Feedback, Receiver To Transmitter Patents (Class 375/358)
  • Patent number: 7983371
    Abstract: A method is provided for offsetting a reference frequency of a quadrature reference clock signal. A quadrature reference clock (110) generates the quadrature reference clock signal at the reference frequency, while a quadrature variable offset clock (130) generates a quadrature clock signal at a base offset frequency based on a base offset value it receives from a control circuit (560). The base offset value can be determined in many ways, including reading it from a local memory (910) or receiving it from a remote device (1010). A polyphase mixer (140) performs a polyphase mixing operation between the quadrature reference clock signal and the offset clock signal to generate an agile clock signal having an agile clock frequency equal to the reference frequency plus the base offset frequency. If desired, the method can revise the offset frequency based on actual conditions and determine a corresponding revised offset value (920, 1020).
    Type: Grant
    Filed: November 30, 2004
    Date of Patent: July 19, 2011
    Assignee: Freescale Semiconductor, Inc.
    Inventors: John W. McCorkle, Timothy R. Miller
  • Patent number: 7965803
    Abstract: In some embodiments, methods and systems for providing feedback for beamforming include: initializing a weighting vector; determining a perturbation vector; determining a plurality of weighting vectors to be applied to data based on the weighting vector and the perturbation vector; applying the plurality of weighting vectors to the data to provide weighted data; transmitting the weighted data to a receiver; receiving from the receiver a feedback signal based on at least one of the plurality of weighting vectors; and updating the plurality of weighting vectors based on the feedback signal.
    Type: Grant
    Filed: December 14, 2007
    Date of Patent: June 21, 2011
    Assignee: The Trustees of Columbia University in the City of New York
    Inventors: Xiaodong Wang, Filippo Zuccardi Merli
  • Patent number: 7961778
    Abstract: In the context of high-speed serial links, data-dependent jitter compensation techniques performed using phase pre-distortion. Broadly contemplated is an expansion of the notion of pre-emphasis beyond conventional amplitude compensation of ISI, whereby phase pre-emphasis for compensating data-dependent jitter (DDJ) is introduced. DDJ can be addressed by exploiting the relationship between the data sequence and the timing deviation. Phase pre-emphasis improves the signal integrity with little additional power consumption in the transmitter and with no cross-talk penalty.
    Type: Grant
    Filed: July 22, 2008
    Date of Patent: June 14, 2011
    Assignee: International Business Machines Corporation
    Inventors: James F. Buckwalter, Daniel J. Friedman, Mounir Meghelli
  • Patent number: 7953197
    Abstract: There is provided a mobile station device capable of effectively performing interference suppression symbol synthesis while suppressing the lowering of the transfer rate when using the repetition technique in multi-carrier communication. In the mobile station device (100), when the interference level exceeds a threshold value, a switching control unit (110) controls a switch (109) to connect a P/S unit (106) to a weight multiplication unit (113) and controls a switch (111) to connect a channel estimation unit (108) to a weight calculation unit (112). The weight calculation unit (112) calculates an interference suppression weight based on MMSE from a pilot symbol and a channel estimation value. The weight multiplication unit (113) multiplies a data symbol by the interference suppression weight. A synthesis unit (114) synthesizes the data symbol multiplied by the interference suppression weight in repetition unit.
    Type: Grant
    Filed: June 15, 2006
    Date of Patent: May 31, 2011
    Assignee: Panasonic Corporation
    Inventors: Masaru Fukuoka, Sadaki Futagi, Atsushi Matsumoto, Kenichi Miyoshi, Akihiko Nishio
  • Patent number: 7948407
    Abstract: A high-speed serial interface circuit includes a data receiver circuit, a clock signal receiver circuit, a logic circuit block that includes at least a serial/parallel conversion circuit, a free-running clock signal generation circuit, a clock signal detection circuit, and an output mask circuit. The clock signal detection circuit compares a received clock signal from the clock signal receiver circuit with a free-running clock signal from the free-running clock signal generation circuit to detect whether or not clock signals are transferred through differential clock signal lines. When the clock signal detection circuit has detected that the clock signals are not transferred through the differential clock signal lines, the output mask circuit masks an output signal from the logic circuit block so that the output signal is not transmitted to a circuit in the subsequent stage.
