Amplitude Modulation Patents (Class 375/320)
  • Publication number: 20150003564
    Abstract: A transmitter apparatus wherein a simple structure is used to successfully suppress the degradation of error rate performance that otherwise would be caused by fading or the like. There are included encoding parts that encode transport data; a mapping part that performs such a mapping that encoded data sequentially formed by the encoding parts are not successively included in the same symbol, thereby forming data symbols; and a symbol interleaver that interleaves the data symbols. In this way, a low computational complexity can be used to perform an interleaving process equivalent to a bit interleaving process to effectively improve the reception quality at a receiving end.
    Type: Application
    Filed: September 16, 2014
    Publication date: January 1, 2015
    Inventors: Yutaka MURAKAMI, Shutai Okamura, Kiyotaka Kobayashi, Masayuki Orihashi, Kazuaki Takahashi
  • Patent number: 8923444
    Abstract: A receiver for decoding a communication signal is disclosed. The receiver includes an input port and a filter. The input port receives the communication signal from a communication medium. The communication signal comprises a sequence of symbols. Each symbol of the symbol sequence is an analog pulse that has a leading edge of exponential shape. The exponential shape has an exponential growth parameter value that has been selected from values ?0 and ?1, which are distinct positive values. For each symbol of the symbol sequence, the exponential growth parameter value for the leading edge of the symbol has been selected based on a corresponding bit from a stream of information bits. The filter receives the communication signal from the input port and filters the communication signal to obtain an output signal. The transfer function of the filter has one or more zeros at ?0.
    Type: Grant
    Filed: June 30, 2014
    Date of Patent: December 30, 2014
    Assignee: Board of Regents, The University of Texas System
    Inventor: Robert H. Flake
  • Publication number: 20140376666
    Abstract: A receiver stage for receiving a receive signal comprises M receiving paths, each receiving path comprises a signal processor and K comparators. The signal processors of the M receiving paths are configured to generate, for each of the M receiving paths, an amplified version of the receive signal, such that an amplification gain of the respective receiving path increases from a first of the M receiving paths to a last of the M receiving paths. For each of the M receiving paths the K comparators of the respective receiving paths are configured to compare the amplified receive signal of the respective receiving path with a respective threshold value. For each of the M receiving paths the threshold value increases from a first of the K comparators to the last of the K comparators.
    Type: Application
    Filed: September 4, 2014
    Publication date: December 25, 2014
    Inventors: Frank OEHLER, Markus EPPEL, Heinrich MILOSIU
  • Publication number: 20140376418
    Abstract: Embodiments of this invention describe a method to reduce the effective inter carrier spacing between the sub-carriers of wireless, wired or optical transmissions and thereby increase the spectral efficiency of the communication system. Signal transmitted from multiple transmit chains are shifted in frequency at the transmitter. At the receiver a plurality of receive chains is used, the received signals are similarly shifted in frequency and used to reduce the inter carrier interference. Embodiments also describe a method for Full Duplex communication where the transmitters transmit using different frequency shifts. The receiver receives the transmitted signal and an echo of it's transmission. As the received transmission is shifted in frequency from it's transmission, it can cancel out the echo and receive the intended signal.
    Type: Application
    Filed: June 25, 2013
    Publication date: December 25, 2014
    Inventor: Raja BANERJEA
  • Publication number: 20140369445
    Abstract: A decision circuit includes: a first decision block to distinguish a first bit of bits using an amplitude of an analog signal as a discrimination point, the analog signal being an amplitude shift keyed signal; a superposition block to acquire an absolute value of a difference of the analog signal in respect to an amplitude center value of the analog signal by superposing divided analog signals; an inversion block to control inverting of the signal based on a first distinction result of the first decision block; a second decision block to distinguish a second bit of the bits based on an amplitude of an output signal from the inversion block and the discrimination point; and an output buffer to output the first distinction result and a second distinction result of the second decision block in synchronization with a clock.
