled: December 12, 2002Publication date: May 6, 2004Inventors: Mark Dale, Anders Hebsgaard, David Hartman, Alan Kwentus, Steven Jaffe, Kelly Cameron, Stephen Krafft, Alan Gin, Jen-Chieh (Jack) Chien, Dorothy Lin, Rocco Brescia, Joyce Wang
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Publication number: 20040085977Abstract: Provided are a method, system, and program for processing packets of data. An available packet buffer in memory is allocated to a received packet, wherein the received packet is stored in the allocated packet buffer. A determination is made as to whether a number of available packet buffers is less than a first threshold. A further determination is made as to whether the number of available packet buffers is less than a second threshold if the number of available packet buffers is not less than the first threshold. An operation is initiated to copy the received packet from the allocated packet buffer to a copy buffer if the number of available packet buffers is less than the second threshold.Type: ApplicationFiled: October 30, 2002Publication date: May 6, 2004Applicant: Intel CorporationInventor: Daniel R. Gaur
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Publication number: 20040085978Abstract: A system is provided for prioritizing and queuing traffic from a plurality of data streams. The system includes a queuing structure, processing circuitry, and a search engine. The queuing structure has a plurality of queues. The search engine is implemented on the processing circuitry and is configured to search and edit the queues in order to manage traffic at a given instance in time by traversing each of the queues in a predetermined manner to identify and remove eligible entries from each queue that need to be transmitted. The traffic was previously classified as to type and traffic elements were previously loaded onto selected queues with other traffic elements having a similar traffic type. A method is also provided.Type: ApplicationFiled: November 4, 2002Publication date: May 6, 2004Inventors: Keith Michael Bly, C. Stuart Johnson
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Publication number: 20040085979Abstract: A multiple input/output-queued(MIOQ) switch is presented. This MIOQ switch comprises a (k,m)-dimensional crossbar fabric having k ingress lines and m egress lines; N input buffers at each input; M output buffers at each output; N×k interconnection networks each of which is able to move a packet from each input to one of the k egress lines; and m×M interconnection networks each of which is able to move the arrived packet at output from the m egress lines to one of the M(wherein M is m or N) output buffers. The multiple input/output-queued(MIOQ) switch according to the present invention requires no “speed-up”. Performance matches the performance of an output-queued switch.Type: ApplicationFiled: June 9, 2003Publication date: May 6, 2004Applicant: Seoul National University Industry FoundationInventors: Hyoung-Il Lee, Seung Woo Seo
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Publication number: 20040085980Abstract: A system for maintaining a transaction cache consistency in a mobile communication network is provided. The system comprises: a mobile server for periodically broadcasting an invalidation report (IR) message; and a mobile client for updating data stored in a transaction cache based upon information included in the IR message, and for confirming execution of a transaction.Type: ApplicationFiled: July 2, 2003Publication date: May 6, 2004Applicant: LG Electronics Inc.Inventor: Sang Keun Lee
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Publication number: 20040085981Abstract: A wireless communication system has a queue information search unit for searching a queue-status information provided in a packet unit, a communication priority decision unit for deciding communication priority of external devices based on the queue-status information, giving a higher priority to the external device having a greater number of packets in queues, a communication initiation unit for initiating a communication with the external devices according to the communication priority, a counter for counting the number of times that the communication is initiated for each of the external devices, and a comparator for comparing a counter value of a first external device that corresponds to a transmitted data with a counter value of a second external device that has a maximum counter value. Accordingly, when the wireless communication device transmits and receives data with respect to the plural wireless communication devices, both high throughput and high fairness can be guaranteed.Type: ApplicationFiled: July 17, 2003Publication date: May 6, 2004Applicant: SAMSUNG ELECTRONICS CO., LTD.Inventors: Tae-Jin Lee, Kyun-Hyon Tchah, Ki-Soo Chang, Oh-Seok Kwon, Yang-Ick Joo, Jong-Soo Oh, Yong-Suk Kim, Doo-Seop Eom
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Publication number: 20040085982Abstract: A system and method for managing traffic in a communication system assigns multiple links in a system to a queue. The queue is formed from one or multiple memories and a queue assignment unit assigns banks in the queue to one or more links. The queue assignment also writes data in the banks of specific links through a write control signal. A signal detection unit detects availability of a line interface unit, and a data control unit that reads data from the queue and writes it in the line interface unit. Through this structure, a faster and more efficient data transmission system is formed.Type: ApplicationFiled: October 2, 2003Publication date: May 6, 2004Applicant: LG Electronics Inc.Inventor: Jeong Hoon Choi
