Patents Issued in August 31, 2004
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Patent number: 6785308Abstract: A system and method for spectral conditioning an optical signal. An optical filter has an input for receiving an emitted optical signal and an output providing a filtered optical signal. The filter has a corresponding filter profile which includes a high wavelength skirt at an upper wavelength region of the filter profile. A laser is optically coupled to the optical filter input and emits the emitted optical signal. The laser is controllable to emit the optical signal at a wavelength proximate to the optical filter high wavelength skirt.Type: GrantFiled: March 28, 2002Date of Patent: August 31, 2004Assignee: Nortel Networks LimitedInventors: Peter J. Dyer, Tom M. Luk, Jean-Philippe Martel
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Patent number: 6785309Abstract: A method for frequency and mode stabilisation of a tuneable laser that has at least three sections, such as a Bragg laser or GCSR laser, where measurable magnitudes are measured and the laser has been characterised with respect to a number of operation points, and where the values of the measurable magnitudes are stored in a microprocessor or corresponding device. The invention is characterised in that the values of one or more of the measurable magnitudes (E) are caused to be non-extreme values; in that the measurable magnitudes include back power in addition to front power and frequency; and in that control currents (I1, I2, I3; I1, I2, I3, I4) for the gain section (P1), the phase section (N2; N3) and the reflector section (N3; N4) respectively of said laser, and when applicable also for the coupler section (N2) of said laser, are caused to be controlled on the basis of the measured values of said measurable magnitudes while keeping both the front power and back power constant.Type: GrantFiled: November 18, 2002Date of Patent: August 31, 2004Assignee: ADC Telecommunicatiions, Inc.Inventor: Jan-Olof Wesström
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Patent number: 6785310Abstract: To improve a diode laser device comprising at least one laser diode, a power supply for the laser diode, a cooling device including a heat sink with the laser diode disposed thereon, and a coolant supply allowing a coolant to flow through the heat sink, so that simple monitoring of its operation is possible without interfering with use of the diode laser device, it is proposed that an operation monitoring device be provided, and that the operation monitoring device detect a quantity representing the electric current flowing through the laser diode and a quantity representing the temperature of the coolant exiting from the heat sink and determine from these an operational quantity representing operation of the diode laser device.Type: GrantFiled: October 9, 2002Date of Patent: August 31, 2004Assignee: Trumpf Laser GmbH + Co. KGInventors: Rudolf Huber, Martin Huonker, Thomas Konrad Notheis, Klaus Wallmeroth
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Patent number: 6785311Abstract: An optical semiconductor device comprising: an active region; and a p-doped cladding region disposed on one side of the active region; wherein an electron-reflecting barrier is provided on the p-side of the active region for reflecting both &Ggr;-electrons and X-electrons, the electron-reflecting barrier providing a greater potential barrier to &Ggr;-electrons than the p-doped cladding region.Type: GrantFiled: August 27, 2001Date of Patent: August 31, 2004Assignee: Sharp Kabushiki KaishaInventor: Stephen Peter Najda
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Patent number: 6785312Abstract: A digital optical communication method transmits an optical signal over a long distance with a reduced power penalty. The method has the step of shaping the waveform of the optical signal to be transmitted through the optical fiber to increase the frequency thereof before the waveform is stabilized when the optical signal starts increasing in level at the time the optical signal is applied to the optical fiber.Type: GrantFiled: August 14, 2001Date of Patent: August 31, 2004Assignee: NEC CorporationInventor: Kenji Sato
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Patent number: 6785313Abstract: A distributed Bragg reflector laser is fabricated wherein material defects are produced in the laser's tuning waveguide region. The defects may be created by introducing impurities into the region. The defects increase the non-radiative recombination rate of injected carriers, thereby decreasing FM efficiency and improving RF performance. Injected carrier electrons are substantially separated from injected carrier holes to reduce bimolecular and Auger recombination rates, thus improving tuning range.Type: GrantFiled: January 16, 2003Date of Patent: August 31, 2004Assignee: Lucent Technologies Inc.Inventor: Kishmore K. Kamath