    Type: Application
    Filed: March 19, 2014
    Publication date: December 18, 2014
    Applicant: FUJITSU LIMITED
    Inventors: Takashi Shimizu, Jun Matsui, Tsuyoshi Yamamoto
  • Patent number: 8908778
    Abstract: A rail-to-rail comparator including a first comparison unit connected to a first terminal and configured to compare differential input signals to differential reference voltages; a second comparison unit connected to a second terminal and configured to compare the differential input signals to the differential reference voltages; and an output unit configured to be driven in response to a clock signal and to generate a complementary output signal according to comparison results of the first and second comparison units.
    Type: Grant
    Filed: August 21, 2012
    Date of Patent: December 9, 2014
    Assignee: SK Hynix Inc.
    Inventors: Jin Il Chung, Jun Hyun Chun, Jin Wook Burm, Dae Ho Yun
  • Patent number: 8908781
    Abstract: A receiver and method for receiving and processing a sequence of transmitted symbols in a digital communication system utilizing soft pilot symbols. A set of soft pilot symbols are transmitted with higher reliability than the remaining symbols in the sequence by modulating the soft pilot symbols with a lower order modulation such as BPSK or QPSK while modulating the remaining symbols with a higher order modulation such as 16 QAM or 64 QAM. The receiver knows the modulation type and location (time/frequency/code) of the soft pilot symbols, and demodulates them first. The receiver uses the demodulated soft pilot symbols as known symbols to estimate parameters of the received radio signal. Unlike traditional fixed pilots, the soft pilots still carry some data. Additionally, the soft pilots are particularly helpful in establishing the amplitude reference essential in demodulating the higher order modulation symbols.
    Type: Grant
    Filed: February 23, 2012
    Date of Patent: December 9, 2014
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventors: Douglas Cairns, Elias Jonsson
  • Patent number: 8908799
    Abstract: Systems and methods of performing ASK or QAM modulation with uneven distance between symbols are provided. Different bit positions mapped to such symbols are assigned to different receivers, with the result that there are different BER performances among bits sent from a transmitter to the different receivers. Bits for multiple receivers are mapped to a UASK constellation or a UQAM constellation without using superposition.
    Type: Grant
    Filed: August 15, 2008
    Date of Patent: December 9, 2014
    Assignee: Blackberry Limited
    Inventors: Shouxing Qu, Yan Xin, Johanna Lisa Dwyer
  • Publication number: 20140348268
    Abstract: A method is provided for modulating a real data stream grouped into blocks of nb.M real data, where M is the number of carriers and nb is an integer greater than or equal to 2. The method includes, for a block of real data: a first modulation by a first modulator of the first M/2 data, delivering a first set of modulated carriers; a second modulation by a second modulator of the following (nb?1).M data, delivering a second set of (nb?1).M modulated carriers; a third modulation by a third modulator of the last M/2 data, delivering a third set of modulated carriers; and a superposition of the first, second and third sets, forming a block of OFDM/OQAM symbols of length nb.M/2, the first set being superposed with the start of the second set and the third set being superposed with the end of the second set.
    Type: Application
    Filed: January 9, 2013
    Publication date: November 27, 2014
    Inventors: Pierre Siohan, Youssef Dandach
  • Publication number: 20140348267
    Abstract: A low latency transmitter and receiver for an OFDM system are disclosed. The low latency transmitter includes an FFT module and a baseband modulator. The FFT module computes IDFT of PSK constellation data symbols or QAM constellation data symbols. The baseband modulator performs complex modulation of the IDFT samples by multiplying these samples with 1 and ?1 alternatively in time domain. The low latency receiver includes a baseband demodulator and another FFT module. The baseband demodulator performs complex demodulation of the received samples of OFDM symbols by multiplying the samples of OFDM symbols with 1 and ?1 alternatively in time domain thereby obtaining baseband demodulated symbols. The FFT module of the receiver computes DFT of samples of the baseband demodulated symbols to obtain samples of the OFDM demodulated symbols.
    Type: Application
    Filed: May 22, 2013
    Publication date: November 27, 2014
    Applicant: Uurmi Systems Private Limited
    Inventor: Nanda Kishore Chavali
  • Patent number: 8891686
    Abstract: Methods for detecting and/or indicating the presence of valid data and threshold setting and data detection circuitry are disclosed. The threshold setting and data detection circuitry and related methods may be useful for fast and accurate reception of optical signals. The detection circuit generally comprises (i) a first circuit configured to regulate or control a DC offset of a differential input signal, and (ii) a second circuit coupled to the first circuit, the second circuit configured to indicate the presence of a data signal at the differential input signal when a voltage difference between true and complementary nodes of the differential input signal is above a predetermined threshold.