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Publication number: 20040085983Abstract: A method and structure for performing a delayed counter increment is provided. The method and structure allows a counter decision to be modified based upon what the computer system hardware does with the data packet. Subsequent to the generation of a counter command, the processing of the data packet may change: for example, the data packet may be discarded instead of forwarded. Accordingly, the counter increment instruction is changed. A delayed counter increment will perform the actual counter update after the processing of the data packet is completed. In one embodiment of the invention, the counter update action is modified depending upon whether the data packet is forwarded or discarded, and a different counter is selected to be updated. This solves a problem that sometimes the forwarding code is unable to determine if some independent action may later discard a data packet.Type: ApplicationFiled: October 7, 2003Publication date: May 6, 2004Applicant: International Business Machines CorporationInventors: Brian Mitchell Bass, Gordon Taylor Davis, Marco C. Heddes
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Publication number: 20040085984Abstract: Systems and methods that provide receive queue provisioning are provided. In one embodiment, a communications system may include, for example, a first queue pair (QP), a second QP, a general pool and a resource manager. The first QP may be associated with a first connection and with at least one of a first limit value and an out-of-order threshold. The first QP may include, for example, a first send queue (SQ). The second QP may be associated with a second connection and with a second limit value. The second QP may include, for example, a second SQ. The general pool may include, for example, a shared receive queue (SRQ) that is shared by the first QP and the second QP. The resource manager may provide, for example, provisioning for the SRQ and may manage the first limit value and the second limit value.Type: ApplicationFiled: October 17, 2003Publication date: May 6, 2004Inventor: Uri Elzur
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Publication number: 20040085985Abstract: A network device architecture and associated methods are generally described.Type: ApplicationFiled: October 30, 2002Publication date: May 6, 2004Inventors: Gerald Lebizay, David W. Gish, Brian E. Peebles
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Publication number: 20040085986Abstract: The aim of the invention is to achieve a greater flexibility when transmitting data according to a hybrid ARQ method, (preferably when used in a mobile radio system. To this end, a channel-coded bit stream is divided into at least one first bit stream (A) and one second bit stream (B, C), whereby these parallel bit streams (A-C) are each subjected to a separate bit rate matching, and the resulting bits of the individual bit streams (A-C) are subsequently combined with one another once again in order to transmit in a data packet or in a repeat data packet that is requested on the receiver side.Type: ApplicationFiled: August 19, 2003Publication date: May 6, 2004Inventors: Jurgen Michel, Bernhard Raaf
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Publication number: 20040085987Abstract: A modem for use in Digital Subscriber Line communications transmits and receives data over the local subscriber loop in common with voice information over the loop, while avoiding the need for voice/data splitters. The modem responds to disruptions associated with “disturbance events” such as on-hook to off-hook transitions and the like by rapidly switching between pre-stored channel parameter control sets defining communications over the loop under varying conditions. In addition to changing parameter control sets responsive to a disturbance event, the modem may also change transmission power levels and other system parameters such as frequency domain equalizer characteristics. Further, provisions are made for reduced bandwidth communications under selected conditions.Type: ApplicationFiled: August 7, 2003Publication date: May 6, 2004Applicant: AWARE, INC.Inventors: Richard W. Gross, John A. Greszczuk, David M. Krinsky, Marcos Tzannes, Michael A. Tzannes
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Publication number: 20040085988Abstract: A downhole telemetry system employing code division multiple access (CDMA) is disclosed. In one embodiment, the downhole telemetry system comprises one or more downhole transmitters and an uphole receiver. Each of the downhole transmitters transmits a corresponding uplink signal which is generated using amplitude modulation of corresponding code word signals. The code word signals are orthogonal to each other, and the transmitters may be configured to adjust the timing to assure synchronous arrival of the various uplink signals at the receiver. Each of the transmitters may be allocated a different number of code words when it is desired to allow for unequal bandwidth requirements. Such allocation is preferably dynamic. Additional modulation techniques may be employed with CDMA, including frequency division multiplexing, time division multiplexing, and frequency re-use.Type: ApplicationFiled: November 6, 2002Publication date: May 6, 2004Applicant: Halliburton Energy Services,Inc.Inventors: Wallace R. Gardner, Roger L. Schultz, Beegamudre N. Murali, Manfred G. Prammer
