By Filtering (e.g., Digital) Patents (Class 375/350)
  • Patent number: 8693581
    Abstract: Disclosed is a method for receiving an analog signal from a receiver supporting at least a first channel band and a second channel band. The method for receiving an analog signal includes sampling the analog signal received through an antenna, generating a decimated signal by passing the sampled signal to a CIC decimation filter; and inputting the decimated signal to a channel selection filter.
    Type: Grant
    Filed: October 28, 2011
    Date of Patent: April 8, 2014
    Assignee: Electronics & Telecommunications Research Institute
    Inventors: Sang-Kyun Kim, Ik Soo Eo, Mijeong Park, Hyun Kyu Yu
  • Patent number: 8693972
    Abstract: A method and system is disclosed for designing a radio for down-converting RF signals to IF signals by sampling the signals in a round-robin sampling circuit and multiplying the samples by coefficients that are changed at a fixed rate equal to the rate of operation of each of the sampling circuits. The circuit is able to down-convert multiple channels simultaneously to adjacent positions in the IF band, while rejecting unwanted image signals. The method and system avoids the difficulty and cost of directly digitizing the RF signal, allowing each component to operate at a greatly reduced speed. The coefficients are selected to provide the desired transfer function while keeping the output signal centered at a desired frequency.
    Type: Grant
    Filed: November 3, 2012
    Date of Patent: April 8, 2014
    Assignee: ESS Technology, Inc.
    Inventors: Dustin Dale Forman, A. Martin Mallinson, Robert Lynn Blair
  • Patent number: 8693602
    Abstract: Method and system for separating a plurality of users in a communication system including two transmitter antennas and N receiver antennas, said signals transmitted by said users containing symbols an, x( ) corresponding to the vector of the envelopes of the output signals of the 1 to N receiver antennas after a shaping filtering operation, characterized in that it uses a linear mean square filter extended over an observation vector {tilde over (x)}=[x(2n?1)T x(2n)T x(2n?1)H x(2n)H]T where x(2n?1) and x(2n) correspond to the (NĂ—1) (N?1) observations at the symbol times 2n?1 and 2n.
    Type: Grant
    Filed: November 3, 2010
    Date of Patent: April 8, 2014
    Assignee: Thales
    Inventors: Pascal Chevalier, Florian Dupuy
  • Patent number: 8693608
    Abstract: An endpoint or other communication device of a communication system includes a clock recovery loop having a phase error estimator. The communication device is operative as a slave device relative to another communication device that is operative as a master device. The clock recovery loop is configured to control a slave clock of the slave device responsive to a phase error estimate generated by the phase error estimator so as to synchronize the slave clock with a master clock of the master device. The phase error estimator comprises a plurality of filters each configured to generate a different estimate of master clock phase using at least a subset of a plurality of packets received from the master device, and control logic for adaptively selecting at least a particular one of the plurality of filters for use in generating the phase error estimate to be processed in the clock recovery loop.
    Type: Grant
    Filed: September 20, 2010
    Date of Patent: April 8, 2014
    Assignee: Alcatel Lucent
    Inventors: Ilija Hadzic, Dennis R. Morgan
  • Patent number: 8693562
    Abstract: A process receives a composite signal transmitted via a nonlinear data transmission channel, with the composite signal having a first signal UL and a second signal LL. The process includes the following: demodulating and decoding the first signal UL by using a first demodulation and decoding chain in order to regenerate first information of the first signal UL; recoding and shaping to produce a continuous time waveform; applying a nonlinearity function based on a set of coefficients updated according to an adaptive correlation calculation process to the continuous time waveform; subtracting the result of the nonlinearity function from the composite signal in order to generate a result E; and demodulating and decoding the result E by using a second demodulation and decoding chain in order to regenerate second information of the second signal LL.
    Type: Grant
    Filed: May 13, 2004
    Date of Patent: April 8, 2014
    Assignee: STMicroelectronics S.A.
    Inventor: Jacques Meyer
  • Patent number: 8693601
    Abstract: A system includes a polyphase multirate filter and a controller which, responsive to detecting a data stream: measures a current phase relationship between a current resampling filter input clock signal and a current multirate output clock signal; identifies, based on a mapping of the measured phase relationship within a pre-generated quantized mapping table, an initial polyphase filter coefficient index corresponding to the measured phase relationship; selects, based on the initial polyphase filter coefficient index identified, a corresponding polyphase filter component from within the multirate filter; configures the multirate filter to pass data from the data stream through the corresponding polyphase filter component to generate an initial output data sample; updates the initial polyphase filter coefficient index to a calculated next polyphase filter coefficient index value, in response to a request for generation of a next output data sample; and self-corrects the multirate filter responsive to a pre-ide
    Type: Grant
    Filed: January 3, 2012
    Date of Patent: April 8, 2014
    Assignee: Intel Corporation
    Inventors: Victor Adut, Gregory M. Agami, Yun H. Kim, Wei Chuan Ma
  • Patent number: 8687744
    Abstract: Aspects of a method and system for an improved cellular diversity receiver are described. Aspects of the system may include circuitry that enables generation of an initially decoded output bit sequence by a first frame process for a received bit sequence for a plurality of received multipath signals. The first frame process may utilize redundancy based decoding, which imposes at least one physical constraint during the decoding, which may be performed by a decoding algorithm.