    Type: Grant
    Filed: October 26, 2011
    Date of Patent: November 18, 2014
    Assignee: Source Photonics, Inc.
    Inventors: Mohammad Azadeh, Near Margalit
  • Patent number: 8874050
    Abstract: A circuit and method for a saturation correction of a power amplifier (PA) is provided in order to maintain a desirable switching spectrum. The circuit includes a closed loop system that is responsive to a dynamic PA control signal known as VRAMP. The method samples a detector voltage that represents the output of the PA at the maximum voltage level of VRAMP. The sampled detector voltage is then reduced by a predetermined amount and applied as a fixed voltage PA control signal in the place of VRAMP. As a result, the closed loop system responds to the fixed voltage PA control signal to bring the PA out of saturation before VRAMP can begin a voltage decrease. Once the VRAMP voltage decreases, VRAMP is reapplied as a dynamic PA control signal in place of the fixed voltage control signal.
    Type: Grant
    Filed: May 5, 2010
    Date of Patent: October 28, 2014
    Assignee: RF Micro Devices, Inc.
    Inventors: Alexander Wayne Hietala, Jeffery Peter Ortiz, Timothy Keith Coffman
  • Publication number: 20140307832
    Abstract: One or more embodiments provides method for transmitting a signal by a transmitting apparatus in wireless a communication system supporting a modulation scheme based on a quadrature amplitude modulation (QAM) scheme and a frequency shift keying (FSK) scheme. The method includes determining at least one first bit which will be mapped to at least one QAM symbol and at least one second bit which will be mapped to at least one FSK symbol among bits included in an encoded input bit stream; and generating a modulation symbol by mapping the at least one first bit to the at least one QAM symbol and mapping the at least one second bit to the at least one FSK symbol based on a Hamming distance of the at least one second bit.
    Type: Application
    Filed: April 15, 2014
    Publication date: October 16, 2014
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Min Sagong, Won-Il Roh, Jeong-Ho Park, Ji-Yun Seol, Hyun-Kyu Yu, Chi-Woo Lim, Kyung-Whoon Cheun, Jae-Weon Cho, Sung-Nam Hong
  • Publication number: 20140301505
    Abstract: A receiving device including: a demodulation circuit configured to generate first likelihood data of reception symbols based on a transmission format of the reception symbols, the transmission format being selected from transmission formats and including a modulation scheme applied to the reception symbols, the modulation scheme being one of amplitude modulation schemes, a processor configured to estimate a scale ratio of an implementation scale to a theoretical scale, the implementation scale being a scale of the first likelihood data, the theoretical scale being a scale of second likelihood data of the reception symbols, the second likelihood data being defined by a theory and not depending on an implementation of the receiving device, and to generate the second likelihood data based on the first likelihood data and the scale ratio, and a decoding circuit configured to decode the second likelihood data based on the transmission format.
    Type: Application
    Filed: March 26, 2014
    Publication date: October 9, 2014
    Applicant: FUJITSU LIMITED
    Inventor: Shunji MIYAZAKI
  • Patent number: 8855236
    Abstract: A transmitter using quadrature modulation includes a rectangular to polar converter for converting data symbols into a polar form, where each polar symbol has a magnitude signal and an angle signal. Digital phase modulation circuitry includes an all digital PLL circuit for generating a phase modulated RF carrier signal responsive to the angle signal frequency control word (FCW) and a carrier frequency FCW. A digitally controlled amplifier for amplifying the phase modulated signal is controlled by a digital amplitude control circuitry for controlling the gain of the digitally controlled amplifier responsive to the magnitude signal.