    Type: Grant
    Filed: December 30, 2009
    Date of Patent: May 24, 2011
    Assignee: Seiko Epson Corporation
    Inventors: Takemi Yonezawa, Kenichi Oe
  • Patent number: 7949066
    Abstract: A method and apparatus for transmitting digital data in a cellular environment. Adjacent cells of the cellular system are prevented from simultaneously transmitting data. Because the noise from transmissions of adjacent cells is a primary source of interference, the transmission rate of power limited base stations can be dramatically increased when the noise from adjacent cells is eliminated. The transmissions to each subscriber station are made at a fixed transmission power level. However, the data rate of transmitted signals differs from one subscriber station to another depending the path loss differences. In a first exemplary embodiment, the data rate of transmissions to a subscriber station is determined by selecting an encoding rate for the transmitted signal while holding the symbol rate constant.
    Type: Grant
    Filed: March 29, 2002
    Date of Patent: May 24, 2011
    Assignee: QUALCOMM Incorporated
    Inventor: Ephraim Zehavi
  • Patent number: 7940851
    Abstract: A radio communication apparatus and an associated method are provided. The apparatus includes a receiving unit configured to receive first data and second data, which are transmitted from a plurality of antennas for spatial-multiplexing using a plurality of blocks, into which a plurality of consecutive subcarriers in a frequency domain are divided. The apparatus further includes a calculating unit configured to calculate a first absolute CQI value per each of the blocks for the first data and a second absolute CQI value per each of the blocks for the second data, and calculate a relative value of the second absolute CQI value with respect to the first absolute CQI value, per each of the blocks. The apparatus still further includes a transmitting unit configured to transmit the first absolute CQI value and the relative value of the second absolute CQI value in the same block.
    Type: Grant
    Filed: April 21, 2006
    Date of Patent: May 10, 2011
    Assignee: Panasonic Corporation
    Inventors: Jinsong Duan, Keisuke Ebiko, Ryohei Kimura
  • Patent number: 7940869
    Abstract: Radio communication system includes terminal including unit detecting radar wave transmitted through second-frequency channel, first-and-second-frequency channels through which radar wave fails to be transmitted being simultaneously utilized or one of first-and-second-frequency channels being utilized, unit generating radar-detection information including information indicating detection time when detecting unit detects radar wave, and information indicating frequency channel through which radar wave is transmitted, and unit transmitting radar-detection information, and base station including unit receiving radar-detection information, unit generating radar-occurrence information based on received-radar-detection information, radar-occurrence information including information indicating occurrence time when radar wave occurs, information indicating period of occurrence of radar wave, and information indicating frequency channel through which radar wave is transmitted, and unit transmitting radar-occurrence in
    Type: Grant
    Filed: February 2, 2006
    Date of Patent: May 10, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomoya Tandai, Tomoko Adachi, Yoriko Utsunomiya, Daisuke Takeda, Kazumi Sato, Koji Ogura
  • Patent number: 7920010
    Abstract: A logic signal isolator comprising a transformer having a primary winding and a secondary winding; a transmitter circuit which drives said primary winding in response to a received logic signal, such that in response to a first type of edge in the logic signal, a signal of a first predetermined type is supplied to the primary winding and in response to a second type of edge in the logic signal, a signal of a second predetermined type is supplied to said primary winding, the primary winding and the transmitter being referenced to a first ground; and the secondary winding being referenced to a second ground which is galvanically isolated from the first ground and said secondary winding supplying to a receiver circuit signals received in correspondence to the signals provided to the primary winding, the receiver reconstructing the received logic signal from the received signals.
    Type: Grant
    Filed: November 10, 2009
    Date of Patent: April 5, 2011
    Assignee: Analog Devices, Inc.
    Inventors: Baoxing Chen, Jr., Geoffrey Haigh
  • Patent number: 7903775
    Abstract: A method, a related system, and recordable media adapted to store the method. The method controlling transmission frequency for first and second transmission signals exchanged between a host and an attached device using a serial advanced technology attachment (SATA) technology by detecting a first transmission frequency from a received first transmission signal, and controlling a second transmission frequency for a second transmission signal in relation to the detected first transmission frequency.
    Type: Grant
    Filed: February 28, 2007
    Date of Patent: March 8, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Young-Min Ku, Ho-Joong Choi
  • Patent number: 7894505
    Abstract: An apparatus and method for selecting an effective channel in a multi-user MIMO system are provided, in which a receiver receives pilot signals from a transmitter, determines channel information indicating an antenna offering the best quality among a plurality of antennas using the pilot signals, and generates feedback information with the channel information, and the transmitter receives feedback information from a plurality of receivers, generates a channel matrix using the feedback information, and transmits data simultaneously to the plurality of receivers using the channel matrix.