    Type: Grant
    Filed: September 11, 2006
    Date of Patent: April 1, 2014
    Assignee: Broadcom Corporation
    Inventors: Arie Heiman, Nelson Sollenberger
  • Patent number: 8687682
    Abstract: A communication port and method of adapting a transmit filter in the port to reduce receive errors by a receiver coupled to the transmit filter via a communication channel. The filter has coefficients that are adjusted in response to a first adaptation gain value, decision bits, and receiver error values. During a first time period, the coefficients are adjusted until changes in the coefficients are less than a first threshold amount. Then during a second time period, the coefficients are adjusted using a second adaptation gain value until changes in the coefficients are less than a second threshold amount. The second adaptation gain value is less than the first adaptation gain value and the second threshold amount being less than the first threshold amount. By using two or more adjustment periods with different gain values, the filter is adapted faster than using a single adjustment period with fixed adaptation gain.
    Type: Grant
    Filed: January 30, 2012
    Date of Patent: April 1, 2014
    Assignee: LSI Corporation
    Inventors: Mohammad Mobin, Amaresh Malipatil, Adam Healey, Ye Liu
  • Patent number: 8687743
    Abstract: Methods and apparatus are provided for detecting and decoding adaptive equalization training frames (having a frame marker comprised of a string of binary ones and binary zeroes). Training frames are detected by shifting the received data; inserting at least one binary value at one end of the shifted received data to generate a modified version of the received data; applying a logic function to the received data and the modified version of the received data that identifies when corresponding bit positions have different values; and detecting the frame marker when an output of the logic function has a first binary value in an approximate middle of a string of a second binary value. The training frames are decoded using a distance between the approximate center of the frame marker and a predefined binary value in an output of the logic function.
    Type: Grant
    Filed: February 14, 2013
    Date of Patent: April 1, 2014
    Assignee: Agere Systems LLC
    Inventors: Yasser Ahmed, Xingdong Dai, Mohammad S. Mobin, Lane A. Smith
  • Publication number: 20140086374
    Abstract: A system and method for detecting broadband global positioning system (GPS) jamming is provided, the system including a local oscillator maintainer to maintain a plurality of local oscillators, a frequency band selector to select a frequency band in which jamming is to be detected, in response to receipt of a radio frequency (RF) signal, an oscillating signal output unit to allow an oscillating signal to be output from a local oscillator identified based on the selected frequency band, among the plurality of local oscillators, and an intermediate frequency (IF) signal generator to generate an IF signal using the RF signal and the oscillating signal.
    Type: Application
    Filed: September 11, 2013
    Publication date: March 27, 2014
    Applicant: Electronics and Telecommunications Research Institute
    Inventors: In One JOO, Jeom Hun LEE, Cheon Sig SIN, Sang Uk LEE
  • Patent number: 8681842
    Abstract: Systems and methods for measuring transmitter and/or receiver I/Q impairments are disclosed, including iterative methods for measuring transmitter I/Q impairments using shared local oscillators, iterative methods for measuring transmitter I/Q impairments using intentionally-offset local oscillators, and methods for measuring receiver I/Q impairments. Also disclosed are methods for computing I/Q impairments from a sampled complex signal, methods for computing DC properties of a signal path between the transmitter and receiver, and methods for transforming I/Q impairments through a linear system.
    Type: Grant
    Filed: April 9, 2012
    Date of Patent: March 25, 2014
    Assignee: National Instruments Corporation
    Inventor: Stephen L. Dark
  • Patent number: 8681890
    Abstract: A method of signal processing, or corresponding apparatus, includes providing multiple analog receive signals at respective antennas and selecting one antenna at a time in an iterative manner, to cycle through the antennas and provide a multiplexed analog signal. The multiplexed analog signal is filtered at a filter to pass a predetermined frequency band. The multiplexed analog signal is sampled at a single analog to digital converter to generate a multiplexed digital signal. The multiplexed digital signal is demultiplexed to generate multiple digital signals for digital processing. Sharing a receiver and ADC among multiple antennas results in reduced cost and power. Such cost and power reductions in turn enable larger antenna arrays than are available with prior art techniques, thereby promoting increased throughput and coverage.
    Type: Grant
    Filed: September 15, 2010
    Date of Patent: March 25, 2014
    Assignee: Entropic Communications, Inc.
    Inventor: Branislav Petrovic
  • Patent number: 8681598
    Abstract: A multiple-input multiple output (MIMO) receiver includes circuitry to receive a MIMO transmission through a plurality of antennas over a channel comprising two or more 20 MHz portions of bandwidth. The MIMO transmission comprises a plurality of streams, each transmitted over a corresponding spatial channel and configured for reception by multiple user stations. The MIMO receiver also includes circuitry to simultaneously accumulate signal information within at least two or more of the 20 MHz portions of bandwidth. Each 20 MHz portion comprises a plurality of OFDM subcarriers. The MIMO receiver also includes circuitry to demodulate at least one of the steams using receive beamforming techniques. In this way, multi-user protocol data units can be received.