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Patent number: 6785314Abstract: There is provided an electric discharge gas laser comprising a housing, a rotating fan, a bearing device and a control. The housing contains a laser gas. The rotating fan is provided in the housing to circulate the gas in the housing. The bearing device magnetically supports a rotating shaft. The bearing device is provided with a sensor device comprising a sensor and a signal processor. The sensor senses the position of the rotating shaft to generate signals indicating the position of the rotating shaft. The signal processor receives and processes the signals delivered from the sensor to output processed signals. The control is separated from the bearing device and is functionally associated with the bearing device to receive the processed signal from the sensor device for controlling the bearing device on the basis of the processed signals.Type: GrantFiled: June 8, 2001Date of Patent: August 31, 2004Assignee: Ebara CorporationInventors: Atushi Ooyama, Shinichi Sekiguchi, Hiroyuki Shinozaki, Toshimitsu Barada, Toshiharu Nakazawa
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Patent number: 6785315Abstract: A laser weapon system using a high energy deuterium fluoride (DF) or hydrogen fluoride (HF) laser, for which all necessary reactants and other materials are carried on an easily movable vehicle. Reactant gases are stored mixed with a diluent gas, such as helium, for ease of handling and to provide nearly ideal gas behavior. Cooling water for the laser is also employed in a high pressure steam generator that uses diesel fuel and oxygen to produce heat. Apart from a fluorine generator, the system uses only four storage tanks for reactant gases.Type: GrantFiled: September 24, 2001Date of Patent: August 31, 2004Assignee: Northrop Grumman CorporationInventors: Dale L. Hook, Josef Shwartz, Jeffery L. Sollee, Ethan W. Brigham, Milton H. Gran
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Patent number: 6785316Abstract: A final stage capacitance of a pulse compression circuit for an excimer or molecular fluorine lithography laser system is provided by a set of peaking capacitors connected through a first inductance to the electrodes and a set of sustaining capacitors connected to the electrodes through a second inductance substantially greater than the first inductance. Current pulses through the discharge are temporally extended relative to current pulses of a system having its final stage capacitance provided only by a set of peaking capacitors connected to the electrodes via the first inductance. An amplified spontaneous emission (ASE) level in the laser pulses is reduced thereby enhancing their spectral purity.Type: GrantFiled: August 17, 2000Date of Patent: August 31, 2004Assignee: Lambda Physik AGInventors: Igor Bragin, Vadim Berger, Uwe Stamm
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Patent number: 6785317Abstract: The present invention relates to vertical-cavity surface-emitting lasers (VCSELs), and more particularly to a method and apparatus for controlling and stabilization of polarization in such devices. The method for stabilizing the polarization of light generated by a VCSEL assembly comprising a light generation region of a VCSEL, the VCSEL being mechanically coupled to a mounting substrate, comprises the steps of: mechanically coupling the mounting substrate to a second substrate which is coextensive or larger in area than the mounting substrate, and applying uniaxial strain to the light generation region of the VCSEL by means of external strain applied to the mounting substrate by the second substrate or by means attached to the second substrate.Type: GrantFiled: September 10, 2002Date of Patent: August 31, 2004Assignee: Vrije Universiteit BrusselsInventors: Krassimir Panajotov, Hugo Thienpont, Irina Veretennicoff
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Patent number: 6785318Abstract: Described is a semiconductor laser for generating an optical beam having a stable polarization mode. The laser includes a semiconductor structure having an active layer and a stressor disposed on the surface of the semiconductor structure. Birefringence and gain anisotropy are induced in the semiconductor structure in response to the stress applied by the stressor. The active layer includes one or more quantum wells fabricated to generate an interfacial strain and a desired gain anisotropy. By fabricating the active layer away from the stressor, the gain anisotropy induced by the stressor is substantially reduced. Consequently, the gain anisotropy from the interfacial stress is greater than the gain anisotropy induced by the stressor. The resulting semiconductor structure has a maximum refractive index direction that is parallel to the direction of maximum gain, thus enabling a stable polarization mode for the laser.Type: GrantFiled: November 14, 2002Date of Patent: August 31, 2004Assignee: Nortel Networks LimitedInventors: Yasuhiro Matsui, Daryoosh Vakhshoori, Peidong Wang