    Type: Grant
    Filed: April 19, 2007
    Date of Patent: February 22, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Yong-Xing Zhou, Sung-Jin Kim, JianJun Li, Ho-Jin Kim
  • Patent number: 7895044
    Abstract: A codebook generation system and associated methods are generally described herein. For instance, a codebook generation agent (CGA) may implement techniques for generating one or more matrix codebooks from vector codebooks. The CGA may be implemented in mobile devices (e.g., stations, subscriber units, handsets, laptops, etc.). In this regard, the dynamic generation of matrix codebooks rather than having them stored on the mobile device enables the mobile device to utilize the memory normally consumed by the matrix codebooks in support of other features and/or services.
    Type: Grant
    Filed: February 16, 2005
    Date of Patent: February 22, 2011
    Assignee: Intel Corporation
    Inventors: Xintian E. Lin, Qinghua Li
  • Patent number: 7894510
    Abstract: Nonlinearity characterization that transmits bursts of information where symbols vary by a value Delta. The bursts can be bursts of a constant power, followed by another burst of a different constant power. An alternative burst system uses interleaved power symbols, where some symbols in a single burst are at the first power and others are at the second power. The signal-to-noise ratio of the two groups of symbols is estimated, and the difference is used to determine whether or not to reduce the amount of saturation in the transmitter.
    Type: Grant
    Filed: July 2, 2007
    Date of Patent: February 22, 2011
    Assignee: ViaSat, Inc.
    Inventors: Mark J. Miller, Aniruddha Das, Robert A. Fitting
  • Patent number: 7885250
    Abstract: A method and apparatus for synchronizing timing of Access Points (APs) and/or Synchronization Units (SUs) includes (a) arranging a cable having at least four pairs of twisted wires connected between two or more fixed APs and/or SUs in a network; (b) assigning a first pair of the twisted wires to carry a positive D.C. voltage to at least one AP or SU; (C) assigning a second pair of the twisted wires to carry a negative D.C. voltage to at least one AP or SU; (d) providing to the first and second pairs of rails a series of synchronization pulses generated from a synchronization source and capacitively-coupled to the first and second pairs of twisted wires so as to supply a composite signal; and (e) reconstructing the generated synchronization pulses by detecting pulses on the positive and negative D.C. voltages at a receiving end by at least one AP or SU.
    Type: Grant
    Filed: February 3, 2005
    Date of Patent: February 8, 2011
    Assignee: Koninklijke Philips Electronics N.V.
    Inventor: Tim Whittaker
  • Patent number: 7881401
    Abstract: A transmitter arrangement includes a first and a second phase-locked loop, each having a power amplifier. The first phase-locked loop generates a first amplified oscillator signal depending on a first input signal representing a first phase information, wherein a first feedback signal for the first phase-locked loop is derived from the first amplified oscillator signal. Accordingly, the second phase-locked loop generates a second amplified oscillator signal depending on a second input signal representing a second phase information. A second feedback signal for the second phase-locked loop is derived from the second amplified oscillator signal. The transmitter arrangement further includes a summation element to combine the amplified first oscillator signal and the amplified second oscillator signal to an output signal.
    Type: Grant
    Filed: November 17, 2006
    Date of Patent: February 1, 2011
    Assignee: Infineon Technologies AG
    Inventors: Gunther Kraut, Junqi Liu, Qi Yu
  • Patent number: 7881400
    Abstract: A pulse modulation type transmitter apparatus and a pulse modulation type receiver apparatus wherein both a fast synchronization establishment and a low power consumption of a synchronizing part can be achieved at the same time and wherein the data transmission/reception can be performed soon after a commencement of communication, and further a fast data transmission and a low power consumption can be achieved. A first template signal (1006), which is generated based on a separately transmitted RF frame synchronization signal (1005), is used to generate a frame synchronization signal (1009), and a second frame synchronization timing adjusting part (150) is used to synchronize the frame synchronization signal (1009) with a received RF data signal (1004). Then, a synchronization detection is performed, whereby a prompt pulse acquisition and a prompt pulse phase acquisition can be achieved.
    Type: Grant
    Filed: May 8, 2006
    Date of Patent: February 1, 2011
    Assignee: Panasonic Corporation
    Inventors: Suguru Fujita, Masahiro Mimura, Kazuaki Takahashi, Yoshinori Kunieda, Noriyuki Ueki
  • Patent number: 7876866
    Abstract: A method and apparatus are provided for reducing, and preferably substantially eliminating, data-pattern autocorrelations found in digital communication systems. The method employed is referred to as Data Subset Selection (DSS) and is implemented in the form of DSS engine. Autocorrelations in the data-pattern can cause many digital adaptive systems to converge to an incorrect solution. For example, the LMS method, which is often used in adaptive filtering applications, can converge to an incorrect set of filter coefficients in the presence of data-pattern autocorrelations. Digital timing recovery methods are also susceptible. Other impairments that result from data-pattern autocorrelations include increased convergence time and increased steady-state chatter.