    Type: Grant
    Filed: September 20, 2011
    Date of Patent: October 7, 2014
    Assignee: Texas Instruments Incorporated
    Inventors: Robert B. Staszewski, Sameh Rezeq, Dirk Leipold
  • Patent number: 8842780
    Abstract: An apparatus for demodulating an Amplitude Shift Keying (ASK) encoded signal is provided. The apparatus comprises a peak detector, a first comparator, a threshold generator, a delay circuit, and a second comparator. The peak detector is configured to detect a peak voltage, and the first comparator is coupled to the peak detector and receives a first threshold voltage. The threshold generator is coupled to the peak detector and is configured to generate a second threshold voltage that is proportional to peak voltage. The delay circuit is coupled to the first comparator, and the second comparator is coupled to the delay circuit and that is coupled to the threshold generator so as to receive the second threshold voltage.
    Type: Grant
    Filed: December 16, 2011
    Date of Patent: September 23, 2014
    Assignee: Texas Instruments Incorporated
    Inventors: Anant S. Kamath, Sriram Ramadoss, Shrinivasan Jaganathan
  • Publication number: 20140270001
    Abstract: In an example, there is disclosed a system and method for detecting and correcting error in a quadrature receiver (QR). The QR may include a receiver channel operable to divide a received RF signal into I and Q channels. The receiver channel may include error sources, such as (in sequence) pre-demodulation (PD) error, LO mixer error, and baseband (BB) error. Test tones may be driven on the receiver channel at a plurality of test frequencies, and a quadrature error corrector may be provided to detect error from each source. Upon receiving an RF signal, the quadrature error corrector may apply correction coefficients to correct each source of error in reverse sequence (BB, LO, PD).
    Type: Application
    Filed: March 14, 2014
    Publication date: September 18, 2014
    Applicant: ANALOG DEVICES, INC.
    Inventors: Richard P. SCHUBERT, Mariko MEDLOCK, Wei An
  • Publication number: 20140270000
    Abstract: There are disclosed systems and methods for computing a reliability value for a bit of a received symbol value y associated with a constellation. In one embodiment, the method comprises computing the reliability value by obtaining a first minimum distance value, the first minimum distance value being a function of an absolute magnitude of an initial value associated with the bit, and combining the first minimum distance value with a second minimum distance value, the second minimum distance value being a function of a distance between the received symbol value y and a symbol x{circumflex over (b)} in the constellation corresponding to a most likely pattern of bits transmitted given the received symbol value y.
    Type: Application
    Filed: March 14, 2013
    Publication date: September 18, 2014
    Applicant: RESEARCH IN MOTION LIMITED
    Inventors: Xiang LIU, Martin KOSAKOWSKI
  • Publication number: 20140269992
    Abstract: An apparatus and a method for operating a transmission end in a wireless communication system that supports Frequency and Quadrature-Amplitude Modulation (FQAM) are provided. The method includes dividing an information bit stream into a plurality of portions, encoding each of the plurality of portions using different encoding schemes, and generating an FQAM symbol by combining result values of the encoding of each of the plurality of portions, wherein the encoding schemes are different according to at least one of an encoding order, an encoding rate, an input size, and an encoding technique.
    Type: Application
    Filed: March 11, 2014
    Publication date: September 18, 2014
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Sung-Nam HONG, Min SAGONG, Chi-Woo LIM, Hyun-Kyu YU, Kyung-Whoon CHEUN
  • Publication number: 20140270002
    Abstract: In an example, there is disclosed a system and method for detecting and correcting error in a quadrature receiver (QR). The QR may include a receiver channel operable to divide a received RF signal into I and Q channels. The receiver channel may include error sources, such as (in sequence) pre-demodulation (PD) error, LO mixer error, and baseband (BB) error. Test tones may be driven on the receiver channel at a plurality of test frequencies, and a quadrature error corrector may be provided to detect error from each source. Upon receiving an RF signal, the quadrature error corrector may apply correction coefficients to correct each source of error in reverse sequence (BB, LO, PD).
    Type: Application
    Filed: March 14, 2014
    Publication date: September 18, 2014
    Applicant: ANALOG DEVICES, INC.
