Phase Displacement, Slip Or Jitter Correction Patents (Class 375/371)
-
Patent number: 8638884Abstract: The data processing unit (15) for a receiver of signals carrying information (1) includes a clock and data recovery circuit (16) on the basis of a data signal (DOUT), and a processor circuit (17) connected to the clock and data recovery circuit. The clock and data recovery circuit is clocked by a local clock signal (CLK) and includes a numerical phase lock loop, in which a numerically controlled oscillator (25) is arranged. This numerically controlled oscillator generates an in-phase pulse signal (IP) and a quadrature pulse signal (QP) at output. The frequency and phase of the pulse signals IP and QP are adapted on the basis of the received data signal (DOUT). The processor circuit is arranged to calculate over time the mean and variance of the numerical input signal (NCOIN) of the numerically controlled oscillator (25), so as to determine the coherence of the data signal if the calculated mean and variance are below a predefined coherence threshold.Type: GrantFiled: October 19, 2011Date of Patent: January 28, 2014Assignee: The Swatch Group Research and Development LtdInventor: Arnaud Casagrande
-
Patent number: 8638895Abstract: In one embodiment, receiving an Ethernet signal over a channel, the Ethernet signal comprising a preamble frame, an idle frame, and a data frame, the preamble frame comprising one or more preamble codes; synchronizing to the Ethernet signal based on the preamble frame; replicating the one or more preamble codes; and training a decision feedback equalizer (DFE) based on the one or more replicated codes, the training enabling the DFE to use decision values at the DFE output to track channel variations.Type: GrantFiled: March 1, 2012Date of Patent: January 28, 2014Assignee: Broadcom CorporationInventors: Ahmad Chini, Mehmet Tazebay, Scott Powell
-
Patent number: 8638841Abstract: A transmitting/receiving system includes two transmitting/receiving apparatuses connected through a transmission cable having two one-direction signal lines. Each apparatus includes a transmitting unit that transmits a signal, a receiving unit that receives a signal, a calculator, a controller, a storage, and an estimating unit. The calculator calculates an Signal to Noise (S/N) ratio of the received signal. The controller controls the calculation by obtaining, as a first value, a strength of a signal caused by a check signal transmitted during absence of a check signal being received, obtaining, as a second value, a strength of a check signal received during absence of a check signal being transmitted, and dividing the second value by the first value. The storage stores relationship between a predetermined transmission-cable S/N ratio and temporal signal fluctuation. The estimating unit estimates temporal signal fluctuation from the calculated S/N ratio and the relationship.Type: GrantFiled: August 10, 2012Date of Patent: January 28, 2014Assignee: Fuji Xerox Co., Ltd.Inventor: Yasuaki Konishi
-
Patent number: 8634512Abstract: A two point modulation digital phase locked loop circuit is disclosed. The circuit includes a sampling clock input that is switchable between a plurality of frequencies. The circuit also includes a sigma-delta modulator in a feedback path that receives low-pass modulation data. The circuit also includes a voltage-mode digital-to-analog converter (VDAC) that receives high-pass modulation data. The circuit also includes an analog voltage controlled oscillator coupled to the feedback path and the output of the VDAC. The circuit also includes a phase-to-digital converter (PDC) coupled to the feedback path, the sampling clock and a loop filter.Type: GrantFiled: February 8, 2011Date of Patent: January 21, 2014Assignee: QUALCOMM IncorporatedInventors: Lai Kan Leung, Chiewcharn Narathong
-
Patent number: 8634504Abstract: A correlation calculating method of correlating a received code signal obtained by demodulating a received signal, which is a signal obtained by receiving a positioning satellite signal, with a replica code signal is provided which includes: correlating values of the replica code signal in a chip period with values of the received code signal at first to n-th arrival times obtained by varying an arrival time of the chip period by 1/n chip (where n is an integer equal to or greater than 2); and acquiring a correlation calculation result at a 1/n chip interval by synthesizing the correlation calculation results.Type: GrantFiled: March 22, 2011Date of Patent: January 21, 2014Assignee: Seiko Epson CorporationInventors: Maho Terashima, Naoki Gobara
-