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Patent number: 6785319Abstract: A narrow band ultraviolet laser device which can restrict a change in temperature gradient at light transmitting sections and maintain laser light at a high grade. To this end, the ultraviolet laser device includes light shielding elements (37A to 37C) having light transmitting sections (47A to 47C) each constituted by an opening for transmitting laser light (11), and light shielding sections (49A to 49C) that surround the light transmitting sections (47A to 47C), remove an undesired laser light (11A) from an optical path and shape the laser light (11) into a predetermined form, wherein heating means (45) for heating the light transmitting sections (47A to 47C) are provided in the vicinity of the light shielding elements (37A to 37C).Type: GrantFiled: February 7, 2002Date of Patent: August 31, 2004Assignee: Komatsu Ltd.Inventors: Tatsuya Ariga, Takahito Kumazaki, Jun Akita, Noritoshi Itoh
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Patent number: 6785320Abstract: A vertical cavity surface emitting laser (VCSEL) comprising a one dimensional grating structure configured to act as a waveguide, preferably located at an end surface of the VCSEL, for selectively reflecting more of a first polarisation of light back into the cavity of the VCSEL than a second orthogonal polarisation of light. Preferably the VCSEL comprises an upper Bragg mirror, a gain region, and a lower Bragg mirror, and the one dimensional grating structure is located on a top layer of the upper Bragg mirror and the top layer of the upper Bragg mirror has a thickness such that the reflected light of one polarisation constructively interferes with light of said one polarisation which is reflected by the upper Bragg mirror. The VCSEL will then lase at the polarisation which is more predominantly reflected by the grating structure.Type: GrantFiled: February 12, 2002Date of Patent: August 31, 2004Assignee: QinetiQ LimitedInventors: Richard M Amos, Meirion F Lewis, Rebecca A Wilson
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Patent number: 6785321Abstract: A threshold tracking loop (TTL) (400) for detecting the time of arrival of a spread spectrum wireless communication signal includes a pseudo-noise (PN) generator (440) for generating a receive PN code for use in spread spectrum decoding and a series of time delay units (401-408) for adjusting a phase offset of the PN code. A first PN despreader (423) is coupled to the time delay units and PN generator for despreading an early pilot signal (413). A second despreader (425) is coupled to the time delay units and PN generator for despreading a late pilot signal (415). A first comparison circuit (443) is coupled to the first PN despreader for comparing a signal value of the early pilot signal with a preselected threshold value (322) and for advancing the PN code phase offset if the early signal value is greater than the threshold value.Type: GrantFiled: October 31, 2000Date of Patent: August 31, 2004Assignee: Motorola, Inc.Inventors: Roy Yang, Jiangnan Jason Chen
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Patent number: 6785322Abstract: A Node-B/base station receiver comprises at least one antenna for receiving signals. Each finger of a pool of reconfigurable Rake fingers recovers a multipath component of a user and is assigned a code of the user, a code phase of the multipath component and an antenna of the at least one antenna. An antenna/Rake finger pool interface provides each finger of the Rake pool an output of the antenna assigned to that Rake finger. A combiner combines the recovered multipath components for a user to produce data of the user.Type: GrantFiled: December 27, 2002Date of Patent: August 31, 2004Assignee: InterDigital Technology CorporationInventors: John David Kaewell, Jr., Timothy Berghuis, Jan Meyer, Peter Bohnhoff, Alexander Reznik, Edward Hepler, Michael Koch, William C. Hackett, David S. Bass, Clyde N. Robbins
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Patent number: 6785323Abstract: A technique for encoding a signal used in a digital communication system in which individual traffic channel data rates may be adapted to specific channel conditions. In particular, a forward error correction coding rate is adapted for individual channels while at the same time maintaining a fixed block size independent of the FEC coding rate. This allows the system data rate to adapt to the channel conditions experienced by a specific user. Thus, users experiencing good communication conditions with low multipath distortion may be allocated higher capacity, whereas users with significant multipath distortion may make use of lower rate (higher levels of coding) error codes to maintain high quality. Messages are sent from a transmitter to a receiver to inform the receiver of the coding rate implemented at any given point in time.Type: GrantFiled: November 22, 1999Date of Patent: August 31, 2004Assignee: IPR Licensing, inc.Inventor: James A. Proctor, Jr.