    Type: Grant
    Filed: January 26, 2006
    Date of Patent: January 25, 2011
    Assignee: PMC-Sierra US, Inc.
    Inventors: Matthew W. McAdam, Jurgen Hissen, Graeme Boyd
  • Patent number: 7873099
    Abstract: Time is transferred from an ultra wideband (UWB) transmitter to UWB receiver by transmitting a signal structure having an associated timing reference point together with a time value for the timing reference point. The UWB receiver receives the timing signal structure by synchronizing a receiver time base to the signal structure, demodulating the time value information, and using the demodulated time value information to set a receiver clock value. Propagation delay information is used to adjust the receiver clock value by advancing the receiver clock value to account for the propagation delay. In one embodiment, propagation delay is determined from a known distance between the transmitter and receiver. In another embodiment, the transmitter and receiver are part of a two-way link wherein propagation delay is measured by round trip timing measurements.
    Type: Grant
    Filed: October 31, 2007
    Date of Patent: January 18, 2011
    Assignee: Time Domain Corporation
    Inventors: Larry W. Fullerton, Mark D. Roberts, James L. Richards
  • Patent number: 7860204
    Abstract: Communication device for processing outgoing and incoming packets. The device includes a plurality of signal processing units connected in sequence, each signal processing unit being clocked by a common clock signal. The device further includes a mode line connected to each signal processing unit for switching each signal processing unit between a transmit mode and a receive mode. The device further includes a control line to which each signal processing unit is connected. The control line communicating flow control information either in the transmit mode to at least one of the preceding signal processing units or in the receive mode to at least one of the following signal processing units.
    Type: Grant
    Filed: July 3, 2003
    Date of Patent: December 28, 2010
    Assignee: International Business Machines Corporation
    Inventors: Simeon Furrer, Dietrich Maiwald, Wolfgang H. Schott
  • Patent number: 7856374
    Abstract: Methods and apparatuses for manufacturer to present Web-based edu-games so as to train retail staff member about the manufacturer and its products and to access edu-game data and retail sales data from a database. A Website can be created to provide a point of interaction between the manufacturer, retailer, and retail staff member. By accessing this Website, the retail staff member is presented with the web-based edu-games and learns about the manufacturer and its products. The retail staff member can be presented with incentives by the manufacturer for completing the web-based training off time, which may prevent the retailer from paying for the costs of training the retail staff member. Alternately, retailers can also do training in-house (e.g., if required by statute). Manufacturers and retailers compare education levels to sales data to determine the effects of the training.
    Type: Grant
    Filed: January 19, 2005
    Date of Patent: December 21, 2010
    Assignee: 3Point5
    Inventor: Paul Kirwin
  • Patent number: 7839851
    Abstract: A method, apparatus and system for opportunistic multicasting are described.
    Type: Grant
    Filed: December 17, 2007
    Date of Patent: November 23, 2010
    Assignee: NTT Docomo, Inc.
    Inventor: Ulas C. Kozat
  • Patent number: 7839965
    Abstract: A clock generator is provided for a transmitter in a transceiver adapted to communicate data over a serial data link. The transceiver includes a clock data recovery circuit recovers a receive clock signal and outputs a reference clock signal. The clock generator includes a local clock, a frequency difference detector, and a fractional-N frequency synthesizer. The local clock outputs a local clock signal. The frequency difference detector outputs a fractional frequency difference signal based on a frequency difference between the local clock signal and the reference clock signal. The fractional-N frequency synthesizer outputs a transmit clock signal having a same frequency as the recovered receive clock signal.
    Type: Grant
    Filed: November 21, 2006
    Date of Patent: November 23, 2010
    Assignee: Agere Systems Inc.
    Inventors: William B. Wilson, Kenneth Wade Paist
  • Patent number: 7826580
    Abstract: An audio network system that performs transport of audio signals among nodes by cascading a plurality of nodes each including two sets of transmission I/Fs and reception I/Fs, and circulating among the nodes in each fixed period an audio transport frame generated by a master node, the audio transport frame including a plurality of storage regions for audio signals, is configured such that the master node measures time periods Dfw and Dbw after the audio transport frame is transmitted until the audio transport frame returns to the master node after passing through the transmission route and writes them into the audio transport frame, and each of the other nodes generates a signal processing wordclock based on those time periods, two reception times Tr1 and Tr2 while the audio transport frame circulates once through the transmission route, and a predetermined target time Tt.