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Publication number: 20040085989Abstract: The digital symbols of a sequence are assigned to respective positions in successive timeslots, according to a predetermined slot format. In a plurality of timeslots, a symbol of the sequence is replaced by a substitution symbol carrying additional information. A signal representing the sequence of symbols, which is divided into the timeslots, is transmitted on a communication channel. The production of the sequence includes an interleaving having an interleaving period longer than a timeslot, generally performed after a channel coding. The position of the substitution symbols in the timeslots which include them is varied, in order to optimize the performances of the transmission chain.Type: ApplicationFiled: December 23, 2002Publication date: May 6, 2004Applicant: Nortel Networks LimitedInventors: Sarah Boumendil, Evelyne Le Strat, Bastien Massie
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Publication number: 20040085990Abstract: A system and method provide enhanced services for a call that is transported from a communication device through an asynchronous transfer mode system. The call has user communications in asynchronous transfer mode cells and call signaling. A signaling processor receives the call signaling and processes the call signaling to determine a connection to a service platform. The signaling processor transports a processor control message designating the selected connection. An asynchronous transfer mode interworking unit receives the user communications from the communication device and the processor control message from the signaling processor. The asynchronous transfer mode interworking unit converts the user communications from the asynchronous transfer mode cells to a format compatible with the service platform and dynamically transports the user communications to the service platform in real time. The service platform processes the user communications.Type: ApplicationFiled: October 8, 2003Publication date: May 6, 2004Applicant: SPRINT COMMUNICATIONS COMPANY, L.P.Inventors: Joseph Michael Christie, Joseph S. Christie, Jean M. Christie, Tracy Lee Nelson
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Publication number: 20040085991Abstract: A method for the allocation of resources in a communications system comprising several stations including defining a graph of competition between the different stations, and assigning time intervals to each station in making successive passages on all the stations and carrying out, at each passage and for each station, wherein E is an interval of given time interval numbers, and n is the smallest natural integer that does not belong to the interval E. If it is not the first passage AND if n>Nmax, then no time interval whatsoever is added to the station Si. If it is the first passage OR if n=<Nmax, then n is added to the time intervals assigned to Si. These steps are executed so long as a time interval is added.Type: ApplicationFiled: October 29, 2003Publication date: May 6, 2004Applicant: THALESInventor: Francois Paul
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Publication number: 20040085992Abstract: A technique is disclosed for maintaining fairness in scheduling order while communicating multiple streams on a shared-communications medium. Simulations have shown that the scheduling order of when stations transmit is of great importance. Typically, the scheduling order of multiple streams of message traffic on a shared-communications medium is unfair, at least in the short term. Streaming applications, however, demand fairness in short term scheduling. Otherwise, the intermediate delays would be unacceptably uneven. To address the delay problems associated with multiple streams on a shared-communications medium, each station transmits a portion of a coordinated flow. After transmitting the portion, the station self-imposes a restriction interval, during which time, the station cannot contend again for the purpose of transmitting the next portion of the coordinated flow.Type: ApplicationFiled: April 23, 2003Publication date: May 6, 2004Inventor: Maarten Menzo Wentink
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Publication number: 20040085993Abstract: A technique is disclosed for maintaining fairness in scheduling order while communicating multiple streams on a shared-communications medium. Simulations have shown that the scheduling order of when stations transmit is of great importance. Typically, the scheduling order of multiple streams of message traffic on a shared-communications medium is unfair, at least in the short term. Streaming applications, however, demand fairness in short term scheduling. Otherwise, the intermediate delays would be unacceptably uneven. To address the delay problems associated with multiple streams on a shared-communications medium, each station transmits a portion of a coordinated flow. After transmitting the portion, the station self-imposes a restriction interval, during which time, the station cannot contend again for the purpose of transmitting the next portion of the coordinated flow.Type: ApplicationFiled: April 23, 2003Publication date: May 6, 2004Inventor: Maarten Menzo Wentink