    Type: Grant
    Filed: January 17, 2011
    Date of Patent: March 25, 2014
    Assignee: Intel Corporation
    Inventors: Alexander A. Maltsev, Ali S. Sadri, Sergey E. Sergeyev, Alexander N. Belonozhkin, Vadim S. Sergeyev
  • Patent number: 8681912
    Abstract: Method of estimating a channel in a wireless communication system by obtaining a channel impulse response from a pilot signal included in a received signal; estimating a timing offset with a maximum peak power value for the channel impulse response; and performing a phase compensation using the estimated timing offset and estimating a channel which is applied with the compensated phase.
    Type: Grant
    Filed: December 27, 2010
    Date of Patent: March 25, 2014
    Assignee: Samsung Electronics Co., Ltd
    Inventors: Hyo-Yol Park, Sung-Kwon Jo, Ha-Young Yang
  • Patent number: 8681850
    Abstract: A signal processing apparatus includes a signal processing unit configured to carry out signal processing on a single-carrier signal and a multi-carrier signal by making use of a plurality of common filters shared by the single-carrier signal and the multi-carrier signal.
    Type: Grant
    Filed: September 19, 2011
    Date of Patent: March 25, 2014
    Assignee: Sony Corporation
    Inventors: Hidetoshi Kawauchi, Naoki Yoshimochi, Kazukuni Takanohashi
  • Publication number: 20140079101
    Abstract: Aspects of a method and system for unconstrained frequency domain adaptive filtering include one or more circuits that are operable to select one or more time domain coefficients in a current filter partition. A value may be computed for each of the selected one or more time domain coefficients based on a corresponding plurality of frequency domain coefficients. The corresponding plurality of frequency domain coefficients may be adjusted based on the computed values. A subsequent plurality of frequency domain coefficients in a subsequent filter partition may be adjusted based on the computed values. Input signals may be processed in the current filter partition based on the adjusted corresponding plurality of frequency domain coefficients. A time-adjusted version of the input signals may be processed in a subsequent filter partition based on the adjusted subsequent plurality of frequency domain coefficients.
    Type: Application
    Filed: November 22, 2013
    Publication date: March 20, 2014
    Applicant: Broadcom Corporation
    Inventors: Kuoruey (Ray) Han, Peiqing Wang, Linghsiao Wang, Kishore Kota, Arash Farhoodfar
  • Publication number: 20140079167
    Abstract: Multi-function receivers are disclosed in which high dynamic range active microwave filters using nanoscale devices are disposed within a switched channelizer stage. In an embodiment the receiver includes an input low noise amplifier, a switched channelizer comprised of active filters utilizing nanoscale devices, an output amplifier, a mixer, and an analog to digital converter. Additionally, the use of highly selective active filters in the channelizer allows for the optional elimination of the mixing stage, improving cost and overall volume.
    Type: Application
    Filed: September 14, 2012
    Publication date: March 20, 2014
    Applicant: Northrop Grumman Systems Corporation
    Inventors: John D. Adam, Nicholas G. Paraskevopoulos
  • Publication number: 20140079168
    Abstract: A method and apparatus in which a Tap-Weight Computer (TWC) calculates a Tap-Weight Vector (TWV). The TWV is coupled to a register in each of a plurality of adaptive filter modules. Each such adaptive filter module includes several adaptive filters that each include a tapped delay line. The input to the tapped delay line of each such adaptive filter is one of a plurality of potential interfering signals. The TWV controls the weighting of the outputs from the taps off the delay line. The weighted outputs from each tapped delay line are then subtracted from a received signal which potentially includes interference from the potential interfering signals. The TWC is multiplexed to each of the plurality of adaptive filters so that each adaptive filter is loaded with a TWV calculated by the TWC to reduce the amount of interference contributed by a particular potential interfering signal coupled to an input to that particular adaptive filter.
    Type: Application
    Filed: November 18, 2013
    Publication date: March 20, 2014
    Applicant: Entropic Communications, Inc.
    Inventors: Branislav Petrovic, Michail Tsatsanis
  • Publication number: 20140079107
    Abstract: A system that incorporates teachings of the subject disclosure may include, for example, a method for identifying a spectral region in a radio frequency spectrum, determining a signal strength of the spectral region, determining a correlation factor by correlating the signal strength of the spectral region, identifying from the correlation factor interference in the spectral region, repeating a determination of the correlation factor and an identification of the interference until a desired confidence level has been achieved, and generating coefficient data to substantially suppress the interference in the channel responsive to achieving the desired confidence level. Other embodiments are disclosed.