    Type: Grant
    Filed: September 13, 2007
    Date of Patent: November 2, 2010
    Assignee: Yamaha Corporation
    Inventors: Kei Nakayama, Naoto Yamaguchi
  • Patent number: 7823001
    Abstract: In emulation systems having a plurality of chips, data communicated between the chips needs to be synchronized. A receiver chip may push or pull on incoming data from an emitter chip in order to synchronize it with a receiver clock. Unexpected latency on the link between the emitter and receiver chips may also be adjusted for.
    Type: Grant
    Filed: October 27, 2006
    Date of Patent: October 26, 2010
    Assignee: Mentor Graphics (Holdings) Ltd.
    Inventors: Jean-Paul Clavequin, Pascal Couteaux, Philippe Diehl
  • Patent number: 7817568
    Abstract: Provided are a method for measuring characteristics of a path between nodes by using active testing packets based on priority, i.e., an inter-node path characteristic measuring method, which can measure and provide characteristics of a generated node, when an inter-node data transmission path is generated based on Multi-Protocol Label Switching (MPLS) to provide a path with satisfactory transmission delay, jitter and packet loss that are required by a user, and to provide a computer-readable recording medium for recording a program that implement the method. The method includes the steps of: a) synchronizing system time of the nodes with a global standard time; b) forming each testing packet; c) registering frame sequence and the global standard time during transmission; and d) calculating transmission delay time, jitter and packet loss by using time stamp and packet sequence information of a frame received by the destination node and transmitting the result to the management system.
    Type: Grant
    Filed: May 7, 2004
    Date of Patent: October 19, 2010
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Euihyun Paik, Tae-Il Kim, Hyeong-Ho Lee
  • Patent number: 7801202
    Abstract: A slave low power radio frequency transceiver participates in a network controlled by a master low power radio frequency transceiver and synchronises its timing to the network timing by receiving radio packets transmitted from the controlling low power radio frequency transceiver. The slave transceiver comprises timing means; detection means operable over an interval of time for detecting a predetermined portion of a received radio packet; and adjusting means for adjusting the timing means in response to the detection of a predetermined portion of a received radio packet. The slave low power radio frequency transceiver is arranged to controllably vary the duration of the interval of time.
    Type: Grant
    Filed: November 13, 2002
    Date of Patent: September 21, 2010
    Assignee: Nokia Corporation
    Inventors: Thomas Block, Christian Zechlin, Dietmar Schnepp
  • Patent number: 7793021
    Abstract: A method for synchronizing a transmission of information over a bus, and a device having synchronization capabilities.
    Type: Grant
    Filed: January 5, 2006
    Date of Patent: September 7, 2010
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Michael Priel, Dan Kuzmin, Amir Zaltzman
  • Patent number: 7764737
    Abstract: An embodiment of the present invention includes a receiver, and a selector. The receiver receives a default stream and N restart sub-streams from a transmitter over a transmission path, N is an integer equal to at least 1 and is selected according to a selection. The default stream is coded by a multiple description (MD) coding. The N restart sub-streams are coded by a predictive coding and sampled according to a sampling pattern. The default and N restart sub-streams correspond to a media content. The selector selects a receiving stream from the default stream and one of the N restart sub-streams according to a loss status in the default stream.
    Type: Grant
    Filed: March 31, 2004
    Date of Patent: July 27, 2010
    Assignees: Sony Corporation, Sony Electronics Inc.
    Inventors: Ezra Jacques Elie Eric Setton, Atsushi Shionozaki
  • Patent number: 7746964
    Abstract: A signal processing apparatus includes a plurality of equalizer each used for a corresponding frequency band, controller for setting a gain value in each of the plurality of equalizer, and signal processor for processing an input signal by means of the plurality of equalizer. The controller determines a target gain value for each of the plurality of frequency bands, obtains a value of gain leakage from the first frequency band to a second frequency band adjacent to the first frequency band, updates a gain value set for the second frequency band, updates a gain value set for the first frequency band, repeats an update process for updating the gain value for each of the first frequency band and the second frequency band in an alternate manner until the gain value satisfies a predetermined condition, and sets the updated gain value for each of the frequency bands in the corresponding equalizer.
    Type: Grant
    Filed: December 4, 2006
    Date of Patent: June 29, 2010
    Assignee: Sony Corporation
    Inventor: Kenji Nakano
  • Patent number: 7742534
    Abstract: The present invention relates to a method for transmitting user data between a transmitter and a receiver in a multi-carrier radio communication system having a plurality of orthogonal frequency sub-carriers, said method comprising the steps of selecting a set of sub-carriers on which said user data are to be transmitted between said transmitter and said receiver. According to the present invention, the method comprises the steps of: Sending from said transmitter, before transmission of said user data, an indication related to a threshold; Determining at the receiver a quality level for each sub carriers; Selecting at said receiver sub carriers to received said user data as a function of said indication related to a threshold and of said quality levels.