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Patent number: 6785324Abstract: A full-duplex radio transceiver includes a transmitter and a receiver. A duplexer is connected to an output of the transmitter and an input of the receiver. The receiver includes a low noise amplifier having a nonlinear portion capable of generating undesired cross-modulation signals based upon a portion of the transmit signal coupled thereto from the duplexer and a signal from another adjacent transmitter. A bandpass filter is connected to an output of the low noise amplifier, and at least one downconverter stage is connected to an output of the bandpass filter. A reactive termination circuit is connected between the low noise amplifier and the bandpass filter for changing an impedance presented to the output of the low noise amplifier with respect to signals from the colocated transmitter to thereby reduce undesired cross-modulation signals.Type: GrantFiled: October 26, 1999Date of Patent: August 31, 2004Assignee: Intersil CorporationInventors: Richard Douglas Schultz, Raphael Leite B. Matarazzo
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Patent number: 6785325Abstract: A DSL splitter providing test access to an interconnected subscriber loop and method are disclosed. The DSL splitter in a first test mode, provides access to allow testing of an interconnected subscriber loop by way of a DSL input. A disconnect in series with an associated low pass filter (LPF) disconnects POTS input. Such a splitter may similarly provide access to allow testing of the subscriber loop by way of the POTS input in a second test mode. In this second test mode, a by-pass by-passes the LPF, and a disconnect may disconnect an associated high pass filter (HPF) and DSL input. Preferably, the splitter only assumes its test modes after receipt of authorization from the other provider. The splitter may be controllable by way of a control circuit having an access port used to receive commands to have the splitter assume its normal, or first or second test mode. The splitter may assume its normal operating mode from a test mode, after expiry of a timeout timer.Type: GrantFiled: June 7, 2000Date of Patent: August 31, 2004Assignee: Nortel Networks LimitedInventors: Gin Liu, Anthony Peck, Alfred Haw
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Patent number: 6785326Abstract: The present invention relates generally to impairment detection and compensation in a communications network. One embodiment includes a method for generating an adaptive Digital Impairment Learning (DIL) sequence for use in a training mode which assists in resolving digital loss ambiguities affecting the mapping of analog levels to digital levels in a communications network. The method includes identifying a feature octet for a pair of the digital loss ambiguities, determining a number of transmit copies of the feature octet based at least in part upon a noise variance, and modifying a standard DIL sequence with the number of transmit copies of the feature octet to produce the adaptive DIL sequence for use in the training mode. Alternate embodiments relate to an apparatus for generating an adaptive DIL sequence for use in a training mode and an apparatus and method for compensating for digital losses in a communications network.Type: GrantFiled: August 7, 2000Date of Patent: August 31, 2004Assignee: Freescale Semiconductor, Inc.Inventor: Lijun Daniel Tan
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Patent number: 6785327Abstract: Multiported register files used for storing coefficients in adaptive FIR are improved upon by implementing a split memory architecture that has the ability to separately control the least significant bits and the most significant bits of coefficient values that are stored in the filter. When the filter is operated to use so-called “burst mode” updating, the updating circuitry of the filter can be disabled and only the most significant bits of the coefficients are read out from the multiported register file while the least significant bits remain unchanged. This conserves power without sacrificing precision, since only certain ones of the bits of the coefficients are used in the multiplication of the sample.Type: GrantFiled: December 23, 1997Date of Patent: August 31, 2004Assignee: Agere Systems, Inc.Inventors: Patrik Larsson, Christopher John Nicol
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Patent number: 6785328Abstract: A multiple carrier communication system includes a primary impulse shortening filter that receives an output signal of an analog to digital converter and accepts coefficients. A secondary impulse shortening filter receives the output signal of the analog to digital converter, outputs an output signal, and passes coefficients to the primary impulse shortening filter. A reference signal generator outputs a reference signal. A comparator compares the output signal and the reference signal and outputs a resulting error signal. An adaptive processor computes coefficients for the secondary impulse shortening filter based on the error signal.Type: GrantFiled: December 17, 2002Date of Patent: August 31, 2004Assignee: Tellabs Operations, Inc.Inventors: Gopal Harikumar, Daniel J. Marchok, Kenneth J. Rudofski
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Patent number: 6785329Abstract: Automatic video object extraction that defines substantially precise objects is disclosed. In one embodiment, color segmentation and motion segmentation are performed on a source video. The color segmentation segments the video by substantially uniform color regions thereof. The motion segmentation segments the video by moving regions thereof. The color regions and the moving regions are then combined to define the video objects. In varying embodiments, pre-processing and post-processing is performed to further clean the source video and the video objects defined, respectively.Type: GrantFiled: December 21, 1999Date of Patent: August 31, 2004Assignee: Microsoft CorporationInventors: Jinhui Pan, Shipeng Li, Ya-Qin Zhang