    Type: Application
    Filed: September 14, 2012
    Publication date: March 20, 2014
    Applicant: ISCO International, LLC
    Inventors: Amr Abdelmonem, Sean S. Cordone
  • Patent number: 8675791
    Abstract: The present invention relates to a method and apparatus for deconvolving a noisy measured signal obtained from a sensor device (100), said noisy measured signal (y(t)) being the sum of the convolution product (x(t)N(t)) of an input signal (x(t)) of the sensor device, representative of a feature of physical quantity, by a convolution kernel (N(t)) defined by the response function of the sensor device (100) and a noise which interfere with the measure. The method is characterized in that said method comprises an estimate computation step (400) in the course of which a minimal estimate (xmin(t)N(t)) of the convolution product of the input signal by the convolution kernel of the sensor device is computed in order that said minimal estimate stays below the noisy measured signal (y(t)) and has at least one point in common with the noisy measured signal (y(t)).
    Type: Grant
    Filed: January 9, 2009
    Date of Patent: March 18, 2014
    Assignee: Universite d'Angers
    Inventor: Christian Jeanguillaume
  • Patent number: 8676144
    Abstract: Interference in an unlicensed frequency band is spatially filtered out from received signals at a wireless device operating in the unlicensed frequency band. Energy received at a plurality of antennas of the wireless is device is analyzed to detect interference in the unlicensed frequency band. The detected interference is classified by type. Parameters for a nulling filter are generated or selected based on the type of interference detected in the received energy. During a time interval when it is expected to receive desired signals, the nulling filter is applied using the parameters to signals obtained from energy received at the plurality of antennas during the time interval.
    Type: Grant
    Filed: April 14, 2011
    Date of Patent: March 18, 2014
    Assignee: Cisco Technology, Inc.
    Inventors: Li Guo, Hang Jin, Paul J. Stager, Neil R. Diener, Matthew A. Silverman, Chandra Vaidyanathan
  • Patent number: 8675782
    Abstract: A receiver may be operable to receive a QAM-based, inter-symbol correlated (ISC) signal having pilot overhead of 5% at a signal-to-noise ratio (SNR). The receiver may be operable to process the QAM-based, ISC signal to output information at a particular rate with a symbol error rate lower than or equal to 1e?2. The first SNR may be at least 3 dB below a SNR required to achieve the same particular information rate and the same symbol error rate while processing a signal having zero inter-symbol interference.
    Type: Grant
    Filed: September 3, 2013
    Date of Patent: March 18, 2014
    Assignee: MagnaCom Ltd.
    Inventor: Amir Eliaz
  • Patent number: 8675796
    Abstract: A method for timing and frequency synchronization in a wireless system is provided. The method comprises the steps of receiving a burst of symbols, selecting a subset of the burst of symbols, iteratively adjusting the subset of the burst of symbols by a plurality of timing offsets and calculating, for each timing offset, a first performance metric corresponding to the adjusted subset. The method further comprises the steps of determining one of the plurality of timing offsets to be a preferred timing offset based upon the first performance metric thereof, iteratively rotating the subset of the burst of symbols by a plurality of frequency offsets and calculating, for each frequency offset, a second performance metric corresponding to the rotated subset, and determining one of the plurality of frequency offsets to be a preferred frequency offset based upon the second performance metric thereof.
    Type: Grant
    Filed: August 23, 2011
    Date of Patent: March 18, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Divaydeep Sikri, Farrokh Abrishamkar, Ming Yan, Nico De Laurentiis
  • Patent number: 8675717
    Abstract: In general, the subject matter described in this disclosure can be embodied in methods, systems, and program products for adapting data rate. The method includes receiving a data transmission at a data rate, identifying a first quantity of packets that were not adequately received, and using the first quantity to increase a packet loss level. A second quantity of improper bits in those packets that were adequately received at the data rate are identified, and the second quantity is used to increase a bit error level. As a result of having determined that the first value does not satisfy a first criterion for reducing the rate of the data transmission and that the second value does satisfy a second criterion for increasing the rate of the data transmission, an instruction is sent for causing the sending device to increase the rate of the data transmission.
    Type: Grant
    Filed: October 16, 2012
    Date of Patent: March 18, 2014
    Assignee: Google Inc.
    Inventors: Yuan Yuan, C. Philip Gossett
  • Patent number: 8675792
    Abstract: A method includes receiving a signal comprising a symbol-carrier matrix, the symbol-carrier matrix including a predetermined pattern of reference symbols, and determining at least one channel estimate ?i,k at at least one of the reference symbol positions of the reference symbols in the symbol-carrier matrix, wherein i=0,1,2, . . . is the carrier index and k=0,1,2, . . . is the symbol index of the symbol-carrier matrix. The method further includes determining a Doppler spread {circumflex over (?)}D on the basis of the at least one channel estimate ?i,k.
    Type: Grant
    Filed: September 7, 2011
    Date of Patent: March 18, 2014
    Assignee: Intel Mobile Communications GmbH
    Inventors: Cecilia Carbonelli, Michael Horvat
  • Patent number: 8670733
    Abstract: A multimode communication device with a shared signal path programmable filter and a method for utilizing a shared signal path programmable filter in a multimode communication device. Various aspects of the present invention comprise a first module adapted to receive a first communication signal (e.g., corresponding to a first communication protocol) and a second module adapted to receive a second communication signal (e.g., corresponding to a second communication protocol). A shared filter, communicatively coupled to the first and second modules, may be adapted to filter the first and/or second communication signals in accordance with a plurality of selectable sets of filter response characteristics (e.g., associated with the first and second communication protocols). A filter control module may be adapted to select a set of filter response characteristics from a plurality of such sets and program the shared filter to filter a communication signal in accordance with the selected set.