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Publication number: 20040085994Abstract: Methods and apparatus for switching Fibre Channel Arbitrated Loop Systems is provided between a plurality of Fibre Channel Loop devices. In one aspect of the invention, the system switches based at least in part on arbitrated loop primitives. An exemplary interconnect system may include a first port and a second port, both including port logic to monitor certain arbitrated loop primitives, a connectivity apparatus, a route determination apparatus including a routing table consisting of ALPA addresses and their associated ports, the route determination apparatus coupled to each port and the connectivity apparatus, where the connectivity apparatus creates paths between the ports based on arbitrated loop primitives. In one embodiment, the connectivity apparatus is a crossbar switch. Examples of the arbitrated loop primitives that cause the switch to create paths between ports includes one or more of the following: ARB, OPN and CLS.Type: ApplicationFiled: July 10, 2003Publication date: May 6, 2004Applicant: Vixel CorporationInventors: Bruce Gregory Warren, William Goodwin, Carl Mies, Bruce E. Johnson, Michael L. White, Warren Eng
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Publication number: 20040085995Abstract: The present invention relates in general to a method, apparatus, and article of manufacture for providing high-speed digital communications through a communications channel. In one aspect, the present invention employs a variable rate back channel, incorporated within an existing communication that does not increase or adversely impact the transmission rate of data on the communication channel.Type: ApplicationFiled: September 11, 2003Publication date: May 6, 2004Inventors: James Gorecki, John T. Stonick, Shawn Searles, William S. Check, Robert B. Lefferts
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Publication number: 20040085996Abstract: A modified universal asynchronous receiver transmitter (UART) device is provided with an auxiliary high speed parallel channel using supplementary FIFO buffers for the exchange of data. The auxiliary parallel channel is separate from the normal lower speed serial channel which is retained in unmodified form. The retained serial channel provides full compatibility with and support for the National Semiconductor 16550 standard, while the auxiliary parallel channel allows for rapid transfer of large data blocks, such as is needed for a PCMCIA wireless data card for example. The key advantages of this approach lie both in the data transfer speed and in the reduced amount of development time needed to implement a UART interface for communicating between a host computer and a new subsystem. This is because all the UART functions, except large volume data transfer, can be carried out over the standard serial channel using standard device drivers.Type: ApplicationFiled: October 3, 2003Publication date: May 6, 2004Applicant: Elan Digital Systems LimitedInventor: Peter T. Sleeman
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Publication number: 20040085997Abstract: A P device interworks CE devices connected to the P device using different types of data links. The P device learns the address of a local CE device by monitoring the control messages, such as address resolution messages, originating from the local device. The P device may share the address of a local CE device with another local CE device by initiating a control message or responding to a control message issued by one of the local CE devices. This latter mechanism in effect hides the heterogeneous nature of the network.Type: ApplicationFiled: November 5, 2002Publication date: May 6, 2004Applicant: Tenor Networks, Inc.Inventor: Timothy Mancour
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Publication number: 20040085998Abstract: A method for preventing disconnection of an audio/video stream in a home network includes: a step in which a renderer connected to a server requests A/V streams; a step in which the server judges whether A/V streams can be outputted in response to the request from the renderer; and a step in which the server provides the A/V streams to the renderer sequentially or simultaneously if the A/V stream can be outputted, or outputting a server unavailablness message to the renderer if the server judges that the A/V streams can not be outputted. Without a memory, even though plural renderers are simultaneously or sequentially connected to the server, an abnormal image is prevented from being outputted, so that a service user can be provided with an image without disconnection.Type: ApplicationFiled: September 23, 2003Publication date: May 6, 2004Inventor: Jong-Hyun Yoon
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Method and apparatus for selective segmentation and reassembly of asynchronous transfer mode streams
Publication number: 20040085999Abstract: A method for testing a data network comprises the steps of establishing one or more stream identifiers for reassembly, receiving a cell, and parsing the cell to obtain a current stream identifier. One or more message blocks are established in memory and are related to respective ones of the one or more stream identifiers. The message blocks are for receipt of a portion of the cell if the current stream identifier is one of the one or more stream identifiers that are established for reassembly. The method continues with the step of serially writing a portion of the cell into a one of the message blocks related to the current stream identifier. The method repeats the steps of receiving, parsing and serially writing until said message block is complete.Type: ApplicationFiled: October 31, 2002Publication date: May 6, 2004Inventors: Charles James Burnett, Alan Paul Huff, Scott Blomquist -