    Inventors: Richard P. SCHUBERT, Mariko MEDLOCK, Wei An
  • Patent number: 8824599
    Abstract: A receiver may be operable to generate, utilizing a sequence estimation process, estimates of transmitted symbols which may comprise information symbols and one or more pilot symbols. For each of the information symbols, a corresponding one of the generated estimates may be selected from a first set of one or more values based on a search. For each of the one or more pilot symbols, a corresponding one of the generated estimates may be selected from a second set of one or more values based on a predetermination. The second set of one or more values may comprise one or more symbol values predetermined as corresponding to the one or more pilot symbols. Each of the values in the second set may comprise a known value in a modulation symbol constellation associated with the information symbols. Power of each of the one or more pilot symbols may be zero power.
    Type: Grant
    Filed: January 31, 2013
    Date of Patent: September 2, 2014
    Assignee: MagnaCom Ltd.
    Inventor: Amir Eliaz
  • Patent number: 8817910
    Abstract: Systems and methods of performing ASK or QAM modulation with uneven distance between symbols are provided. These are used to provide differing BER performances among bits sent from a transmitter to a receiver.
    Type: Grant
    Filed: August 15, 2008
    Date of Patent: August 26, 2014
    Assignee: Blackberry Limited
    Inventors: Shouxing Qu, Yan Xin, Johanna Lisa Dwyer, Paul Carpenter
  • Publication number: 20140226754
    Abstract: Disclosed is a method of transmitting dual digital signals through a single antenna. The method includes receiving, by a transmitter, a first data stream and a second data stream which use the same carrier frequency, modulating, by the transmitter, each of the first data stream and the second data stream, lowering, by the transmitter, a power level of the modulated second data stream, combining, by the transmitter, the modulated first data stream and the second data stream with the lowered power level, and transmitting, by the transmitter, the added first data stream and second data stream to a single antenna in the same channel.
    Type: Application
    Filed: October 28, 2013
    Publication date: August 14, 2014
    Applicant: GCT Semiconductor, Inc.
    Inventors: Eal Wan LEE, Dae Hong KIM, Jeong Min KIM
  • Publication number: 20140226760
    Abstract: A method of generating modulation signals is disclosed including generally three steps. A plurality of modulation signals are generated, each of which is to be transmitted from a different one of a plurality of antennas in an identical frequency band, wherein each modulation signal includes a pilot symbol sequence including a plurality of pilot symbols used for demodulation. Each of the pilot symbol sequences is inserted at the same temporal point in each modulation signal, wherein the pilot symbol sequences are orthogonal to each other with zero mutual correlation among the plurality of modulation signals, each pilot symbol having a non-zero amplitude, the quantity of the plurality of pilot symbols in each sequence being greater than the quantity of the plurality of modulation signals to be transmitted. The plurality of modulation signals each including different transmission data and one of the pilot symbol sequences are output to the antennas.
    Type: Application
    Filed: April 18, 2014
    Publication date: August 14, 2014
    Applicant: Panasonic Corporation
    Inventors: Yutaka Murakami, Masayuki Orihashi, Akihiko Matsuoka
  • Publication number: 20140226755
    Abstract: The present invention relates to a method of transmitting and receiving signals and a corresponding apparatus. One aspect of the present invention relates to a method of receiving a signal, which includes interleaving in an appropriate manner for a channel bonding system. The interleaving can allow decoding a user requested service at a random tuner window position.
    Type: Application
    Filed: April 9, 2014
    Publication date: August 14, 2014
    Applicant: LG Electronics Inc.
    Inventors: Woo Suk KO, Sang Chul MOON
  • Patent number: 8804605
    Abstract: Systems and methods are disclosed for feeder link configurations to layered modulation. One feeder link system employs feeder link spot beam to antennas in distinct coverage areas to enable frequency reuse. Another system employs narrow beam width feeder link antenna to illuminate individual satellites also enabling frequency reuse. Yet another system uses layered modulation in the feeder link. Another feeder link system employs a higher order synchronous modulation for the satellite feeder link than is used in the layered modulation downlink signals.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: August 12, 2014
    Assignee: The DIRECTV Group, Inc.