Patent number: 8634510Abstract: A bang-bang frequency detector with no data pattern dependency is provided. In examples, the detector recovers a clock from received data, such as data having a non-return to zero (NRZ) format. A first bang-bang phase detector (BBPD) provides first phase information about a phase difference between a sample clock and the clock embedded in the received data. A second BBPD provides second phase information about a second phase difference between the clock embedded in the received data and a delayed version of the sample clock. A frequency difference between the sample clock and the clock embedded in the received data is determined based on the first and second phase differences. The frequency difference can be used to adjust the frequency of the sample clock. A lock detector can be coupled to a BBPD output to determine if the sample clock is locked to the clock embedded in the received data.Type: GrantFiled: January 12, 2011Date of Patent: January 21, 2014Assignee: QUALCOMM IncorporatedInventors: Xiaohua Kong, Vannam Dang, Tirdad Sowlati
-
Patent number: 8634511Abstract: A digital phase frequency detector includes a detection unit, a reset unit and a phase comparison unit. The detection unit detects edges of a reference signal and a feedback input signal to generate a reference edge signal and a feedback edge signal. The reset unit generates a reset signal resetting the detection unit based upon the reference edge signal and the feedback edge signal. The phase comparison unit generates first and second phase comparison signals based upon the reference edge signal and the feedback edge signal. The phase comparison unit includes a first flip-flop generating a first comparison signal based upon the reference edge signal and the feedback edge signal, a second flip-flop generating a second comparison signal based upon the reference edge signal and the feedback edge signal, and a latch block latching the first and second comparison signals to generate the first and second phase comparison signals.Type: GrantFiled: December 9, 2011Date of Patent: January 21, 2014Assignee: Samsung Electronics Co., Ltd.Inventors: Jong-Phil Hong, Ji-Hyun Kim, Jae-Jin Park
-
Patent number: 8634506Abstract: Generate a series of digital data according to a pair of differential signals received from a low speed universal serial bus. Calibrate coarsely a frequency of an oscillator according to a width of an end-of-packet of the series of digital data. And calibrate finely the frequency of the oscillator according to a width of a SYNC pattern of the series of digital data.Type: GrantFiled: October 20, 2010Date of Patent: January 21, 2014Assignee: Weltrend Semiconductor Inc.Inventors: Fu-Yuan Hsiao, Ke-Ning Pan
-
Patent number: 8630373Abstract: A receiver for receiving information that contains clock information and data information and a clock-embedded interface method. In the clock-embedded method, a clock signal and data may be reconstructed by receiving a pair of differential signals that contain clock information and data information and by using a change in a common voltage of the pair of differential signals.Type: GrantFiled: September 3, 2010Date of Patent: January 14, 2014Assignee: Samsung Electronics Co., Ltd.Inventors: Jae-hong Ko, Paul Kim
-
Publication number: 20140010336Abstract: A variable delay circuit outputs a first delay signal obtained by variably adding a delay value to a first signal having a predetermined phase. A mixer receives the first delay signal and a second signal having a phase different from the predetermined phase, and outputs a synthesized signal of the first delay signal and the second signal. A peak voltage detection unit detects the maximum value of an amplitude voltage of the synthesized signal output from the mixer. A comparator controls the delay value added by the variable delay circuit to match the maximum value detected by the peak voltage detection unit and a predetermined voltage.Type: ApplicationFiled: September 10, 2013Publication date: January 9, 2014Applicant: FUJITSU LIMITEDInventor: Kouichi SUZUKI
-
Patent number: 8625730Abstract: In a phase locked loop, frequency-divided clocks each of which is given a phase difference of at least one cycle of a feedback clock are inputted to a first phase comparator and a second phase comparator, respectively, which are made to perform phase comparison with a reference clock. Then, outputs of the first and second phase comparators are weighted by a result of the phase comparison of a receive signal and the feedback clock, and phase adjustment of the feedback clock is phase adjusted using the weighted outputs. Thereby, it is possible to lower a frequency of the reference clock and consequently to suppress power consumption.Type: GrantFiled: July 12, 2011Date of Patent: January 7, 2014Assignee: Hitachi, Ltd.Inventors: Tatsunori Usugi, Daisuke Hamano
-
Publication number: 20140003555Abstract: A phase excursion compensation circuit of a phase modulation signal demodulator detects occurrence of a slip of a received signal from a change in a phase compensation amount that is formed into the received signal by a phase excursion compensation unit, and corrects the phase compensation amount of the received signal after the slip is generated.Type: ApplicationFiled: November 15, 2011Publication date: January 2, 2014Applicant: NEC CorporationInventors: Masahiro Shigihara, Kiyoshi Fukuchi