Publication number: 20040086000Abstract: A communication protocol over the serial bus allows a peripheral device to control the flow of data between a host computer and the peripheral device so as to maintain synchronization to a periodic reference signal. The protocol involves transferring flow control messages between the peripheral device and the host computer, allowing the peripheral device to control how and when the host computer sends the uncompressed audio and video data. The audio and video data may be sent as separate streams. Using the IEEE-1394 protocol, the flow control messages are sent using an asynchronous protocol, whereas uncompressed video and audio data are sent using an isochronous protocol. Streams of uncompressed video and audio data are transferred from the host computer over a serial bus to the peripheral device, where the peripheral device performs operations on the data such as encoding the data into a standard format, such as DV and MPEG, or generating an analog video signal.Type: ApplicationFiled: November 1, 2002Publication date: May 6, 2004Inventors: Ron Wallace, Harry Der, Martin Corbett, Terrence Fetters
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Publication number: 20040086001Abstract: Using the 1st derivative ultra-narrow Gaussian monocycle pulse passed through a digital shaping multi-band FIR filter may generate a digital ultra-narrow shaped Gaussian monocycle pulse. The spectrum output of the shaped Gaussian monocycle pulse directly meets the FCC's mask restrictions of the emission limits for indoor UWB system. The digital system of generating shaping Gaussian monocycle pulse may be implemented in the off-line operation to save the processing power. The pulse generator in the UWB transceiver has flexibility and scalability of selecting only one shaped pulse out of the data memory banks in which allocate all of the shaped Gaussian monocycle pulses with the different center frequencies. With a shaped pulse generator, an UWB transceiver does not need either a digital shaping transmission filter or an analog shaping transmission filter, with coupling to a D/A converter before or after, during a real-time operation.Type: ApplicationFiled: October 30, 2002Publication date: May 6, 2004Inventors: George J. Miao, Mark A. Clements
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Publication number: 20040086002Abstract: In a data communication circuit, data is multiplexed onto a communication link through multiple multiplexer stages and demultiplexed from the communication link through multiple demultiplexer stages in order that a clock signal applied to each multiplexing circuit need only be precisely distributed to a limited, high frequency portion of the circuit. Each circuit is clocked by a multiplying delayed locked loop bit clock generator. Where the number of parallel bits in the signal between the two stages is greater than two, the higher frequency stage coupled to the communication link is clocked by an N-phase overlapping clock. In the case of a multiplexer, the intermediate frequency signal is enabled in the higher frequency data multiplexer by concurrence of two clock phases.Type: ApplicationFiled: October 28, 2003Publication date: May 6, 2004Applicant: Velio Communications, Inc.Inventors: William J. Dally, John W. Poulton
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Publication number: 20040086003Abstract: Present herein is a multirate transceiver wherein data can be received at a first data rate and transmitted at a second data rate. The transceiver device comprises a first interface for receiving data at one data rate a mapper that can map data from a first rate to the second rate, and a second interface for transmitting the data at the second data rate.Type: ApplicationFiled: January 31, 2003Publication date: May 6, 2004Inventors: Vikram Natarajan, Kang Xiao, Mario Caresosa, Jay Proano, David Chung, Afshin Momtaz, Randy Stolaruk, Xin Wang, Namik Kocaman
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Publication number: 20040086004Abstract: A fibre laser comprises a fibre light guide (3) having an active medium, a laser as pumping source (1) and a first pair of Bragg gratings (6, 8) forming a first resonator (4). The first pair of Bragg gratings (6, 8) resonates the pump laser (1) and there is provided a second pair of Bragg gratings (7, 9) resonating at the output wavelength of the fibre laser.Type: ApplicationFiled: September 10, 2003Publication date: May 6, 2004Inventors: Domenico Bonaccini, Wolfgang Hackenberg
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Publication number: 20040086005Abstract: An ultrashort pulsed laser device includes: a pump laser diode having linear polarization; a solid laser medium oscillating with linear polarization; an optical fiber maintaining a polarization direction; and a saturable absorber mirror. The solid laser medium is disposed between the optical fiber and the saturable absorber mirror. Laser light emitted from the pump laser diode optically is coupled with a first end face of the optical fiber, and laser light emitted from a second end face of the optical fiber pumps the solid laser medium. The first end face of the optical fiber and the saturable absorber mirror constitute a laser resonator. With this configuration, mode lock can be realized stably at a repetition frequency of several hundred MHz.Type: ApplicationFiled: October 22, 2003Publication date: May 6, 2004Applicant: Matsushita Electric Industrial Co., Ltd.Inventors: Yasuo Kitaoka, Kazuhisa Yamamoto