    Type: Grant
    Filed: July 11, 2006
    Date of Patent: June 22, 2010
    Assignee: Alcatel Lucent
    Inventors: Stephen Kaminski, Ralph Ballentin
  • Patent number: 7729454
    Abstract: Aspects of a method and system for signal phase variation detection in communication systems are presented. Aspects of the system may enable detection of phase change between a current received symbol, and one or more previous received symbols. Based on the phase change a channel estimation filter bandwidth may be selected for despreading and/or descrambling one or more subsequent received symbols. In addition, a decision may be made as to whether the subsequent received symbols are to be received based on a closed loop system, or based on an open loop system.
    Type: Grant
    Filed: November 30, 2006
    Date of Patent: June 1, 2010
    Assignee: Broadcom Corporation
    Inventors: Li Fung Chang, Hongwei Kong, Nelson Sollenberger
  • Patent number: 7729464
    Abstract: An apparatus and method of aiding synchronization between a master transceiver and a slave transceiver is disclosed. The method includes the master transceiver transmitting data signals that are received by the slave transceiver. The slave transceiver locks a slave clock to the data signals with a slave phase-locked loop. The slave transceiver transmits slave clock information to the master transceiver.
    Type: Grant
    Filed: December 22, 2006
    Date of Patent: June 1, 2010
    Assignee: Teranetics, Inc.
    Inventors: Dimitry Taich, Jose Tellado
  • Patent number: 7724858
    Abstract: Method and apparatus to manage delay for multiple receivers for a wireless system are described.
    Type: Grant
    Filed: November 29, 2004
    Date of Patent: May 25, 2010
    Assignee: Intel Corporation
    Inventors: Qinghua Li, Xintian E. Lin
  • Patent number: 7715471
    Abstract: An integrated circuit having a receiver that selectively inhibits incoming data from being used to update adaptively generated controls. Sampling circuitry generates a plurality of samples of an incoming signal. Control circuitry generates an inhibit signal in either a first state or a second state according to whether the plurality of samples meets a randomness criterion. Tap weight update circuitry receives the inhibit signal from the control circuitry and updates a plurality of equalizer tap weights based on the plurality of samples if the inhibit signal is in the first state. The tap weight update circuitry refrains from updating the plurality of equalizer tap weights based on the plurality of samples if the inhibit signal is in the second state.
    Type: Grant
    Filed: December 24, 2004
    Date of Patent: May 11, 2010
    Assignee: Rambus, Inc.
    Inventors: Carl W. Werner, Andrew Ho
  • Patent number: 7706998
    Abstract: Systems and methods for synchronizing communication between devices include using a test circuit to measure a propagation time through a delay circuit. The propagation time is used to determine an initial delay value within a delay lock loop. This delay value is then changed until a preferred delay value, resulting in synchronization, is found. In various embodiments, used of the initial delay value increases the speed, reliability or other beneficial features of the synchronization.
    Type: Grant
    Filed: September 10, 2007
    Date of Patent: April 27, 2010
    Assignee: Rambus Inc.
    Inventors: Adrian E. Ong, Douglas W. Gorgen
  • Patent number: 7706823
    Abstract: A method of synchronizing a base station of a wireless communication system and a subscriber communication equipment located in the coverage area of the base station by compensating a sampling frequency offset in the subscriber equipment by interpolating input and/or output signals of a radio frequency part of the communication equipment to generate samples corresponding to the original symbol timing of the base station, and compensating the carrier frequency offset from the estimate of the sampling clock error.
    Type: Grant
    Filed: June 30, 2006
    Date of Patent: April 27, 2010
    Assignee: Sequans Communications
    Inventors: Fabien Buda, Emmanuel Lemois, Bertrand Debray
  • Patent number: 7706428
    Abstract: Inter-carrier interference (ICI) in a kth sub-carrier of an orthogonal frequency division multiplexing (OFDM) signal received at time t is reduced, wherein the received OFDM signal comprises a plurality of sub-carriers. This is achieved by generating a self-interference term, ICIk?L,k?L, for a signal received on sub-carrier k?L, wherein L ? [ . . . , ?3,?2,?1,1,2,3, . . . ], and wherein the self-interference term is an estimate of the data received at time t on the sub-carrier k?L, weighted by a rate of change of the channel through which sub-carrier k?L passes at time t. An ICI cancellation coefficient, GL is obtained, and an estimated ICI term is generated by adjusting the self-interference term, ICIk?L,k?L, by an amount based on the ICI cancellation coefficient, GL. The estimated ICI term is then subtracted from a term representing a signal received on the kth sub-carrier at time t.