-
Patent number: 8619934Abstract: A clock data recovery system is described. It includes a high pass filter for transmitting a filtered data signal in response to receiving an input data signal; an adder for summing the filtered data signal with a feedback signal, wherein the adder produces a summed input signal; a plurality of clocked data comparators for receiving the summed input signal, wherein the clocked data comparators determine an input data bit value; a plurality of clocked error comparators for receiving an error signal associated with clock recovery; an equalization and adaptation logic for selecting an error sample such that a phase associated with the error sample is locked at a second post cursor; and a phase mixer for transmitting a delay in response to receiving the phase and the delay is transmitted to the clocked-data comparators and the clocked-error comparators.Type: GrantFiled: August 11, 2010Date of Patent: December 31, 2013Assignee: Texas Instruments IncorporatedInventors: Hae-Chang Lee, Arnold Robert Feldman, Andrew Joy
-
Patent number: 8618967Abstract: Systems, methods, and circuits provide a time to digital converter comprising a sigma-delta modulator. The sigma-delta based time to digital converter may receive an analog signal representing a phase error between a reference clock signal and a feedback clock signal and generate a digital signal representing the phase error. The sigma-delta modulator may comprise a subtractor, an integrator, a feedback path, and a quantizer. The subtractor may receive the analog signal and subtract a feedback signal from the analog signal and the integrator may integrate the output of the subtractor. The sigma-delta modulator may accumulate a voltage or a charge over a capacitor as pulses are received from the analog signal and after a number of clock cycles, the capacitor may be discharged to generate a pulse in an output signal.Type: GrantFiled: March 30, 2012Date of Patent: December 31, 2013Assignee: Broadcom CorporationInventors: Parastoo Nikaeen, Stefanos Sidiropoulos, Marc Joseph Loinaz
-
Patent number: 8619935Abstract: Methods and structure for on-chip self-test of clock jitter for an application clock signal generated within an integrated circuit (IC). Features and aspects hereof provide for acquisition of samples of an application clock signal within the IC and counting the number of samples having a predetermined value. The count is compared to acceptable limits range values to generate a pass/fail signal of the IC use by external automated. A sample clock is generated based on the reference clock used by a Phase Locked Loop (PLL) circuit. An incremental delay is added to the sample clock pulse such that the sequence of samples “walk” through an application clock pulse waveform to sense clock jitter at various points of the waveform based on the counts. Acceptable limits range for the count at each sampled point, the incremental delay, and the number of samples at each delayed value may be user programmed.Type: GrantFiled: October 26, 2010Date of Patent: December 31, 2013Assignee: LSI CorporationInventors: Douglas J. Feist, Tracy J. Feist
-
Patent number: 8619936Abstract: A radio system having multi-standard mixed mode radios is described. The mixed mode radios are used to support combining of digital baseband from a first and a second radio equipment controller. A primary clock associated with the first radio equipment controller and a secondary clock associated with the second radio equipment controller is provided. The quality of the primary clock is evaluated and the primary clock is referenced to the first radio equipment controller if the clock is determined to have appropriate quality factors. The quality of the secondary clock is then evaluated and the secondary clock is referenced to the second radio equipment controller if the secondary clock is determined to have appropriate quality factors. The second radio equipment controller is then referenced to the primary clock once the primary and secondary clocks are aligned.Type: GrantFiled: April 11, 2012Date of Patent: December 31, 2013Assignee: Telefonaktiebolaget L M Ericsson (publ)Inventors: Beata Mirek, Glen Rempel, Keith Dysart
-
Patent number: 8619758Abstract: The present invention includes a network telephone having a microphone coupled to provide voice data to a network, a speaker coupled to facilitate listening to voice data from the network, a dialing device coupled to facilitate routing of voice data upon the network, a first port configured to facilitate communication with a first network device, a second port configured to facilitate communication with a second network device and a prioritization circuit coupled to apply prioritization to voice data provided by the microphone.Type: GrantFiled: March 25, 2011Date of Patent: December 31, 2013Assignee: Broadcom CorporationInventors: Theodore F. Rabenko, Ian Crayford, David L. Hartman, Jr.
