Patents Examined by Khanh Tran
  • Patent number: 7336749
    Abstract: Margin-testing circuits and methods rely upon the statistics of sampled data to explore the margin characteristics of received data. One margining circuit samples an incoming data stream N times at each of many sample points, each sample point representing a unique sample voltage, unique sample timing, or a unique combination of sample voltage and sample timing. The number of ones sampled at a particular point is a measure of the ones probability for that sample point. The ones probabilities for the collection of unique sample points are then analyzed to measure various aspects of the received data stream, including the data margin.
    Type: Grant
    Filed: May 18, 2004
    Date of Patent: February 26, 2008
    Assignee: Rambus Inc.
    Inventor: Bruno W. Garlepp
  • Patent number: 7313177
    Abstract: A system and method for providing reset control between two integrated circuit domains (ICDs) disposed in a synchronous relationship. Upon reset, control signals are generated in a first ICD for resetting driver/receiver circuitry therein in a phased manner. An inter-ICD reset control signal is generated by the first ICD for transmission to the second ICD, wherein the inter-ICD reset control signal is operable to reset the second ICD's driver/receiver circuitry and other components therein.
    Type: Grant
    Filed: July 18, 2003
    Date of Patent: December 25, 2007
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: Rajakrishnan Radjassamy
  • Patent number: 7308015
    Abstract: To decrease the number of base stations transmitting when a mobile station is connected to a plurality of base stations during handover and to let a base station having the best reception quality perform transmission so as to decrease interference in downlink and increase the link capacity. A mobile station periodically measures a pilot signal transmitted from a base station in a reception monitor 406 and estimates its own movement speed at predetermined intervals based upon the reception electric field strength of the pilot signal in a speed estimate device 407 in soft handover state. A time length for measuring the pilot signal transmitted from the base station corresponding to the movement speed and an inner threshold value for deciding transmission base stations during handover are altered in a control section 408.
    Type: Grant
    Filed: June 18, 2001
    Date of Patent: December 11, 2007
    Assignee: NEC Corporation
    Inventors: Nahoko Takano, Kojiro Hamabe
  • Patent number: 7295599
    Abstract: According to one aspect of the invention, a system is provided which includes an adaptive compensation component and a conversion component. The adaptive compensation component performs spectral and linearity compensation on input digital signals to generate output digital signals that are compensated against spectral and linearity variations in the system. The conversion component is coupled to the adaptive compensation component and performs conversion between digital and analog formats. The conversion component receives digital signals generated by the adaptive compensation component and converts the received digital signals to analog format. The conversion component also receives analog signals and converts the received analog signals to digital format for inputted to the adaptive compensation component.
    Type: Grant
    Filed: December 4, 2002
    Date of Patent: November 13, 2007
    Assignee: Ellipsis Digital Systems, Inc.
    Inventor: Murat F. Karsi
  • Patent number: 7295644
    Abstract: Circuits, architectures, a system and methods for clock data recovery. The circuit generally includes (a) a clock phase adjustment circuit, receiving clock phase information and providing a clock phase adjustment signal, (b) a clock frequency adjustment circuit, receiving clock frequency information and providing a clock frequency adjustment signal, and (c) an adder circuit, receiving the clock phase adjustment signal and the clock frequency adjustment signal, and providing a clock recovery adjustment signal. The architectures and/or systems generally comprise those that include a clock data recovery circuit embodying one or more of the inventive concepts disclosed herein. The method generally comprises the steps of (1) sampling the data stream at predetermined times, (2) generating clock frequency information and clock phase information from sampled data, and (3) altering a frequency and/or a phase of the clock signal in response to the clock frequency information and the clock phase information.
    Type: Grant
    Filed: July 14, 2003
    Date of Patent: November 13, 2007
    Assignee: Marvell International Ltd.
    Inventors: Lei Wu, Henri Sutioso
  • Patent number: 7289554
    Abstract: A method and apparatus for efficient filter structure for an enhanced operation of an ADSL-DMT modem on a subscriber loop with an environment consisting of ISDN interference. The method performs equalization of the channel by impulse response shortening and at the same time rejecting interference signals exhibiting cyclostationary properties. The method and apparatus for reducing the crosstalk involves a frequency-shifted versions of the received signal being filtered through frequency-shifted adaptive filters in the appropriate branches, and providing a joint time domain equalizer/crosstalk canceller to perform equalization of the channel and crosstalk cancellation in one instance and a separate crosstalk canceller to cancel crosstalk plus a time domain equalizer to equalize the channel.
    Type: Grant
    Filed: July 15, 2003
    Date of Patent: October 30, 2007
    Assignee: Brooktree Broadband Holding, Inc.
    Inventor: Laurent Francis Alloin
  • Patent number: 7286612
    Abstract: The invention relates to a method of transmitting data from a transmitter to a receiver in a radio system, and to a radio system.