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Patent number: 6785330Abstract: A method for encoding and transmitting a video signal which includes creating a low bit rate video transport stream from the video signal. Excluded bits derived from the video signal which were not included in the base transport stream are included in one or more separate enhancement transport streams. The base transport stream and each enhancement transport stream is then separately transmitted over at least one communications network.Type: GrantFiled: August 18, 2000Date of Patent: August 31, 2004Assignee: Ghildra Holdings, Inc.Inventors: Matthew J. Whealton, Kwok L. Li, Jonathan M. Katz
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Patent number: 6785331Abstract: Video data predictive encoding methods using the two kinds of prediction modes, the global and local motion compensation modes, are provided, by which unnecessary MCSEL is reduced as much as possible, and the data compression efficiency is improved. In the encoder, after a code word MCBPC indicating the macroblock type and presence/absence of the DCT coefficient of each of two blocks for sending color-difference signals, a code word MCSEL indicating which motion-compensating mode, global or local, was adopted for the prediction of the current macroblock is output if the macroblock was not intraframe-encoded.Type: GrantFiled: July 28, 1999Date of Patent: August 31, 2004Assignee: Nippon Telegraph and Telephone CorporationInventors: Hirohisa Jozawa, Atsushi Shimizu, Kazuto Kamikura, Hiroshi Watanabe
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Patent number: 6785332Abstract: A method for marking a compressed digital video signal by embedding a digital signature in the compressed video signal, the signal representing a series of at least two video images, each image being divided into a plurality of regions, the signal including movement vectors representing the movement of the regions between the first and the second image, characterised in that it consists in modifying at least one of the coefficients X or Y of at least one of the movement vectors.Type: GrantFiled: January 18, 2000Date of Patent: August 31, 2004Assignee: Ecole Polytechnique Federale de LausanneInventors: Martin Kutter, Frédéric Jordan, Touradj Ebrahimi
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Patent number: 6785333Abstract: A motion vector coding method is provided. The motion vector coding method includes the steps of (a) performing an affine motion estimation to obtain affine motion parameters, (b) converting the affine motion parameters to a predetermined number of translational motion vectors, and (c) coding the difference between the converted translational motion vectors of a current block and the converted translational motion vectors of a previous block. The method allows for low bit generation while maintaining motion estimation performance available from affine motion estimation.Type: GrantFiled: May 24, 2001Date of Patent: August 31, 2004Assignee: Samsung Electronics Co., Ltd.Inventor: Kook-yeol Yoo
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Patent number: 6785334Abstract: In a Fine Granular Video encoding system, a method for determining the number of transmission bits of SNR encoded and temporally encoded video data within a frame to balance image quality and object motion is presented. In accordance with the principles of the invention, a number of transmission bits at a known bit-rate for a quality enhanced video frame and a temporal enhanced video frame is determined to balance image quality and object motion smoothness. In one aspect of the invention, the number of bits transmitted in each frame is determined by comparing a ratio of a measure of video encoded information within the quality enhanced video frame and a measure of video encode information within the quality enhanced video frame and the temporally enhanced video frame to a known threshold level. The number of transmission bits in each enhancement layer is then determined using a first method when the ratio is above a known threshold and using a second method otherwise.Type: GrantFiled: August 15, 2001Date of Patent: August 31, 2004Assignee: Koninklijke Philips Electronics N.V.Inventors: Mihaela van der Schaar, Hayder Radha
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Patent number: 6785335Abstract: A system and corresponding method for adjusting the brightness and color of MPEG encoded video images. A digital versatile disk player capable of decoding a previously encoded MPEG video signal and adjusting the brightness and color of the entire previously encoded MPEG video signal based on a subset of information contained in the encoded input signal. The brightness and color adjustments are performed while the encoded MPEG video signal is in the frequency (dct) domain before motion compensation is performed. The digital versatile disk player also determines whether the particular block to be decoded is of a predetermined type and decodes such block accordingly.Type: GrantFiled: November 9, 2000Date of Patent: August 31, 2004Assignee: InterVideo Inc.Inventor: Shahab Layeghi
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Patent number: 6785336Abstract: In accordance with a specific aspect of the present invention, a compressed video stream, such as an MPEG-2 video stream, is received by a transport demultiplexor, synchronized, parsed into separate packet types, and written to buffer locations external the demultiplexor. Adaptation field is handled by a separate parser. In addition, primary elementary stream data can be handled by separate primary elementary stream parsers based upon the packet identifier of the primary elementary stream. Video packets can be parsed based upon stream identifier values. Specific packets of data are stored in one or more system memory or video memory buffers by an output controller based upon allocation table information. Private data associated with specific elementary streams or packet adaptation fields are repacketized, and written to an output buffer location. In specific implementations, the hardware associated with the system is used to acquire the data stream without any knowledge of the specific protocol of the stream.Type: GrantFiled: January 24, 2000Date of Patent: August 31, 2004Assignee: ATI Technologies, Inc.Inventors: Branko Kovacevic, Kevork Kechichian