-
Patent number: 8619933Abstract: Data received by a receiver is processed at a sampling rate indicated manually or automatically in the receiver. The sampling rate of the received data is controlled in accordance with the processing rate. The sampling rate controlled data is then processed so as to convert its frequency distribution to that the received data originally had.Type: GrantFiled: February 16, 2010Date of Patent: December 31, 2013Assignee: Oki Electric Industry Co., Ltd.Inventor: Hiromi Aoyagi
-
Patent number: 8615063Abstract: A level transition determination circuit includes a multi-phase clock generator, an oversampling unit, and a state detection circuit. The multi-phase clock generator is used for receiving an input clock signal and generating S×N clock signals, in which S and N are integers. Each clock signal is synchronized to the input clock signal and has a different delay time. The oversampling unit is used for performing N-times oversampling on M bit periods of the serial input data according to the clock signals, so as to generate M×N sampled values in parallel during the M bit periods. The state detection circuit is used for receiving (M×N)+1 sampled values and generating N detection signals by detecting level transitions between adjacent sampled values of the (M×N)+1 sampled values and the level transition results.Type: GrantFiled: July 27, 2011Date of Patent: December 24, 2013Assignee: Industrial Technology Research InstituteInventors: Jung Mao Lin, Ching Yuan Yang
-
Patent number: 8611486Abstract: Embodiments of the invention are generally directed to adjustment of clock signals regenerated from a data stream. An embodiment of a method includes receiving a data stream from a transmitting device via a communication link, the data stream including stream data, a link clock signal, and timestamps to indicate a relationship between the link clock signal and a stream clock signal. The method further includes adjusting the stream clock based at least in part on one or more measurements related to the data stream, the one or more measurements including a count of a number of pulses of the stream clock during a period of time, or a measurement of a number of data elements from the data stream stored in a buffer at a certain point in time.Type: GrantFiled: April 8, 2011Date of Patent: December 17, 2013Assignee: Silicon Image, Inc.Inventors: Hoon Choi, Daekyeung Kim, Ju Hwan Yi, Young Don Bae
-
Patent number: 8611487Abstract: One embodiment of the present invention relates to a phase alignment system including a plurality of samplers, a clock distributor, a phase detector and a phase alignment control. The samplers are configured to receive an incoming signal and a phase adjusted clock signal and to provide samples according to the incoming signal. The clock distributor receives a clock adjustment signal and generates the phase adjusted clock signal, which triggers sampling of the incoming signal. The clock adjustment signal indicates a direction of phase adjustment and can include an amount of phase adjustment. The phase detector receives the samples and provides extended phase alignment commands derived from the samples. The phase alignment control receives the extended phase alignment commands and provides the clock adjustment signal to the clock distributor.Type: GrantFiled: June 30, 2011Date of Patent: December 17, 2013Assignee: Intel Mobile Communications GmbHInventor: Holger Wenske
-
Patent number: 8611451Abstract: A method of operation in a receive circuit is disclosed. The method comprises entering an initialization mode followed by receiving training data from a lossy signaling path. The training data originates from a transmit circuit. The received training data is sampled and minimax transmit equalizer coefficients are generated based on the sampled data. The minimax transmit equalizer coefficients are then transmitted back to the transmit circuit. The initialization mode is exited and an operating mode initiated, where transmit data precoded by the minimax transmit equalizer coefficients is received.Type: GrantFiled: February 29, 2012Date of Patent: December 17, 2013Assignee: Aquantia CorporationInventor: Hossein Sedarat
-
Patent number: 8605848Abstract: An arrangement for synchronizing a transmission time of a digital data stream in individual high-frequency transmitters of a common-wave network operating according to an ATSC standard and transmitting identical data at an identical frequency. The stream generated in a master station is supplied to the transmitters as a periodic succession of data frames, and a setpoint transmission time is calculated in the transmitters from a synchronizing time stamp inserted into the data frames within the master station and from a time reference used in the master station and transmitters, while the transmission of the frames by the transmitter is determined by a system clock in the transmitters. The setpoint transmission time is compared with the actual transmission time determined by the clock, and the clock frequency is regulated by a regulating circuit so that the actual transmission time determined by the clock corresponds with the calculated setpoint transmission time.Type: GrantFiled: March 9, 2007Date of Patent: December 10, 2013Assignee: Rohde & Schwarz GmbH & Co. KGInventors: Cornelius Heinemann, Wolfgang Boehm
-