    Type: Grant
    Filed: February 10, 2006
    Date of Patent: April 27, 2010
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Leif Wilhelmsson, Michael Faulkner
  • Patent number: 7702284
    Abstract: A method and system of controlling a multicast transmission. The method and system transmits a data packet to multiple slave devices across a UWB wireless network, and detects the reception of any acknowledgement transmissions. These acknowledgement transmissions indicate reception of the data packet by the slave devices. In addition, the method and system retransmit the data packet to at least one of the slave devices when an acknowledgment is not detected for each of the slave devices. The acknowledgments may be received from the UWB network.
    Type: Grant
    Filed: September 12, 2003
    Date of Patent: April 20, 2010
    Inventors: Arto Palin, Juha Salokannel, Jukka Reunamäki
  • Patent number: 7697910
    Abstract: A signal receiver and a method for separating a RDS signal component from a received signal is described. After the received signal has been downconverted to the baseband, the baseband signal is split up into a first baseband signal for a first signal path and a second baseband signal for a second signal path. The first baseband signal is highpass filtered and forwarded to a frequency synchronization unit that generates a frequency synchronization carrier. The second baseband signal is modified in accordance with the frequency synchronization carrier provided by the first signal path, and a synchronized baseband signal is obtained that still comprises the full range of the RDS signal's spectral components.
    Type: Grant
    Filed: December 19, 2003
    Date of Patent: April 13, 2010
    Assignee: Sony Deutschland GmbH
    Inventor: Jens Wildhagen
  • Patent number: 7693032
    Abstract: An arrangement is disclosed where in a multi-carrier communication system, the modulation scheme, coding attributes, training pilots, and signal power may be adjusted to adapt to channel conditions in order to maximize the overall system capacity and spectral efficiency without wasting radio resources or compromising error probability performance.
    Type: Grant
    Filed: February 14, 2005
    Date of Patent: April 6, 2010
    Assignee: Neocific, Inc.
    Inventors: Xiaodong Li, Titus Lo, Kemin Li, Haiming Huang
  • Patent number: 7692444
    Abstract: A logic signal isolator comprising a transformer having a primary winding and a secondary winding; a transmitter circuit which drives said primary winding in response to a received logic signal, such that in response to a first type of edge in the logic signal, a signal of a first predetermined type is supplied to the primary winding and in response to a second type of edge in the logic signal, a signal of a second predetermined type is supplied to said primary winding, the primary winding and the transmitter being referenced to a first ground; and the secondary winding being referenced to a second ground which is galvanically isolated from the first ground and said secondary winding supplying to a receiver circuit signals received in correspondence to the signals provided to the primary winding, the receiver reconstructing the received logic signal from the received signals.
    Type: Grant
    Filed: July 6, 2006
    Date of Patent: April 6, 2010
    Assignee: Analog Devices, Inc.
    Inventors: Baoxing Chen, Geoffrey Haigh
  • Patent number: 7684527
    Abstract: There is provided a radio communication device having a high quality and accuracy regardless of fluctuation degree of the transmission path characteristic. The radio communication device estimates the fluctuation speed of the transmission path characteristic from the time correlation of the reception signal, judges the diversity technique used between the communication devices from the estimated value, and feeds back the judgment information so as to switch the diversity between the communication devices, thereby increasing the diversity gain. The feedback information is minimized by defining a correspondence table. Moreover, diversity switching is performed at a timing considering a control delay and a propagation path delay so as to prevent an instantaneous disconnection of the communication.
    Type: Grant
    Filed: September 14, 2007
    Date of Patent: March 23, 2010
    Assignee: Fujitsu Limited
    Inventor: Hitoshi Yokoyama
  • Patent number: 7684532
    Abstract: A programmable logic device (“PLD”) is augmented with programmable clock data recover (“CDR”) circuitry to allow the PLD to communicate via any of a large number of CDR signaling protocols. The CDR circuitry may be integrated with the PLD, or it may be wholly or partly on a separate integrated circuit. The circuitry may be capable of CDR input, CDR output, or both. The CDR capability may be provided in combination with other non-CDR signaling capability such as non-CDR low voltage differential signaling (“LVDS”). The circuitry may be part of a larger system.
    Type: Grant
    Filed: April 25, 2007
    Date of Patent: March 23, 2010
    Assignee: Altera Corporation
    Inventors: Edward Aung, Henry Lui, Paul Butler, John Turner, Rakesh Patel, Chong Lee
  • Patent number: 7683654
    Abstract: A logic signal isolator comprising a transformer having a primary winding and a secondary winding; a transmitter circuit which drives said primary winding in response to a received logic signal, such that in response to a first type of edge in the logic signal, a signal of a first predetermined type is supplied to the primary winding and in response to a second type of edge in the logic signal, a signal of a second predetermined type is supplied to said primary winding, the primary winding and the transmitter being referenced to a first ground; and the secondary winding being referenced to a second ground which is galvanically isolated from the first ground and said secondary winding supplying to a receiver circuit signals received in correspondence to the signals provided to the primary winding, the receiver reconstructing the received logic signal from the received signals.