    Type: Grant
    Filed: January 23, 2012
    Date of Patent: March 11, 2014
    Assignee: Broadcom Corporation
    Inventors: Arya Behzad, Ahmadreza Rofougaran
  • Patent number: 8670739
    Abstract: A high quality factor frequency translated bandpass filter (FTBPF) with harmonic rejection includes multiple transconductance cells configured to convert a received radio frequency (RF) voltage signal into respective RF current signals. Each of the transconductance cells are weighted such that the FTBPF has an effective transconductance of a first magnitude for frequency components of the received RF voltage signal arising from a first harmonic and an effective transconductance of a second magnitude less than the first magnitude for frequency components of the received RF voltage signal arising from harmonics at integer multiples of the first harmonic. The FTBPF also includes multiple frequency conversion cells coupled to the transconductance cells and configured to mix respective ones of the RF current signals with multiple non-overlapping local oscillator signals.
    Type: Grant
    Filed: January 8, 2013
    Date of Patent: March 11, 2014
    Assignee: Broadcom Corporation
    Inventors: David Murphy, Hooman Darabi
  • Patent number: 8670506
    Abstract: An apparatus according to an embodiment of the present invention for providing a reduced representation in a frequency-domain, based on a time-based RF signal, has a time-frequency converter adapted to transform the time-domain RF signal to obtain a frequency-domain representation based on the time-domain signal and an entropy encoder adapted to obtain the reduced representation based on the frequency-domain representation by entropy encoding.
    Type: Grant
    Filed: February 10, 2012
    Date of Patent: March 11, 2014
    Assignee: Innovationszentrum fuer Telekommunikationstechnik GmbH IZT
    Inventors: Rainer Perthold, Dieter Weninger
  • Patent number: 8670494
    Abstract: The present invention relates to method of transmitting and receiving signals and a corresponding apparatus. One aspect of the present invention relates to an efficient layer 1 (L1) processing method for a transmitter and a receiver using data slices.
    Type: Grant
    Filed: May 13, 2009
    Date of Patent: March 11, 2014
    Assignee: LG Electronics Inc.
    Inventors: Woo Suk Ko, Sang Chul Moon
  • Patent number: 8670507
    Abstract: Systems and methods are provided for decoding signal vectors in multiple-input multiple-output (MIMO) systems, where the receiver has received one or more signal vectors from the same transmitted vector. The receiver combines the received vectors by vector concatenation The concatenated vector may then be decoded using, for example, maximum-likelihood decoding. In some embodiments, the combined signal vector is equalized before decoding.
    Type: Grant
    Filed: November 21, 2012
    Date of Patent: March 11, 2014
    Assignee: Marvell World Trade Ltd.
    Inventors: Jungwon Lee, Woong Jun Jang, Leilei Song
  • Publication number: 20140064348
    Abstract: Systems and methods are provided for compensating for analog distortion in telecommunication systems. In one aspect, a system is provided for communicating signals having frequencies in multiple frequency bands between at least one base station and at least one terminal device. The system includes a transport section, a digital filter, and a processing device. The transport section includes an analog filter. The analog filter can reduce interference from interfering signals having frequencies in frequency bands adjacent to received signals from an antenna by filtering the received signals. The processing device can modify filter coefficients of the digital filter. The digital filter with the modified filter coefficients can compensate for distortion in the received signals caused by the analog filter.
    Type: Application
    Filed: September 6, 2013
    Publication date: March 6, 2014
    Applicant: ANDREW LLC
    Inventors: Oliver Braz, Markus Mederle, Van E. Hanson, Nelson Christian Schmidt, JR.
  • Patent number: 8665760
    Abstract: A method and arrangement for connecting an ad-hoc communication network (101) to a permanent communication network (102), e.g. to a cellular mobile communication network. The ad-hoc communication network is established between communication devices (103-106) and a gateway device (107) using a routing protocol that is run in the gateway device and in the communication devices. A protocol address that is associated in a communication device with a protocol data unit is determined on the basis of a control action given by a user of the communication device. In a gateway device, the protocol data unit is relayed to the permanent communication network if the protocol data unit is provided with a pre-determined protocol address. The user of the communication device can determine with the aid of the control action whether he is communicating only inside the ad-hoc communication network or via the permanent communication network.