Patent number: 8605825Abstract: Provided is a receiving apparatus that receives a data signal and a clock signal indicating a reference timing to acquire the data signal. The receiving apparatus includes a multi-strobe generating section that generates, based on a pulse of the recovered clock, a plurality of strobes of which phases are different from each other, a first detecting section that detects a position of an edge of the clock signal relative to the strobes based on values of the clock signal that are acquired at respective timings of the strobe, a first adjusting section that adjusts a phase of the recovered clock according to the edge position of the clock signal, and a second adjusting section that adjusts the timing to acquire the data signal according to a phase adjustment amount of the recovered clock made by the first adjusting section.Type: GrantFiled: July 27, 2011Date of Patent: December 10, 2013Assignee: Advantest CorporationInventor: Nobuei Washizu
-
Patent number: 8605850Abstract: A method and system of providing a phase reference signal includes generating a reference signal having a reference frequency, modulating the reference signal at a modulation frequency lower than the reference frequency to obtain a modulated drive signal, receiving the modulated drive signal at a phase reference, and generating the phase reference signal based on the modulated drive signal. The phase reference signal including multiple reference tones having corresponding tone frequencies clustered around multiples of the reference frequency. A spacing between adjacent tones of the multiple reference tones is the same as the modulation frequency or an integer multiple of the modulation frequency.Type: GrantFiled: March 25, 2011Date of Patent: December 10, 2013Assignee: Agilent Technologies, Inc.Inventors: Keith F. Anderson, Loren C. Betts
-
Patent number: 8605846Abstract: Various embodiments of the present invention relate to systems, devices and methods of oversampling electronic components where high frequency oversampling clock signals are generated internally. The generated oversampling clock is automatically synchronous with the input clock and the input serial data in a serial data link, and is adaptive to predetermined parameters, such as bit depth and oversampling rate.Type: GrantFiled: December 17, 2010Date of Patent: December 10, 2013Assignee: Maxim Integrated Products, Inc.Inventors: Matthew Felder, Mark Summers
-
Patent number: 8605849Abstract: A clock and data recovery (CDR) circuit includes an edge detector, an edge selector, and a phase selector. The edge detector is arranged to detect edges of serial input data and to provide an edge detection result. The serial input data is oversampled utilizing multiple clock phases. The edge selector for selecting one of the multiple clock phases for a recovered clock is arranged to provide an edge selection result, to receive the last edge selection result as a first input, and to receive the edge detection result as a second input. The phase selector is arranged to provide the recovered clock and recovered data.Type: GrantFiled: October 15, 2010Date of Patent: December 10, 2013Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.Inventor: Yu-Chi Chen
-
Patent number: 8605847Abstract: In described embodiments, a transceiver includes a clock and data recovery module (CDR) with an eye monitor and a cycle slip monitor. The cycle slip detector monitors a CDR lock condition, which might be through detection of slips in sampling and/or transition timing detection. The cycle slip detector provides a check point to sense system divergence, allowing for a mechanism to recover CDR lock. In addition, when the CDR is out-of-lock, the various parameters that are adaptively set (e.g., equalizer parameters) might be invalid during system divergence. Consequently, these parameters might be declared invalid by the system and not used.Type: GrantFiled: March 9, 2011Date of Patent: December 10, 2013Assignee: LSI CorporationInventors: Mohammad Mobin, Mark Trafford, Ye Liu, Vladimir Sindalovsky, Amaresh Malipatil
-
Patent number: 8599985Abstract: In accordance with an embodiment of the present disclosure a phase-locked loop comprises a voltage controlled oscillator (VCO) configured to generate an output signal based on an input reference signal. The phase-locked loop further comprises a first charge pump communicatively coupled to a control input of the VCO and configured to generate, for a duration of time following occurrence of an event, a first control signal. The first control signal is independent of the output signal and is for causing the output signal to have a first frequency based on a second frequency of the input reference signal. The phase-locked loop further comprises a second charge pump communicatively coupled to the control input of the VCO. The second charge pump is configured to generate, after the duration of time, a second control signal.Type: GrantFiled: April 5, 2011Date of Patent: December 3, 2013Assignee: Intel IP CorporationInventor: Rizwan Ahmed
-
Patent number: 8598910Abstract: In described embodiments, a timestamp generator includes a fixed clock domain driven by a fixed frequency clock, a core clock domain, coupled to the fixed clock domain, which is driven by a core clock whose frequency is adjustable during an operation of the timestamp generator. A timestamp logic operating in the core clock domain generates a timestamping output of the timestamp generator. A rate generator operating in both the fixed clock domain and the core clock domain generates per clock cycle increments in the fixed clock domain and transfers carry units from the fixed clock domain into the core clock domain, and a timestamp increment generation of the timestamp logic is clocked by the fixed frequency clock provided by the rate generator. A method for enabling timestamp in an ASIC to be accurate with system clock changes is also described.Type: GrantFiled: August 2, 2012Date of Patent: December 3, 2013Assignee: LSI CorporationInventors: John Leshchuk, Joseph A. Manzella, Walter A. Roper