    Inventors: Paul R. Anderson, Joseph Santoru, Ernest C. Chen
  • Patent number: 8805680
    Abstract: Provided are a method and an apparatus for encoding and decoding an audio signal. A method for encoding an audio signal includes receiving a transformed audio signal, dividing the transformed audio signal into a plurality of subbands, performing a first sinusoidal pulse coding operation on the subbands, determining a performance region of a second sinusoidal pulse coding operation among the subbands on the basis of coding information of the first sinusoidal pulse coding operation, and performing the second sinusoidal pulse coding operation on the determined performance region, wherein the first sinusoidal pulse coding operation is performed variably according to the coding information. Accordingly, it is possible to further improve the quality of a synthesized signal by considering the sinusoidal pulse coding of a lower layer when encoding or decoding an audio signal in an upper layer by a layered sinusoidal pulse coding scheme.
    Type: Grant
    Filed: May 19, 2010
    Date of Patent: August 12, 2014
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Mi-Suk Lee, Heesik Yang, Hyun-Woo Kim, Jongmo Sung, Hyun-Joo Bae, Byung-Sun Lee
  • Publication number: 20140219396
    Abstract: A method in a QAM receiver (100) for performing timing recovery. The QAM receiver (100) is configured to receive a sequence of symbols. Each symbol is represented by a respective IQ pair comprising a respective inphase component I and a respective quadrature component Q. The QAM receiver (100) samples the respective I component and the respective Q component with a relative timing offset between the sampling of the respective I component and the respective Q component. The QAM receiver (100) establishes a first value associated to a quality of the I component samples, and a second value associated to a quality of the Q component samples, and compares the first value and second value to determine if the sampling timing should be advanced or delayed to improve the sample quality. The QAM receiver (100) adjusts subsequent sampling by advancing or delaying a sampling timing based on the comparison.
    Type: Application
    Filed: September 23, 2011
    Publication date: August 7, 2014
    Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
    Inventor: Christer Svensson
  • Publication number: 20140211887
    Abstract: A method for supporting Time-Quadrature Amplitude Modulation (TQAM) in a wireless communication system includes generating a transmission symbol identified by a combination of a QAM symbol and a position of a time resource to which the QAM symbol is mapped, shifting at least one QAM symbol among QAM symbols contained in the transmission symbols with respect to a time axis, and readjusting a constellation point of the QAM symbol on the basis of a shifting quantity. A method for operating a receive end comprises receiving a reception symbol identified by a combination of a QAM symbol and a position of a time resource to which the QAM symbol is mapped, restoring at least one QAM symbol shifted in a transmit end for uniformizing of the time-axis distribution of QAM symbols contained in the reception symbols, generating decoding metrics for the reception symbol, and performing decoding the reception symbol using the decoding metric.
    Type: Application
    Filed: January 28, 2014
    Publication date: July 31, 2014
    Applicant: Samsung Electronics Co., Ltd
    Inventors: Min Sagong, Chi-Woo Lim, Sung-Nam Hong, Hyun-Kyu Yu, Kyung-Whoon Cheun
  • Patent number: 8792591
    Abstract: Disclosed herein are systems and methods for accurate removal of I/Q mismatch in received signals of an analog FM receiver. The analog FM receiver includes a down-converter, a calibration circuit that estimates I/Q mismatch values, and a compensation circuit that uses the estimated mismatch values to reduce the effects of I/Q mismatch. In one aspect, the calibration circuit uses an adaptive dual-parameter compensation scheme to iteratively correct the received signals by approximating a coefficient value and an amplitude value that minimize the signals' amplitude variation from the amplitude value. In another aspect, phase and amplitude mismatch parameters can be determined using the coefficient value.
    Type: Grant
    Filed: November 3, 2011
    Date of Patent: July 29, 2014
    Assignee: Marvell International Ltd.
    Inventor: Chris Cheng-Chieh Lee
  • Publication number: 20140198881
    Abstract: A communication apparatus comprises an inserter that inserts an element having a value of 0 or nearly 0 into a predetermined position of a modulated signal to generate inserted data; an operator that adds a pilot signal comprising a data series of which the elements at the positions corresponding to the predetermined positions in the modulated signal are multiplied by a first amplitude coefficient and the elements other than the elements multiplied by the first amplitude coefficient are multiplied by a second amplitude coefficient to the inserted data to generate a post-operation data; an IFFT unit that performs IFFT on the post-operation data; and a transmitter that generates a baseband signal based on the post-operation data on which the IFFT is performed and transmits a transmission signal generated from the baseband signal.