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Publication number: 20040086006Abstract: An optical output stabilizing circuit is disclosed, which comprises a pilot signal generator, a pilot signal amplitude adjusting circuit which adjusts an amplitude of a pilot signal, a laser driving circuit which modulates a driving pulse current of a semiconductor laser by an output signal of the adjusting circuit, and drives the laser by the modulated driving current, a pilot signal detecting circuit which detects a detection voltage corresponding to the amplitude of the pilot signal, a first error amplifier which generates a difference signal by comparing the first detection voltage with a first reference voltage, and which, on the basis of the difference signal, controls the adjusting circuit, and a reference voltage temperature compensating circuit which carries out temperature compensation of the reference voltage of the first error amplifier to decrease fluctuation of an extinction ratio of the output beam of the laser at the high temperature operation time.Type: ApplicationFiled: April 30, 2003Publication date: May 6, 2004Applicant: Kabushiki Kaisha ToshibaInventor: Sadao Tanikoshi
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Publication number: 20040086007Abstract: The present invention provides a method for correcting a shift of an output wavelength of a light source. The output wavelength shift correcting method derives simple equations through experimental processes, predicts a shift degree of the output wavelength with respect to a varied input current using the equations whenever a drive current is reset later, and adjusts a drive temperature according to the predicted shift degree, thus correcting the shift of the output wavelength. The output wavelength shift correcting method is advantageous in that it provides a method of locking an output wavelength of each light source without continuously operating a wavelength locker or a wavelength measuring device, thus reducing the operating cost of the optical communication system.Type: ApplicationFiled: June 3, 2003Publication date: May 6, 2004Inventors: Jyung Chan Lee, Seoung Myong, Je Soo Ko, Seon Mo Kang
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Publication number: 20040086008Abstract: A method of stabilizing output characteristics of an SLD device with respect to ambient temperature is disclosed. The SLD device includes a cooling module for cooling an SLD chip, and a sensor for providing a set point signal corresponding to a set point temperature. The cooling module and the sensor, together with control electronics, form a feedback loop for maintaining the set point temperature within a predetermined range. The method comprises determining a variation of the output characteristics as a function of ambient temperature, and determining a variation of the set point signal as a function of ambient temperature, wherein the variation of the set point signal corresponds to the variation of the output characteristics. The method also includes modifying the feedback loop so as to offset the variation of the set point signal, and thereby stabilize the variation of the output characteristics as a function of ambient temperature.Type: ApplicationFiled: October 30, 2002Publication date: May 6, 2004Inventors: Peter Gregory, Alfred Healy
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Publication number: 20040086009Abstract: Two thin-clad laser diodes are disposed to form a stack-type device that emits two beams. The beams are substantially parallel and in proximity such that they share many fiberoptic systems designed for a single beam. In one embodiment the device functions as a dual-wavelength fiber-pigtailed light source. In another embodiment a feedback mechanism is provided to couple the diodes. Other embodiments include structures and methods for output power enhancement and tunable lasers.Type: ApplicationFiled: October 30, 2002Publication date: May 6, 2004Inventor: Chian Chiu Li
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Publication number: 20040086010Abstract: A laser module comprises a laser diode secured on a semiconductor substrate for emission of a forward laser beam from its front end and a backward laser beam from a point source on its rear end in a horizontal direction. A photodiode, also secured on the substrate, has a light receiving surface extending in the horizontal direction by length L from an edge proximate to the laser diode for receiving a lower half of the backward laser beam, the light receiving surface being lower than the point source by a vertical distance Y, the edge being spaced a horizontal distance Z from the point source of the laser diode, wherein the horizontal distance Z is equal to or greater than (Y/tan &thgr;)−L, where &thgr; is a vertical angle in which the lower half of the backward laser beam radiates from the point source.Type: ApplicationFiled: October 29, 2003Publication date: May 6, 2004Applicant: NEC COMPOUND SEMICONDUCTOR DEVICES, LTD.Inventors: Yusuke Kurihara, Akihiro Ito, Kazushige Mukaihara, Junichi Shimizu
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Publication number: 20040086011Abstract: A planar wafer-level packaging method is provided for a laser and a monitor photo detector. The laser and photo detector are affixed to a planar substrate. The planar substrate provides electrical connections to the components. A lens cap with a microlens is formed and affixed to the substrate with a seal. The lens cap forms a hermetically sealed cavity enclosing the laser and photo detector. The inside surface of the lens cap has a reflective coating with a central opening over the emitting aperture of the laser. The central opening has an anti-reflective coating. Light from the laser is directed and shaped by the lens cap to couple into an external light guide. Residual light from the edge of the laser reflects off the inside surface of the lens cap and is incident upon the photo detector. In an alternate method, the laser may be packaged using flip-chip assembly.Type: ApplicationFiled: October 30, 2002Publication date: May 6, 2004Applicant: Photodigm, Inc.Inventor: Sarvotham M. Bhandarkar