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Patent number: 6785337Abstract: In an MPEG picture processing apparatus, a for-reconstructed-picture data transfer for picture data relating to the decoding performed in a video decoder is performed between the video decoder and an SDRAM, and a second type data transfer for each second type of data is performed between a local buffer and the SDRAM. The for-reconstructed-picture data transfer is preferentially performed at a fixed data transfer quantity in an optimum transfer time-period of the picture data. To preferably perform the for-reconstructed-picture data transfer, a possible data transfer quantity of each second type of data is limited to a minimum value in the optimum transfer time-period of the picture data, and the limitation for the possible data transfer quantity is weak in a non-limited time-period other than the optimum transfer time-period of the picture data.Type: GrantFiled: December 18, 2000Date of Patent: August 31, 2004Assignee: Renesas Technology Corp.Inventors: Ryohei Okawahara, Akihiko Takabatake
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Patent number: 6785338Abstract: Compression-related information is used to constrain the selection and control of video imagery and content used to produce one or more uncompressed video streams for subsequent compression processing. Rather than taking an uncompressed video stream “as is” for compression processing, characteristics of compression processing are taken into consideration during the video production stage when the uncompressed video stream is generated. Different types of constraints include “intra-frame” constraints that constrain video content within a frame of a video stream, “inter-frame” constraints that constrain video content from frame to frame within a video stream, and “inter-stream” constraints that constrain video content across different video streams. Two or more different constraints and two or more different types of constraints may be applied simultaneously. The compression-related information may be “static” (e.g.Type: GrantFiled: January 18, 2000Date of Patent: August 31, 2004Assignee: Sarnoff CorporationInventors: Glenn Arthur Reitmeier, Robert Norman Hurst, Jr., Terrence Raymond Smith
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Patent number: 6785339Abstract: An apparatus (200) checks voice quality when in a vocoder bypass mode. If the voice quality level is beyond an acceptable range, the apparatus (200) ends the vocoder bypass mode and returns to tandem vocoding. For example, a vocoder bypass controller (206) includes a speech quality detector (225) that determines the speech quality level of speech information based on at least one of detected volume level, echo level and noise level of the speech information. The vocoder bypass controller (206) with the speech quality detector (225) outputs a speech quality-based vocoder bypass control signal (236) to selectively activate or deactivate a vocoder bypass operation in response to the speech quality-based vocoder bypass control signal (236). In another embodiment, a network element for communicating speech packets includes an incoming decoder (512) and a speech quality detector (514) operative to determine the speech quality level of incoming speech packets.Type: GrantFiled: October 31, 2000Date of Patent: August 31, 2004Assignee: Motorola, Inc.Inventors: Mansour Tahernezhaadi, J. Douglas Brophy, Lee M. Proctor, Michael J. Kirk
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Patent number: 6785340Abstract: A central office line unit (COLU) for a pulse code modulation (PCM) upstream and downstream system in a universal digital loop carrier (UDLC) includes a hybrid circuit for transmitting/receiving an analog signal to/from a switch. An analog-to-digital converter is provided for receiving the analog signal from the hybrid circuit and converting the analog signal to a converted digital signal. A digital transmission circuit transmits/receives a digital signal to/from a remote terminal. A quantizer is provided for evaluating and processing the converted digital signal so that only valid states of the converted digital signal are transmitted to the digital transmission circuit for transmission to the remote terminal. A receiver is used for receiving the digital signal from the digital transmission circuit and for evaluating and processing the digital signal so that only valid states of the digital signal are outputted from the receiver.Type: GrantFiled: May 25, 2000Date of Patent: August 31, 2004Assignee: ADC DSL Systems, Inc.Inventors: John F. Stockman, David M. Motley, Richard A. Kolbush, Robert Kroninger
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Patent number: 6785341Abstract: Techniques to “successively” process received signals at a receiver unit in a MIMO system to recover transmitted data, and to “adaptively” process data at a transmitter unit based on channel state information available for the MIMO channel. A successive cancellation receiver processing technique is used to process the received signals and performs a number of iterations to provide decoded data streams. For each iteration, input (e.g., received) signals for the iteration are processed to provide one or more symbol streams. One of the symbol streams is selected and processed to provide a decoded data stream. The interference due to the decoded data stream is approximately removed (i.e., canceled) from the input signals provided to the next iteration. The channel characteristics are estimated and reported back to the transmitter system and used to adjust (i.e., adapt) the processing (e.g., coding, modulation, and so on) of data prior to transmission.Type: GrantFiled: May 11, 2001Date of Patent: August 31, 2004Assignee: Qualcomm IncorporatedInventors: Jay R. Walton, Mark Wallace, John W. Ketchum, Steven J. Howard