    Type: Grant
    Filed: June 28, 2002
    Date of Patent: October 23, 2007
    Assignee: Nokia Corporation
    Inventors: Juha Ylitalo, Kari Horneman, Marcos Katz, Markku Juntti
  • Patent number: 7286600
    Abstract: A power line carrier communication system can effectively reduce leak electromagnetic field generation. Transmission data is copied on a frequency axis, and vector multiplication of a finite-difference function is performed to insert either a zero signal or an inverted signal between original signals.
    Type: Grant
    Filed: July 16, 2003
    Date of Patent: October 23, 2007
    Assignee: Fujitsu Limited
    Inventors: Hiroyasu Murata, Takashi Kaku
  • Patent number: 7283580
    Abstract: A spread spectrum meter reading system enables the use of high power frequency hopping spread spectrum (HPSS) transmissions at both the encoder transmitter and repeater levels of the meter reading system. A plurality of end point encoder transmitter devices are each connected to a utility meter and transmit high power FHSS signals containing at least metering data for the corresponding utility meter. A plurality of intermediate transceiver units that are fewer in number than the number of end point encoder transmitter devices both receives and retransmits the high power FHSS signals. A base station includes a receiver that receives the high power FHSS signals. Preferably, the base station can receive the high power FHSS signals from both the encoder transmitter devices and the intermediate transceiver units and the intermediate transceiver units aggregates metering data from multiple encoder transmitter devices prior to block retransmission of the metering data to the base station.
    Type: Grant
    Filed: July 23, 2001
    Date of Patent: October 16, 2007
    Assignee: Itron, Inc.
    Inventors: Scott Cumeralto, John MacConnell
  • Patent number: 7283599
    Abstract: The invention relates to a phase error detector which generates a phase correction signal in such a manner that the phase characteristic curve thereof does not have any undesired zero positions and comprises a finite steepness in the angular area around the engaging point. The inventive phase error detector (PFD) calculates the phase correction signal (S) according to the detected decision domain in accordance with a number of predetermined calculating methods. The phase error detector (PFD) attains such an allocation between the decision domains of the complex QAM single state plane and the individual calculating methods such that the static phase characteristic curve thereof does not have any additional zero positions apart from the engaging point.
    Type: Grant
    Filed: June 8, 2000
    Date of Patent: October 16, 2007
    Assignee: Marconi Communications GmbH
    Inventor: Gerhard Herbig
  • Patent number: 7280614
    Abstract: A receiver for a digital data transmission device for receiving a digital signal and comprising a free sampler physically taking samples rk of a received signal r(t) at a frequency at least equal to twice the received signal spectrum maximum frequency. A digital interpolator allows to derive a sequence of samples Xk calculated from said physical samples, according to a tuning parameter ?. An equalizer adjustable to a set of equalization parameters e allows to process said interpolator output samples Xk. A computing unit simultaneously provides, in a single processing, values of ? to the digital interpolator and values of the equalization parameters e to the digital equalizer. The invention also provides a method for digitally processing a received signal in a digital transmission device.
    Type: Grant
    Filed: June 26, 2002
    Date of Patent: October 9, 2007
    Assignee: STMicroelectronics S.A.
    Inventors: Jean-Marc Brossier, Thierry Lenez
  • Patent number: 7280626
    Abstract: Techniques are provided for synthesizing a long coherent I and Q correlation integral at a particular frequency by synthetically combining a sequence of shorter correlation integrals at the same or different frequency. Techniques are also provided for acquiring a carrier-modulated signal with an unknown shift of the carrier frequency, and possibly some additional unknown signal parameters. These techniques involve synthesizing coherent correlation sums at a fine frequency resolution, using coherent correlation sums that are calculated at a coarse frequency resolution. This approach allows for coherent processing of the received signal over an arbitrarily long time interval, while avoiding the excessive computational requirements of traditional methods.
    Type: Grant
    Filed: September 6, 2006
    Date of Patent: October 9, 2007
    Assignee: SiRF Technology, Inc.
    Inventors: Anant Sahai, John Tsitsiklis
  • Patent number: 7277468
    Abstract: The disclosure details a method of measuring the quality of service of broadcast media signals by analyzing digital watermarks embedded in the received broadcast signal. This method enables the quality of the broadcast video or audio signal to be measured without having the original version of the signal before broadcast transmission. Instead, the method analyzes the strength or quality of the embedded digital watermark to determine the quality of the received broadcast signal. The degradation of a watermark signal is used to measure quality of service of broadcast signals, such as audio and video.
    Type: Grant
    Filed: September 10, 2001
    Date of Patent: October 2, 2007
    Assignee: Digimarc Corporation
    Inventors: Jun Tian, Kenneth L. Levy, Hugh L. Brunk
  • Patent number: 7277495
    Abstract: A method and apparatus for data communication in a variety of communication systems using spread spectrum techniques and multilevel sequences in which distinct multilevel sequences used contain binary subsequences that interfere constructively such that synchronous cross-correlation values add constructively. By adding two subsequences from different sets, it is ensured that neither subsequence belongs to the same set. This, in combination with use of correlators, reduces complexity and facilitates increasing the order of a modulation scheme, thus enhancing the bandwidth efficiency.