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Publication number: 20040086012Abstract: A coherent light source includes a two-electrode laser diode provided with an active region having an active layer that emits light due to injection of a current, and a phase control region that has a layer that is disposed contiguous with the active layer and in which a change in refractive index is caused by injection of current, and an optical waveguide device in which a DBR (distributed Bragg reflector) region is formed. Laser light that is emitted from the two-electrode laser diode is optically coupled into an optical waveguide of the optical waveguide device, and a portion of the laser light that is emitted from the two-electrode laser diode is reflected by the DBR region and returned to the two-electrode laser diode, thereby locking an oscillation wavelength. Since it is not necessary to form a DBR region on the laser diode, stable wavelength control and modulation control can be achieved at low-cost.Type: ApplicationFiled: October 22, 2003Publication date: May 6, 2004Applicant: Matsushita Electric Industrial Co., LtdInventors: Yasuo Kitaoka, Kazuhisa Yamamoto
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Publication number: 20040086013Abstract: DBR mirrors, and vertical cavity surface emitting lasers that incorporate such mirrors, comprised of stacked, multiple levels of different materials having different etching rates for a selected etchant and etching method. Such DBRs are fabricated by etching an upper level(s) down to a lower level(s) to form a pillar or trenched structure, beneficially having an aperture, that has predetermined optical characteristics. When part of a vertical cavity surface emitting laser, a lower level can include an ion-implanted region that optionally extends into an active region and into a bottom DBR.Type: ApplicationFiled: October 30, 2002Publication date: May 6, 2004Inventor: Jin K. Kim
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Publication number: 20040086014Abstract: A semiconductor laser having an emitting wavelength is disclosed. The semiconductor laser having an emitting wavelength includes plural quantum well groups respectively having quantized energy levels wherein the quantized energy levels are mutually different. The emitting wavelength of the semiconductor laser is set in one of the plural quantum well groups having a relatively high quantized energy level for reducing a temperature effect on the semiconductor laser.Type: ApplicationFiled: April 17, 2003Publication date: May 6, 2004Applicant: ARIMA OPTOELECTRONICS CORP.Inventor: Ching-Fuh Lin
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Publication number: 20040086015Abstract: An optical waveguide is provided on an n-type buffer layer. The optical waveguide is formed into a mesa form. A high resistance layer narrows a drive current path through the optical waveguide. Two trenches are formed such that their bottoms are in contact with the high resistance layer. This can effectively narrow the drive current path in the semiconductor laser device part.Type: ApplicationFiled: October 9, 2003Publication date: May 6, 2004Inventors: Takahiko Kawahara, Michio Murata
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Publication number: 20040086016Abstract: Long-wavelength VCSELs having top DBR mirrors with multiple levels. The individual levels of the DBR are comprised of different materials. The top DBR mirror level(s) forms a pillar structure and/or are defined by trenches. Top contacts are formed on the top DBR mirror below that mirror's top level. An aperture is formed in one of the DBR layers. An ion implanted region is formed in the top DBR and may extend into the active region and into part of a bottom DBR. The top DBRs are beneficially fabricated by etching parts of upper level(s) down to the lower level(s).Type: ApplicationFiled: October 30, 2002Publication date: May 6, 2004Inventor: Jin K. Kim
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Publication number: 20040086017Abstract: In a semiconductor laser device having a GRIN-SCH-MQW structure, attention is paid to correlation among a lasing wavelength, a refractive index difference between an equivalent refractive index in a region including an active layer and an equivalent refractive index in a region including current blocking layers, and a composition of a barrier layer having a quantum well structure. By finding out an optimum combination of these three parameters, a width of the active layer is made wider than a conventional width, thus preventing occurrence of a kink due to horizontal transverse mode in the active layer.Type: ApplicationFiled: February 19, 2003Publication date: May 6, 2004Applicant: THE FURUKAWA ELECTRIC CO., LTD.Inventors: Junji Yoshida, Naoki Tsukiji
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Publication number: 20040086018Abstract: External-cavity optically-pumped semiconductor lasers (OPS-lasers) including an OPS-structure having a mirror-structure surmounted by a surface-emitting, semiconductor multilayer (periodic) gain-structure are disclosed. The gain-structure is pumped by light from diode-lasers. The OPS-lasers can provide fundamental laser output-power of about two Watts (2.0 W) or greater. Intracavity frequency-converted arrangements of the OPS-lasers can provide harmonic laser output-power of about one-hundred milliwatts (100 mW) or greater, even at wavelengths in the ultraviolet region of the electromagnetic spectrum. These high output powers can be provided even in single axial-mode operation.Type: ApplicationFiled: October 28, 2003Publication date: May 6, 2004Inventors: Andrea Caprara, Juan L. Chilla, Luis A. Spinelli