    Type: Grant
    Filed: January 22, 2008
    Date of Patent: March 4, 2014
    Assignee: Savox Communications Oy AB (Ltd)
    Inventors: Hasse Sinivaara, Pasi Auranen
  • Patent number: 8665933
    Abstract: A data transmitting and receiving device and method are used for saving powers and maintaining the connection quality, stability and continuous link. The method includes the step of gradually adjusting the de-emphasis of the signal transmitted from the data transmitting and receiving device according to the setting value thereof. The method also includes the steps of transmitting training sequence signal with an amplitude and the default de-emphasis by the data transmitting and receiving device to the remote device, receiving the training sequence signal from the remote device, thereby the channel attenuation is estimated using the method, and a better de-emphasis is set up. Then, the data transmitting and receiving device gradually increases the amplitude of the training sequence signal and re-transmits it until the remote device receives the training sequence signal transmitted therefrom.
    Type: Grant
    Filed: May 27, 2011
    Date of Patent: March 4, 2014
    Assignee: Realtek Semiconductor Corp.
    Inventors: Liang-Wei Huang, Mei-Chao Yeh, Tzu-Han Hsu, Li-Han Liang
  • Patent number: 8666005
    Abstract: Method and apparatuses are disclosed to substantially compensate for various unwanted interferences and/or distortions within a communications receiver. Each of these apparatuses and methods estimate the various unwanted interferences and/or distortions within the communications receiver. Each of these apparatuses and methods remove the estimates of the various unwanted interferences and/or distortions within the communications receiver from one or more communications signals within the communications receiver to substantially compensate for the various unwanted interferences and/or distortions.
    Type: Grant
    Filed: June 30, 2011
    Date of Patent: March 4, 2014
    Assignee: Broadcom Corporation
    Inventors: Ramon Alejandro Gomez, Bruce J. Currivan, Massimo Brandolini, Young Shin, Francesco Gatta, Hanli Zou, Loke Kun Tan, Lin He, Thomas Joseph Kolze, Leonard Dauphinee, Robindra Joshi, Binning Chen
  • Patent number: 8666000
    Abstract: A receiver may be operable to receive an inter-symbol correlated (ISC) signal, and generate a plurality of soft decisions as to information carried in the ISC signal. The soft decisions may be generated using a reduced-state sequence estimation (RSSE) process. The RSSE process may be such that the number of symbol survivors retained after each iteration of the RSSE process is less than the maximum likelihood state space. The plurality of soft decisions may comprise a plurality of log likelihood ratios (LLRs). Each of the plurality of LLRs may correspond to a respective one of a plurality of subwords of a forward error correction (FEC) codeword.
    Type: Grant
    Filed: June 20, 2013
    Date of Patent: March 4, 2014
    Assignee: MagnaCom Ltd.
    Inventors: Amir Eliaz, Ilan Reuven
  • Patent number: 8660226
    Abstract: Systems and methods for multichannel noise reduce are provided. One method includes acquiring a multichannel signal, obtaining a noise correlation between a plurality of channels of the multichannel signal, and obtaining a signal characteristic in each of the plurality of channels. The method also includes removing signal noise based on (i) the correlated noise and (ii) at least one of an uncorrelated noise in each channel or the obtained signal characteristic in each channel.
    Type: Grant
    Filed: January 19, 2011
    Date of Patent: February 25, 2014
    Assignee: General Electric Company
    Inventors: Suresh Narayanan Narayanan, Naveen Stephan Chandra, Jiahua Fan
  • Patent number: 8660218
    Abstract: Systems and methods are disclosed for detecting and/or measuring signals contained in modulated sample data, and that may be implemented in one embodiment to detect and measure signals by producing a representation and/or visualization of the signal information of the wide band spectral environment. Signals may be detected and/or measured by demodulating and estimating signal spectra from the modulated sample data that contain the individual signals, and by then forming a frequency representation of the demodulated Nyquist zone spectral estimates into a visual representation in which the frequency of the original signals is visible or otherwise indicated.
    Type: Grant
    Filed: January 30, 2012
    Date of Patent: February 25, 2014
    Assignee: L-3 Communications Integrated Systems LP
    Inventors: Ray Maleh, Frank A. Boyle, Gerald L. Fudge
  • Patent number: 8660219
    Abstract: A radar detector determines whether an input signal is an orthogonally frequency division multiplexed (OFDM) signal or a radar signal by applying at least first and second bandpass filtering operations having substantially non-overlapping passbands to the input signal, each filtering operation having a passband of width substantially less than a relatively large instantaneous bandwidth characteristic of an OFDM signal and substantially greater than a relatively small instantaneous bandwidth characteristic of a radar signal. The detector multiplies power levels of output signals of the first and second filtering operations to form a power product signal and compares the power level of the power product signal with a threshold level and providing an indicating signal in a first state if the power level of the power product signal exceeds the threshold level and otherwise providing said indicating signal in a second state.
    Type: Grant
    Filed: April 3, 2012
    Date of Patent: February 25, 2014
    Assignee: Summit Semiconductor LLC
    Inventor: Kenneth A. Boehlke
  • Publication number: 20140050279
    Abstract: Provided are a receiver, a transmitter and a radio communication method capable of using non-orthogonal multiple access while suppressing cost increase and processing delay. A mobile station 200A receives non-orthogonal signals, also receives a reference signal to be used for interference cancellation, and extracts the non-orthogonal signal addressed to the mobile station 200A from the received non-orthogonal signals by demodulating and cancelling the radio signal addressed to another mobile station. In addition, the mobile station 200A demodulates the extracted non-orthogonal signal addressed to the mobile station 200A on the basis of the reference signal. The reference signal is multiplexed in the same radio resource block as a resource block allocated to the non-orthogonal signals, and is multiplexed in the radio resource block only when at least one signal is scheduled in the radio resource block.