-
Patent number: 8599984Abstract: A delay locked loop operates over a wide range of frequencies and has high accuracy, small silicon area usage, low power consumption and a short lock time. The DLL combines an analog domain and a digital domain. The digital domain is responsible for initial lock and operational point stability and is frozen after the lock is reached. The analog domain is responsible for normal operation after lock is reached and provides high accuracy using smaller silicon area and low power.Type: GrantFiled: March 26, 2013Date of Patent: December 3, 2013Assignee: MOSAID Technologies IncorporatedInventors: Peter Vlasenko, Dieter Haerle
-
Patent number: 8594168Abstract: As a digitized representation of an intermediate frequency television signal moves through a demodulator it undergoes a number of processes, including conversion from an analog signal to a digitized data, digital signal processing of the digitized data, and the like. The rate at which the digitized data moves through the digital signal processor of the demodulator for processing is referred to as the data rate of the DSP. The demodulator can vary the data rate based on a selected television channel, thereby reducing the level of interference at the demodulator resulting from noise.Type: GrantFiled: February 29, 2012Date of Patent: November 26, 2013Inventors: Gary Cheng, Vyacheslav Shyshkin, Steve Selby
-
Patent number: 8595543Abstract: A circuit and method for trimming an internal oscillator of a USB device that generates a clock signal as a frequency source of the USB device detect an end of packet from an input data stream to initialize a counter, identify a token packet in the data stream to detect a start of frame token packet for the counter to carry out clock counting on the clock signal to thereby obtain a count value, and compare the count value with a reference value to determine a trimming code for trimming a clock frequency of the internal oscillator.Type: GrantFiled: September 24, 2010Date of Patent: November 26, 2013Assignee: Elan Microelectronics CorporationInventors: Tsung-Yin Chiang, Chun-Chi Wang, Po-Hao Wu, Chun-An Tang
-
Patent number: 8594264Abstract: Alignment of a clock signal to a particular phase is described. In one aspect, a method includes receiving an incoming clock signal and multiple phased clock signals, each of the phased clock signals having a different phase and a substantially same phase offset from another phased clock signal. At least one detection signal based on the incoming and phased clock signals is provided, and one or more errors contributed by noise in at least the incoming clock signal are corrected in the at least one detection signal. Based on the at least one detection signal, one of the phased clock signals is selected as the most closely aligned of the phased clock signals to the predetermined clock phase, and the selected clock signal is output.Type: GrantFiled: December 14, 2010Date of Patent: November 26, 2013Assignee: Xilinx, Inc.Inventors: Xiang Zhu, Greg W. Starr
-
Patent number: 8588358Abstract: A clock and data recovery (CDR) circuit includes an inductor-capacitor voltage controlled oscillator (LCVCO) configured to generate a clock signal with a clock frequency. A delay locked loop (DLL) is configured to receive the clock signal from the LCVCO and generate multiple clock phases. A charge pump is configured to control the LCVCO. A phase detector is configured to receive a data input and the multiple clock phases from the DLL, and to control the first charge pump in order to align a data edge of the data input and the multiple clock phases.Type: GrantFiled: March 11, 2011Date of Patent: November 19, 2013Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.Inventors: Chan-Hong Chern, Chih-Chang Lin, Ming-Chieh Huang, Fu-Lung Hsueh
-
Patent number: 8588356Abstract: A method for receiving a signal having a succession of symbols, transmitted by a digital modulation, each symbol transmitted having a phase and an amplitude belonging to a set of values in finite number, the method includes evaluating a phase error (PHE) on a received symbol (S), resulting from a signal transmission noise, correcting the phase of the received symbol according to the phase error evaluated, demodulating the symbol corrected in phase, and modeling the transmission noise by a Gaussian component not correlated with the signal received and defined by a power and an interference component defined by an amplitude and which phase is substantially uniformly distributed, the phase error of the received symbol evaluated on the basis of the power of Gaussian component and the amplitude of the interference component.Type: GrantFiled: October 21, 2010Date of Patent: November 19, 2013Assignee: STMicroelectronics (Grenoble 2) SASInventor: Jacques Meyer
-
Patent number: 8587337Abstract: An embodiment of a technique to capture and locally synchronize data is disclosed. The technique includes receiving first and second signals through a first interface, and receiving a third signal through a second interface where the third signal is unsynchronized with respect to the second signal. The technique further includes detecting a first phase difference between the second and third signals, and generating a fourth signal in a manner so that a second phase difference between the fourth signal and one of the second or third signals is a function of the first phase difference. In addition, the technique includes storing a state of the first signal in response to the fourth signal, and thereafter supplying the stored state of the first signal to the second interface.Type: GrantFiled: January 19, 2010Date of Patent: November 19, 2013Assignee: Xilinx, Inc.Inventors: Schuyler E. Shimanek, Adam Elkins, Wayne E. Wennekamp