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Patent number: 6785342Abstract: Method for predistortion compensation for nonlinear distortion produced by the non-linear power amplifier of the QAM signal at the transmitter side of the direct digital communication channel. The out-of-band signal power is monitored by the existent receiver at the receive side of the direct propagation channel. The nonlinear distortion compensation signal is generated at the receiver/demodulator side of the direct propagation channel and transmitted across the direct propagation channel to an input of a pre-distortion block at the transmitter/modulator side of the direct propagation channel. The nonlinear distortion compensation signal is used to adjust the set of parameters of the pre-distortion block in order to minimize the out-of-band power produced by the non-linear amplifier (NLA).Type: GrantFiled: November 6, 2000Date of Patent: August 31, 2004Assignee: Wideband Semiconductors, Inc.Inventors: David Bruce Isaksen, Byron Esten Danzer
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Patent number: 6785343Abstract: A normalizer (70) truncates a variable plurality of numbers of least significant bits of input I and Q words representing an original phase angle in rectangular coordinates. A read only memory (90′) generates a phase signal representing a resultant phase angle range in polar coordinates that includes the original phase angle.Type: GrantFiled: October 20, 2000Date of Patent: August 31, 2004Assignee: Northrop Grumman CorporationInventor: Hanna S. Hsu
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Patent number: 6785344Abstract: The present invention includes a system that determines a threshold to distinguish between binary signals. The system includes a bit wise threshold determination device coupled to receive an input signal and that delays the input signal, averages the input signal and the delayed input signal, and outputs the average to an output node. The average represents a threshold value. This system can be used in any system that must determine a threshold between binary values.Type: GrantFiled: July 12, 2000Date of Patent: August 31, 2004Assignee: Terawave Communications, Inc.Inventors: Jing Wen Jiang, Robert J. Deri
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Patent number: 6785345Abstract: A frequency dither technique is used for reducing spurs due to phase increment errors in a direct digital synthesizer output sinusoid. The spurs for a desired output frequency are calculated and, if the spurs fall within a phase locked loop bandwidth, a pair of phase increment values are used representing a pair of frequencies that average to the desired output frequency and the spurs of which fall outside the phase locked loop bandwidth.Type: GrantFiled: January 18, 2001Date of Patent: August 31, 2004Assignee: Tektronix, Inc.Inventor: Stephen F. Blazo
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Patent number: 6785346Abstract: A digital demodulator which coherently demodulates a low-IF or zero-IF complex signal using a complex-valued phase-locked loop (CPPL). The CPPL includes a numerical controlled oscillator, four multipliers and two combiners to provide independent phase/frequency and amplitude outputs. The CPLL exhibits in first order PLL dynamics without a loop filter in the feedback loop to the NCO. However a filter with one or more poles may be included in the feedback circuit to exhibit 2nd or higher order PLL dynamics. The CPLL allows coherent demodulation of extremely low FM modulation indexes whereby the incoming frequency drift may be larger than the frequency deviation. It can also be used to coherently demodulate signals which have combined amplitude and phase characteristics.Type: GrantFiled: September 29, 2000Date of Patent: August 31, 2004Assignee: Skyworks Solutions, Inc.Inventors: Neil Birkett, Norm Filiol, Thomas Riley
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Patent number: 6785347Abstract: Disclosed is a method and apparatus for receiving FSK signals using estimation theory. A received signal is filtered to obtain energy estimates for a first frequency corresponding to a binary “0” and a second frequency corresponding to a binary “1”. The energy estimates are subtracted to obtain a difference value and an odd number of samples of a series of difference values is smooth filtered in order to produce a series of average values. A sliding window is applied to the series of average values that detects a clear majority of sample corresponding to either the binary “0” frequency or the binary “1” frequency in order to produce a binary output signal that corresponds to the received signal.Type: GrantFiled: April 22, 1999Date of Patent: August 31, 2004Assignee: 3com CorporationInventor: Zheng-She Liu
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Patent number: 6785348Abstract: In a method for demodulating a CPFSK-modulated signal, the n−1-th substitute symbol an−1 which occurs in the linear approximation of the CPFSK is estimated in order to determine an n-th input data symbol dn on which the CPFSK modulation is based. The n−1-th substitute symbol an−1 is in this case estimated on the basis of the previously determined n−1-th input data symbol {circumflex over (d)}n−1.Type: GrantFiled: December 23, 2002Date of Patent: August 31, 2004Assignee: Infineon Technologies AGInventors: Markus Hammes, Michael Madden, Andre Neubauer, Michael Speth
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Patent number: 6785349Abstract: A correlator for use in a timing recovery apparatus of a receiver in a multicarrier transmission system. The correlator locates the beginning of a data frame and initializes a pointer register with an address to a location within the receive signal buffer. Data is transferred to a signal converter from the receive signal buffer where the samples that are fed into the converter are determined by the address stored in the pointer register.Type: GrantFiled: May 28, 1999Date of Patent: August 31, 2004Assignee: 3Com CorporationInventors: John R. Rosenlof, Kevin J. Smart, John B. Dougall, Jr.