    Type: Application
    Filed: May 17, 2012
    Publication date: February 20, 2014
    Applicant: NTT DOCOMO, INC.
    Inventor: Yoshihisa Kishiyama
  • Patent number: 8654821
    Abstract: A fractional rate converting filter in a wireless transceiver comprising a delay line, multiplier circuit, adder circuit, and selector. The delay line receives a digital input signal at a first sample rate and has delay blocks each providing an output and receiving samples gated at a plurality of clock cycles of an integer sub-multiple frequency of a clock. The outputs are multiplied by corresponding filter tap coefficients. Each filter tap coefficient is spaced by a first integer Y. The adder circuit receives and sums the tap outputs to provide an output signal. The selector iteratively shifts the coefficients by a second integer Z. The output of each delay block is multiplied by corresponding shifted filter tap coefficients. The delay blocks are inhibited from receiving another input sample during the plurality of clock cycles. The output signal has a second sample rate at the integer sub-multiple frequency of the clock.
    Type: Grant
    Filed: May 17, 2013
    Date of Patent: February 18, 2014
    Assignee: ICERA, Inc.
    Inventor: Hamid Safiri
  • Patent number: 8654831
    Abstract: A signal detection apparatus detects the frequency of an input signal without using a PLL. The detection apparatus includes a first and a second orthogonalizer, a phase difference calculator and an integrator, to control the variable coefficient a1 of a band-pass filter. Information e[k]=M·sin(?) representing the phase difference ? between the input data x[k] and the output data y[k] is calculated with the first and second orthogonalizers and the phase difference calculator. The sign of e[k] is inverted and a predetermined integral calculation is performed with the integrator, and the calculated integral value is set as the coefficient a1 of the band-pass filter. Every time input data x[k] is input, the coefficient a1 is changed by reducing it when e[k]>0 and increasing it when e[k]<0. Thus, the frequency of the output signal of the band-pass filter is matched to the input signal.
    Type: Grant
    Filed: September 20, 2011
    Date of Patent: February 18, 2014
    Assignee: Daihen Corporation
    Inventor: Toyokazu Kitano
  • Patent number: 8655300
    Abstract: A wireless receiver (110) for UWB or other format, receives a useful signal in a particular band of frequencies in site spite of interference components inside and outside the particular band of frequencies. An interference detector (130, 535, 555) detects the in band interference component in a first range of frequencies to include the particular band of frequencies. The same receiver circuitry (120, 300, 310, 505) is adapted to receive a second range of frequencies to include frequencies adjacent to the particular band, to detect the out of band interference component. The position of a second interfering signal in the second range is used to detect artifacts caused by spectral folding so that the required frequency of a band reject filter can be found.
    Type: Grant
    Filed: May 23, 2011
    Date of Patent: February 18, 2014
    Assignee: ST-Ericsson SA
    Inventors: Ajay Kapoor, Maurice Stassen
  • Patent number: 8654913
    Abstract: A method and apparatus for processing a signal in a wireless communication system. The method comprises: receiving a signal at a receiver over a wireless channel; sampling the signal to produce a plurality of signal samples; and supplying the samples to an equaliser implemented in software running on a processor of the receiver, the equaliser being configured to process the samples using at least one equaliser time period having a nominal length. The method further comprises dynamically determining one or more characteristics of the channel; in dependence on the determined channel characteristics, dynamically selecting between a first operational state of the equaliser in which the nominal length is used and a second operational state of the equaliser in which an alternative length is used in place of the nominal length; and processing the samples in the equaliser using the determined equaliser time period length.
    Type: Grant
    Filed: March 26, 2009
    Date of Patent: February 18, 2014
    Assignee: ICERA, Inc.
    Inventors: Simon Huckett, Phil Jones, Carlo Luschi
  • Patent number: 8654906
    Abstract: A receiving device includes a FFT unit performing FFT on an input signal of a time domain to transform the input signal into a plurality of signals of frequency domains and outputting the plurality of signals of the frequency domains, a signal extracting unit extracting a signal with a power that is greater than a threshold value from among the plurality of signals of the frequency domains output from the first FFT unit and outputting the extracted signal, an IFFT unit performing IFFT on the extracted signal output from the signal extracting unit, a subtracting unit subtracting the extracted signal output from the IFFT unit from the input signal and outputs a subtracted signal, and a second FFT unit transforming the subtracted signal output from the subtracting unit into a signal of the frequency domain by performing the FFT on the subtracted signal output from the subtracting unit.