-
Patent number: 8588355Abstract: A timing recovery controller capable of performing timing recovery for a data sequence at twice a symbol rate includes a sampler, a timing base device, a timing error detector and a timing lock detector. The timing error detector includes a first delay unit and a second delay unit, for delaying a data sequence to output a first delay data sequence and a second delay data sequence, respectively, and a timing error calculating module, for generating a timing error value, to adjust a time base. The timing lock detector includes a third delay unit, for delaying the data sequence to output a third delay data sequence, and a timing lock determination module, for generating a timing lock determination result.Type: GrantFiled: August 6, 2010Date of Patent: November 19, 2013Assignee: NOVATEK Microelectronics Corp.Inventor: Kung-Piao Huang
-
Patent number: 8588357Abstract: A phase selector capable of tolerating jitters is applied in a clock and data recovery circuit. The phase selector includes a comparing module, a weighting circuit, and a predictor. The comparing module compares a phase-detecting signal and a phase-selecting signal corresponding to the last cycle so as to generate an error signal. The weighting circuit calculates a weighting error signal according to the error signal and a weighting parameter. The phase predictor compares the weighting error signal and predetermined threshold values so as to generate the phase-selecting signal corresponding to the present cycle. When the received input data stream of the clock and data recovery circuit has a small jitter, the phase selector rapidly locks the phase so as to generate the correct phase-selecting signal. When the received input data stream of the clock and data recovery circuit has a large jitter, the phase selector stably generates the phase-selecting signal.Type: GrantFiled: October 27, 2011Date of Patent: November 19, 2013Assignee: Etron Technology, Inc.Inventors: Kuo-Cyuan Kuo, Huei-Chiang Shiu, Hsieh-Huan Yen
-
Patent number: 8582710Abstract: Embodiments allow for the use of the SS modulation technique (and thus for significant reduction of EMI due to clock transmission) in scenarios involving tight synchronization requirements between two devices. In particular, embodiments can be used in high-speed communication networks (e.g., high-speed Ethernet) where a clock signal embedded in the data stream at the transmitter and recovered from the data stream at the receiver is the only source for synchronization between the transmitter and the receiver (i.e., no other synchronization channel available). Embodiments are also especially useful in communication systems utilizing echo cancellers.Type: GrantFiled: March 31, 2011Date of Patent: November 12, 2013Assignee: Broadcom CorporationInventors: Neven Pischl, Joseph Cordaro, Yongbum Kim
-
Patent number: 8582708Abstract: A clock and data recovery circuit includes a multiphase clock generator circuit which generates a multiphase clock having a plurality of clocks, a sampling circuit which samples a received data signal transferring serial data in synchronism with each of the plurality of clocks, and generates a plurality of data signals, a data recovery unit which generates a selection signal indicating a data signal having an appropriate phase among the plurality of data signals, and a storage unit which stores the selection signal. The data recovery unit selects one of the plurality of data signals, based on the selection signal read from the storage unit, and a clock corresponding to the selected data signal.Type: GrantFiled: January 5, 2012Date of Patent: November 12, 2013Assignee: Panasonic CorporationInventors: Michiyo Yamamoto, Kenji Murata, Kazuya Hatooka
-
Publication number: 20130294555Abstract: The present invention discloses a method and apparatus for addressing the issue of clock skew in a data signal while making efficient use of space on an integrated chip (IC) by utilising a physical delay line controlled by a state machine in conjunction with pre-requisite chip architecture. The pre-requisite chip architecture samples the incoming data signal in response to a clocking signal input from the physical delay line; the physical delay line responds to commands from the state machine to increment the delay of the physical delay line to produce samples which describe the incoming data signal and delineate its data valid window.Type: ApplicationFiled: July 1, 2013Publication date: November 7, 2013Inventors: Wally Haas, Mutema John Pittman
-
Publication number: 20130294492Abstract: A system may include a clock and data recovery circuit that includes one or more analog components. The system may also include a digital control circuit configured to control the clock and data recovery circuit. The digital control circuit and the clock and data recovery circuit may be formed on a single substrate.Type: ApplicationFiled: May 4, 2012Publication date: November 7, 2013Applicant: FINISAR CORPORATIONInventor: Jason Y. MIAO
-
Patent number: 8576967Abstract: It is possible to provide a highly reliable semiconductor device and a communication method in which communication can be performed between circuits with a large degree of freedom of clock frequency which can be set in each of the circuits, a decisive operation, and a small communication latency. The semiconductor device according to the present invention includes a first circuit that performs processing based on a first clock signal, the first clock signal having a frequency M/N times as large as a frequency of a second clock signal (N is a positive integer, and M is a positive integer larger than N); a second circuit that performs processing based on the second clock signal; and a communication timing control circuit that generates a communication timing signal to control a timing at which the first circuit performs communication with the second circuit.Type: GrantFiled: April 14, 2009Date of Patent: November 5, 2013Assignee: NEC CorporationInventor: Atsufumi Shibayama