    Type: Grant
    Filed: December 27, 2007
    Date of Patent: March 23, 2010
    Assignee: Analog Devices, Inc.
    Inventors: Baoxing Chen, Geoffrey Haigh
  • Publication number: 20100067631
    Abstract: A method for data bridging and synchronization between a mobile device and a computer network, using a computer connected to the mobile device over a short range communication channel.
    Type: Application
    Filed: September 17, 2009
    Publication date: March 18, 2010
    Inventors: Rafael Ton, Yoad Gidron
  • Patent number: 7680198
    Abstract: A bit/power loading method in an adaptive modulation-based multicarrier communication system computes ratios of modulation mode values to transmission power values sub-channel-by-sub-channel, selects a combination of sub-channels in which a sum of the ratios is maximized for a total number of bits to be simultaneously transmitted, and transmits signals in modulation modes corresponding to ratios of modulation mode values to transmission power values associated with the selected sub-channels. Because the bit/power loading method selects a combination of sub-channel modulation modes with the minimum total transmission power for a given number of bits on the basis of transmission power in each sub-channel modulation mode, the bits can be transmitted at the minimum transmission power in a given environment.
    Type: Grant
    Filed: March 24, 2005
    Date of Patent: March 16, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Pandharipande Ashish, Ho Yang, Hyoung-Woon Park, Ho-Jin Kim, Young-Ho Jung
  • Patent number: 7668200
    Abstract: The present invention provides a method for controlling transmission latency in a communications system, wherein the communications system is subject to a noise signal having at least a first noise phase and a second noise phase. The method includes determining a first bit rate for symbols transmitted during the first noise phase, and a second bit rate for symbols transmitted during the second noise phase, the first bit rate and the second bit rate being constrained such that a transmission latency does not exceed a pre-determined maximum allowed transmission latency; and transmitting symbols at the first bit rate during the first noise phase and at the second bit rate during the second noise phase. In other variants, the invention provides an apparatus, a constrained rate receiver, a transmitter and a signal.
    Type: Grant
    Filed: June 30, 2004
    Date of Patent: February 23, 2010
    Assignee: Broadcom Corporation
    Inventors: Richard Greenfield, Miguel Peeters
  • Patent number: 7663515
    Abstract: A high-speed serial interface circuit includes a data receiver circuit, a clock signal receiver circuit, a logic circuit block that includes at least a serial/parallel conversion circuit, a free-running clock signal generation circuit, a clock signal detection circuit, and an output mask circuit. The clock signal detection circuit compares a received clock signal from the clock signal receiver circuit with a free-running clock signal from the free-running clock signal generation circuit to detect whether or not clock signals are transferred through differential clock signal lines. When the clock signal detection circuit has detected that the clock signals are not transferred through the differential clock signal lines, the output mask circuit masks an output signal from the logic circuit block so that the output signal is not transmitted to a circuit in the subsequent stage.
    Type: Grant
    Filed: August 22, 2008
    Date of Patent: February 16, 2010
    Assignee: Seiko Epson Corporation
    Inventors: Takemi Yonezawa, Kenichi Oe
  • Patent number: 7664521
    Abstract: In the mobile communication system, a total reception quality between a terminal and a base station is converged into a target quality, thereby suppressing a period in which the transmission power of a distant station becomes excessive.
    Type: Grant
    Filed: February 17, 2005
    Date of Patent: February 16, 2010
    Assignee: NEC Corporation
    Inventor: Kazuhiro Arimitsu
  • Patent number: 7660366
    Abstract: Methods and apparatus to communicate between a local component and a remote component, where the local component is connected to the remote component using a non-deterministic communication link. A local clock is synchronized with a remote clock to within a maximum offset. A rate message from the remote component is received at the local component, where the rate message includes a first time stamp. A data rate is adjusted using the rate message when the time of the local clock substantially matches a time determined using the first time stamp. A data message is sent to the remote component using the adjusted data rate, where the data message includes a second time stamp for use in processing data in the data message. In some implementations, the time determined using the first time stamp is also determined using information about a communication link delay and/or a clock offset.
    Type: Grant
    Filed: August 30, 2004
    Date of Patent: February 9, 2010
    Assignee: Harmonic Inc.
    Inventors: Martin Raptis Picco, Noam Koren