    Type: Grant
    Filed: March 1, 2011
    Date of Patent: February 18, 2014
    Assignee: Fujitsu Limited
    Inventor: Tsuyoshi Hasegawa
  • Patent number: 8654912
    Abstract: MIMO transmitter with a reconfigurable pooled digital filter is disclosed. A processor uses the output of an envelope detector to set parameters of the filter to minimize the number of instructions per second and the amount of power required by the filter to perform. The processor uses an algorithm or a lookup table stored in memory to select the combination of filter parameters. The parameters may be selected from at least one of: a number of taps, a filter length, a word length, a coefficient quantization, a sampling rate, bits per sample, a sampling bit, a tap delay and a coefficient length. After selecting a combination of filter parameters, the processor sends a control signal to the adaptive filter. The pooled adaptive filter reconfigures itself in accordance with the selected filter parameters.
    Type: Grant
    Filed: October 10, 2006
    Date of Patent: February 18, 2014
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Joseph R. Cleveland, Eran Pisek
  • Patent number: 8654909
    Abstract: According to an embodiment, a semiconductor integrated circuit includes an amplifier, an interference wave suppression unit, a coupler and a filter control circuit. The interference wave suppression unit includes a filter being controlled to be on or off. The filter is configured to suppress an interference wave component of an amplified signal to output the signal as an output signal when the filter is on. The coupler is configured to detect an input signal or the output signal. The filter control circuit controls the filter to be on when a signal level of a detection input signal or a detection output signal detected by the coupler is greater than or equal to a reference value, and controls the filter to be off when the signal level is smaller than the reference value, at arbitrary determination timing in a period of time between a transmission and a reception.
    Type: Grant
    Filed: September 20, 2011
    Date of Patent: February 18, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Mitsuyuki Ashida, Hideaki Majima
  • Patent number: 8655299
    Abstract: A SAW-less receiver includes an FEM interface module, an RF to IF receiver section, and a receiver IF to baseband section. The RF to IF receiver section includes a frequency translated bandpass filter (FTBPF), an LNA, and a mixing section. The FTBPF includes a switching network and a plurality of baseband impedances. The switching network is operable to couple the plurality of baseband impedances to the FEM interface in accordance with a plurality of phase-offset RF clock signals to RF bandpass filter the inbound RF signal. The LNA amplifies the filtered inbound RF signal and the mixing section mixes the amplified inbound RF signal with a local oscillation to produce an inbound IF signal. The receiver IF to baseband section converts the inbound IF signal into one or more inbound symbol streams.
    Type: Grant
    Filed: March 30, 2011
    Date of Patent: February 18, 2014
    Assignee: Broadcom Corporation
    Inventors: Ahmad Mirzaei, Hooman Darabi
  • Publication number: 20140044224
    Abstract: A system including a filter and a downconverter. The filter is configured to receive, from a node, (i) a first signal and (ii) a second signal, and filter the second signal. The filter includes a first input impedance. The filter comprises a first plurality of switches and a first circuit. The first plurality of switches is configured to communicate with the node. The first plurality of switches is clocked at a first frequency. The first frequency is based on a frequency of the first signal. The first circuit is configured to communicate with an output of the plurality of switches. The first circuit includes a second input impedance. The second input impedance is different than the first input impedance. The downconverter is configured to (i) receive the first signal and (ii) downconvert the first signal. The filter and the downconverter are connected in parallel to the node.
    Type: Application
    Filed: October 22, 2013
    Publication date: February 13, 2014
    Applicant: Marvell World Trade Ltd.
    Inventors: Brian Brunn, Gregory Uehara, Sehat Sutardja
  • Patent number: 8649472
    Abstract: A plurality of sub-channel response estimates corresponding to a plurality of contiguous sub-channels in a communication channel are determined, and a plurality of weight coefficients are determined. The plurality of sub-channel response estimates are multiplied with the plurality of weight coefficients to generate a plurality of weighted sub-channel response estimates. A filtered sub-channel response estimate for one of the plurality of contiguous sub channels is generated using the plurality of weighted sub-channel response estimates.
    Type: Grant
    Filed: February 4, 2013
    Date of Patent: February 11, 2014
    Assignee: Marvell International Ltd.
    Inventors: Robhit U. Nabar, Arul Durai Murugan Palanivelu
  • Patent number: 8649729
    Abstract: A system and method are provided for transmitting a broadband interference signal and allowing communication through the transmitted interference signal. The system includes an interference transmitter for transmitting the interference signal, the interference transmitter having a transmitter feeder and a first antenna; a radio receiver for receiving a radio signal, the radio receiver having a radio feeder and a second antenna collocated with the first antenna of the interference transmitter; a steering signal generator for introducing at least one steering signal into the interference signal at the transmit feeder; a first directional coupler for sampling a portion of the interference signal that includes at least one of the steering signals; a negative feedback loop for adjusting the amplitude and phase of the sampled portion of the interference signal; and a second directional coupler for coupling the adjusted sampled portion of the interference signal into the radio feeder.
    Type: Grant
    Filed: November 20, 2009
    Date of Patent: February 11, 2014
    Assignee: Cobham CTS Limited
    Inventors: Stephen James Nightingale, George John Woloszczuk