    Type: Grant
    Filed: January 25, 2001
    Date of Patent: October 2, 2007
    Assignee: Supergold Communication Limited
    Inventor: Timothy O'Farrell
  • Patent number: 7277516
    Abstract: A communication channel delivers a binary signal representing a data sequence by a pattern of high and low logic levels (symbols) from a transmitter to a receiver. The communication channel low-pass filters the transmitter output signal (VX) so that the signal (VR) arriving at the receiver is a distorted version of the transmitted signal. A receiver processes the received signal to produce an output first data signal (Z) representing the sequence of symbols conveyed by the transmitted signal. The receiver filters the received signal with a transfer function controlled by a control signal to produce a compensated signal (X). The receiver responds to trailing edges of the sampling clock signal by driving the first data signal to a succession of first states, wherein each first state corresponds to a separate leading edge of the sampling clock signal and represents a magnitude of the compensated signal on occurrence of the first state's corresponding sampling clock signal leading edge.
    Type: Grant
    Filed: October 14, 2003
    Date of Patent: October 2, 2007
    Assignee: Realtek Semiconductor Corp
    Inventors: Gerchih Chou, Chia-Liang Lin
  • Patent number: 7274746
    Abstract: A system for mitigating noise associated with information communication includes means for determining when a first set of information is transmitted by a transmitter. The system includes a receiver for receiving a second set of information in response to the first set of information. The system also includes control means for temporarily suspending at least one process when the determining means determines that the first set of information is being transmitted and for continuing the at least one process after the second set of information has been received by the receiver. The at least one process produces noise that interferes with an integrity of the second set of information received by the receiver.
    Type: Grant
    Filed: December 24, 2003
    Date of Patent: September 25, 2007
    Assignee: Spirent Communications of Rockville, Inc.
    Inventor: George R. Bailey
  • Patent number: 7274763
    Abstract: The invention relates to an apparatus and a method for ascertaining and correcting the optimum sampling time for an oversampled input bit stream. This involves feeding the data bit blanked with the current sampling phase into the comparative sequence and using the data bit to ascertain a new, corrected sampling phase. This decision-based approach enables the sampling phase to be continuously corrected.
    Type: Grant
    Filed: August 15, 2003
    Date of Patent: September 25, 2007
    Assignee: Infineon Technologies AG
    Inventors: Markus Hammes, Christian Kranz, Johannes Van Den Boom
  • Patent number: 7272177
    Abstract: A transceiver of a communication system is disclosed. The transceiver comprises a front-end receiver for receiving a receiving signal and converting to a first signal with a pre-cursor component and a post-cursor component, a noise canceller coupled to the front-end receiver 10 for generating a second signal through eliminating the noise of the first signal, a Feed-Forward Equalizer (FFE) coupled to the noise canceller for generating a third signal through eliminating the pre-cursor component in the second signal according to a transfer function including a plurality of adjustable constants, wherein the adjustable constants includes a main-tap and the value of the main-tap is predetermined, and a decoding system coupled to the FFE for decoding the third signal and eliminating the post-cursor component in the third signal.
    Type: Grant
    Filed: October 20, 2003
    Date of Patent: September 18, 2007
    Assignee: Realtek Semiconductor Corp.
    Inventors: Hou-Wei Lin, Shieh-Hsing Kuo, Meng-Han Hsieh, Kuang-Yu Yen
  • Patent number: 7272188
    Abstract: A multicarrier signal, which includes a temporal succession of symbols formed by a set of data elements, each of said data elements modulating a carrier frequency of the signal. The data elements include reference elements called pilots, whereof the value in transmission is known to at least one receiver designed to receive the signal and informative data elements, whereof the value in transmission is not known a priori to the at least one receiver. One of the caffier frequencies is modulated, at a given time, by one of the data elements, being called a carrier. At least one constraint is imposed on the value of at least one of the informative data elements, so as to reduce, in reception, at least one term of interference affecting at least one of the pilots.
    Type: Grant
    Filed: September 20, 2001
    Date of Patent: September 18, 2007
    Assignee: France Telecom
    Inventors: Dominique Lacroix-Penther, Pierre Combelles, Michel Alard
  • Patent number: 7269228
    Abstract: A non-coherent frequency shift keying transmitter for up-converting a baseband signal to a radio frequency signal is provided. The non-coherent frequency shift keying transmitter applies the interpolation method in a digital frequency synthesizer to replace the conventional Phase Locked Loop (PLL) circuit. The micro processing unit receives a baseband signal firstly, then the baseband signal is converted to a RF signal via a digital synthesizer, a numerical controlled oscillator, a cascaded integrator-comb filter, and a digital-analog converter. The RF signal is then transmitted via a local oscillator, a band-pass filter, a power amplifier, and a transmitting end. This circuit eliminates unnecessary analog devices so that fabrication migration issue is avoided. Further, the modulated RF signal is more stable than that of the conventional modulator, and has a more efficient spectrum control and a better performance on the receiver end.
    Type: Grant
    Filed: September 29, 2003
    Date of Patent: September 11, 2007
    Assignee: Novatek Microelectronics Corp.
    Inventor: David Shiung