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Patent number: 6785350Abstract: Apparatus, and an associated method, by which to detect a symbol sequence, such as the preamble portion of a frame. Phase calculations are performed, and values of the phase calculations are at least in part determinative of detection of receipt of the symbol sequence. In one implementation, a manner is provided by which to detect reception of the preamble portion of a frame of data broadcast upon a broadcast control channel defined in a HIPERLAN/2 system.Type: GrantFiled: October 14, 1999Date of Patent: August 31, 2004Assignee: Nokia CorporationInventors: Vincent Poulbere, Mika Kasslin
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Patent number: 6785351Abstract: A method is provided for determining the Doppler frequency shift that occurs in the reception of a communication signal when the relative velocity between the transmitted and receiver is unknown. By estimating the channel characteristics and measuring the channel response to known transmitted data bits, a measure of the Doppler frequency is determined according to the method of the invention. In particular, a good estimate of the Doppler frequency shift is obtained based on a second order statistic of the fading process for the channel response to the known transmitted data bits. The approach is simple and general. It applies for any system such as WCDMA and CDMA 2000 when Doppler frequency is needed.Type: GrantFiled: August 16, 2000Date of Patent: August 31, 2004Assignee: Lucent Technologies Inc.Inventor: Robert Caiming Qiu
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Patent number: 6785352Abstract: A method is presented for implementing synchronization between the timing of a first telecommunication system and the timing of a second telecommunication system. A first counter value is regularly updated at a pace determined by the first telecommunication system and a second counter value is regularly updated at a pace determined by the second telecommunication system. At a first time instant the current first counter value is stored. At a second, later time instant the stored counter value is read. Using the read counter value an operational step is timed so that its timing in relation to the timing of the first telecommunication system is known.Type: GrantFiled: February 15, 2000Date of Patent: August 31, 2004Assignee: Nokia Mobile Phones Ltd.Inventor: Jukka Ranta
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Patent number: 6785353Abstract: A method for detecting synchronization loss of the trellis minimum path metric in V.34 modem communications. The invention detects synchronization loss due to bit inversions in trellis decoding in transmitted digital frames due to a periodic inversion pattern that is used for superframe synchronization. The method provides synchronization loss detection by finding the ratio of moving averages for a series of data blocks to the average of a series of inverted 4D symbols located periodically in the beginning and center of received data frames.Type: GrantFiled: September 6, 2000Date of Patent: August 31, 2004Assignee: Telogy Networks, Inc.Inventor: Adrian Zakrzewski
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Patent number: 6785354Abstract: A lock detection method for generating a lock signal including providing a data signal and a clock signal to a clock detection unit, the data signal being describable by an eye pattern, the data signal and the clock signal being in lock when a data transition occurs in the center of a first transition period.Type: GrantFiled: November 28, 2000Date of Patent: August 31, 2004Assignee: Intel CorporationInventor: Casper Dietrich
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Patent number: 6785355Abstract: A method for storing nuclear fuel in a container (10) including a concrete body and a fuel receiver embedded in the concrete body, comprises the steps of: providing formwork (62) for the concrete body and supporting the fuel receiver within the formwork; placing the formwork in an immersed position in a pool (54) containing a body of water; placing concrete in the immersed formwork (62); and removing the formwork with the concrete body cast therein from the pool (52).Type: GrantFiled: October 9, 2002Date of Patent: August 31, 2004Assignee: Oyster International N.V.Inventor: Hans Georgii
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Patent number: 6785356Abstract: The invention relates to a fluoroscopic computed tomography method in which measuring values are continuously acquired so as to be subjected to rebinning and filtering, after which CT images are reconstructed therefrom in a dense temporal sequence. The backprojection comprises the filtered data of fan beams which, while taking into account the data from diametrically oppositely situated zones, cover an overall projection angle range of 180°.Type: GrantFiled: November 13, 2002Date of Patent: August 31, 2004Assignee: Koninklijke Philips Electronics N.V.Inventors: Michael Grass, Thomas Koehler
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Patent number: 6785357Abstract: A non-invasive method and apparatus are described for inspecting a cargo container. The method includes the steps of disposing an X-ray source and an X-ray detector on opposing ends of a rotatable boom, rotating the boom in a horizontal plane so that the X-ray source and X-ray detector straddle the cargo container and providing translational relative movement between the boom and cargo container while the X-ray source irradiates the container and the X-ray detector detects and measures X-ray energy passing through the container from the X-ray source.Type: GrantFiled: January 16, 2003Date of Patent: August 31, 2004Assignee: Bio-Imaging Research, Inc.Inventors: Richard T. Bernardi, John F. Moore