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Publication number: 20040086019Abstract: There is provided a millimeter wave band frequency optical oscillator predicted to be used as a millimeter wave oscillating frequency signal source in a base station of a millimeter wave wireless transmission system. The optical oscillator has a double resonator structure in which a pair of wavelength tunable fiber grating mirrors are inserted into a unilateral fiber-ring laser resonator in order to internally and additionally form a linear laser resonator. The double resonator structure composed of the two stable laser resonators can oscillate laser of two modes. Due to a beat phenomenon occurring between the two modes, received laser is modulated to an ultra-speed frequency of 60 GHz or greater. A variation in the gain within a resonator is induced by a polarization controller using the dependency of laser modes upon polarization. A modulation frequency is consecutively changed from 60 GHz to 80 GHz by controlling the wavelength of light reflected by the fiber grating mirrors.Type: ApplicationFiled: March 3, 2003Publication date: May 6, 2004Inventors: Ho-Young Kim, Eun-Soo Nam, Kyoung-Ik Cho
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Publication number: 20040086020Abstract: A method and device for performing diagnostic analyses on a liquid system is capable of detecting physical and/or chemical changes within the system by noting temperature changes, typically increases, within the device. These temperature changes can be relayed to alert an operator of the change in physical and/or chemical properties within the system so that remedial action can be taken.Type: ApplicationFiled: October 27, 2003Publication date: May 6, 2004Inventor: Marlow C. Jordahl
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Publication number: 20040086021Abstract: A solar receiver system for utilizing solar energy to produce electrical power and to generate a temperature profile of a plurality of receiver tubes utilized in the system. The solar receiver system includes a solar receiver having a plurality of receiver panels including the plurality of receiver tubes through which a coolant flows. Additionally, the solar receiver system includes a plurality of IR cameras adapted to view at least a portion of a surface area of the solar receiver. Each IR camera is adapted to have a field of view including a different specified region of the surface area of the solar receiver. Furthermore, the solar receiver system includes a master control system adapted to receive an IR image from each IR camera, wherein each IR image depicts surface area temperatures and variances over the region of the solar receiver viewed by each IR camera. The master control system generates a temperature profile of the surface area of the solar receiver utilizing the IR images.Type: ApplicationFiled: November 1, 2002Publication date: May 6, 2004Inventor: Robert Zachary Litwin
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Publication number: 20040086022Abstract: The invention relates to an infrared thermometer, especially an ear thermometer for measuring temperature, comprising an infrared sensor, a measuring tip which can be heated by a heating element, an actuating device which can be operated by a user, a control device and a display device. The invention also relates to a method for measuring temperature, especially by means of a radiation thermometer having a heatable measuring tip. Said control device switches off the heating element after the user has actuated an actuating device. After a certain amount of time, a plurality of temperature measurements are successively carried out, and the temperature to be displayed is determined from said measured temperatures or an error message is generated. At the latest, after a maximum measuring time has elapsed or after a maximum number of temperatures have been measured, the temperature to be displayed or an error message is displayed on the display device.Type: ApplicationFiled: January 5, 2004Publication date: May 6, 2004Inventors: Bernhard Kraus, Alexander Klos
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Publication number: 20040086023Abstract: The invention provides a control strategy and a control system to control a gas sensor to a target operating temperature. It relies upon both feedback and model-based feedforward control systems to achieve and then maintain the sensor at the target operating temperature. The mechanization includes a gas sensor with a heating element in a feedstream. The control strategy employs a control system for the heating element that is based upon the target operating temperature, the temperature of the heating element, and an effect of the feedstream and mounting structure on the temperature of the sensor. The control strategy enables the control system to optimize the heating of a sensor during warm-up and steady state operations.Type: ApplicationFiled: October 31, 2002Publication date: May 6, 2004Inventors: James Craig Smith, Wayne Richard Moore, Matthew G. Foster
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Publication number: 20040086024Abstract: Oxidation of turbine buckets may cause unexpected and expensive turbine failures. Turbine bucket oxidation condition may be estimated to predict remaining useful bucket life during operation of a turbine by processing time-varying temperature distributions measured with a pyrometer of at least one rotating turbine bucket.Type: ApplicationFiled: November 6, 2002Publication date: May 6, 2004Inventor: Sukhwan Choi