-
Patent number: 8576961Abstract: A method for determining an overlap and add length estimate comprises determining a plurality of correlation values of a plurality of ordered frequency domain samples obtained from a data frame; comparing the correlation values of a first subset of the samples to a first predetermined threshold to determine a first edge sample; comparing the correlation values of a second subset of the samples to a second predetermined threshold to determine a second edge sample; using the first and second edge samples to determine an overlap and add length estimate; and providing the overlap and add length estimate to an overlap and add circuit.Type: GrantFiled: June 15, 2009Date of Patent: November 5, 2013Assignee: Olympus CorporationInventors: Haidong Zhu, Dumitru Mihai Ionescu, Abu Amanullah
-
Patent number: 8576970Abstract: A PLL circuit (1a, 1b) for generating a pixel-clock signal based on a hsync signal. The PLL circuit comprises a phase-frequency detector arranged to receive the hsync signal and a frequency divided pixel-clock signal, and generate up and down signals based on the hsync signal and the frequency-divided pixel-clock signal. A charge pump (20) is arranged to generate an output signal based on the up and down signals and a loop filter (30) is arranged to generate a frequency-control signal based on the output signal of the charge pump (20). Furthermore, a VCO (40a, 40b) is arranged to generate an oscillating signal and adjust the frequency of the oscillating signal in response to the frequency-control signal. The VCO (40a, 40b) is adapted to have a tuning range with a center frequency which is larger than or equal to 4 GHz.Type: GrantFiled: September 9, 2009Date of Patent: November 5, 2013Assignee: CSR Technology Inc.Inventors: Graham R. Leach, Gordon A. Wilson, Rolf Sundblad
-
Patent number: 8576952Abstract: A configurable all-digital coherent demodulator system for spread spectrum digital communications is disclosed herein. The demodulator system includes an extended and long code demodulator (ELCD) coupled to a traffic channel demodulator (TCD) and a parameter estimator (PE). The demodulator also includes a pilot assisted correction device (PACD) that is coupled to the PE and the TCD. The ELCD provides a code-demodulated signal to the TCD and the PE. In turn, the TCD provides a demodulated output data signal to the PE. The PACD corrects the phase error of the demodulated output data based on an error estimate that is fed forward from the PE. Accumulation operations in the ELCD, TCD, and PE are all programmable. Similarly, a phase delay in the PACD is also programmable to provide synchronization with the error estimate from the PE.Type: GrantFiled: May 1, 2012Date of Patent: November 5, 2013Assignee: Intel Mobile Communications GmbHInventor: Ravi Subramanian
-
Patent number: 8571150Abstract: According to one embodiment, a frequency offset compensation apparatus includes a first estimation unit, a second estimation unit, a setting unit, a synthesis unit and a compensation unit. The first estimation unit estimates a first rotation. The second estimation unit estimates a second rotation. The setting unit sets a weighting factor for the second rotation to a first value if a received power is less than a threshold value, and sets the weighting factor for the rotation to a second value being smaller than the first value if the received power is not less than the threshold value. The synthesis unit calculates a compensation value. The compensation unit compensates for a frequency offset.Type: GrantFiled: March 1, 2012Date of Patent: October 29, 2013Assignee: Kabushiki Kaisha ToshibaInventors: Seiichiro Horikawa, Koichiro Ban
-
Patent number: 8571160Abstract: For estimating a difference between a frequency of a base station and a locally generated frequency of a mobile equipment in a mobile communications network, wherein at least a signal in a plurality of signals transmitted from the base station and received by the mobile equipment comprises a plurality of symbols each of which includes a cyclic prefix, a correlation between a symbol and its cyclic prefix is used for estimating the frequency difference.Type: GrantFiled: August 1, 2008Date of Patent: October 29, 2013Assignee: Nokia CorporationInventor: Teemu Taneli Sipila
-
Patent number: 8571161Abstract: It is described an electronic device for generating a fractional synthesized frequency. The device comprises a multi-phase controlled oscillator configured to generate, from a control signal, a plurality of signals phase-shifted each other and comprises a phase detector configured to receive a selected signal from the plurality of phase-shifted signals, to receive a reference signal and to measure a difference between a phase of the selected signal and a phase of the reference signal. The electronic device further comprises control means for estimating, from the measured phase difference, a phase error affecting the generation of at least one of the plurality of phase-shifted signals, and for generating a corrected measure of the phase difference taking into account the estimated phase error, the corrected measure being used to provide the control signal.Type: GrantFiled: February 3, 2010Date of Patent: October 29, 2013Assignee: Politechnico di MilanoInventors: Salvatore Levantino, Carlo Samori, Marco Zanuso