    Type: Application
    Filed: January 10, 2014
    Publication date: July 17, 2014
    Applicant: ICOM INCORPORATED
    Inventor: Nobuyoshi Nishikawa
  • Publication number: 20140192932
    Abstract: Certain aspects of the method may comprise generating at least one control signal that may be utilized to control at least a first of a plurality of received spatially multiplexed communication signals. An amplitude and/or phase of the first received spatially multiplexed communication signal may be adjusted via the generated control signal so that the amplitude and/or phase of the first received spatially multiplexed communication signal may be equivalent to an amplitude and/or phase of a second received spatially multiplexed communication signal. The amplitude of the first received spatially multiplexed communication signal is adjusted within the processing path used to process the first received spatially multiplexed communication signal.
    Type: Application
    Filed: December 4, 2013
    Publication date: July 10, 2014
    Applicant: Broadcom Corporation
    Inventors: Mark KENT, Vinko ERCEG, Uri M. LANDAU, Peter VAN ROOYEN, Peter ROUX
  • Publication number: 20140192925
    Abstract: The invention relates to a method of reducing Peak-to-Average. Power Ratio in a transmitting device of a filter-hank multi-carrier system, which includes the steps of: performing constellation modulation (210) on data to be transmitted; performing K-point Discrete Fourier Transform (220) on a vector composed of K constellation symbols resulting from the constellation modulation: and performing Offset-Quadrature Amplitude Modulation (230) on a data vector resulting from the Discrete Fourier Transform, wherein the parameter K represents the number of subcarriers allocated for transmission of the data to be transmitted. With the solution proposed by the invention. PAPR of a signal can be significantly reduced without adding a large number of operations to thereby improve the efficiency of a power amplification circuit, to improve effective transmission, power and to alleviate nonlinear distortion of the signal during a power amplification.
    Type: Application
    Filed: July 13, 2012
    Publication date: July 10, 2014
    Applicant: ALCATEL LUCENT
    Inventor: Dong Li
  • Publication number: 20140192931
    Abstract: In one embodiment, an apparatus is provided that includes a first circuit configured and arranged to provide a modulated carrier signal in response to a signal provided from the antenna. The modulated carrier signal conveys data using peaks or amplitudes of the carrier signal. A second circuit is configured to rectify the modulated carrier signal and integrate the rectified signal in response to a first clock signal. A third circuit is coupled to an output of the second circuit and is configured to sample the integrated signal values and provide therefrom a sample-based approximation of the modulated carrier signal.
    Type: Application
    Filed: January 8, 2013
    Publication date: July 10, 2014
    Applicant: NXP B.V.
    Inventors: Remco C. VandeBeek, Massimo Ciacci, Ghiath Al-kadi
  • Patent number: 8774286
    Abstract: A receiving apparatus includes a buffer configured to store packets of a first packet sequence made up of packets extracted from one transport stream that are common to packets of another transport stream and packets of a second packet sequence made up of common packets, a read control section configured to read the packets of the first packet sequence and the second packet sequence stored in the buffer after the passing of a predetermined time after synchronization is established between the packets of the first packet sequence and the packets of the second packet sequence, thereby reconstructing one transport stream from the first packet sequence and the second packet sequence, and an output section configured to output the reconstructed transport stream.
    Type: Grant
    Filed: August 6, 2010
    Date of Patent: July 8, 2014
    Assignee: Sony Corporation
    Inventors: Takashi Yokokawa, Satoshi Okada
  • Patent number: 8774326
    Abstract: A method of operation of a communication system includes: utilizing an estimation module estimating a log-likelihood ratio for a transmission; and utilizing a slicing module, coupled to the estimation module, slicing a constellation by: reading the log-likelihood ratio from the estimation module, defining a threshold within the constellation, and adjusting the threshold based on the log-likelihood ratio for determining a symbol.
    Type: Grant
    Filed: April 8, 2012
    Date of Patent: July 8, 2014
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Chun Kin Au Yeung, Sungsoo Kim, Jungwon Lee
  • Publication number: 20140185657
    Abstract: A system and method are provided for implementing a soft Reed-Solomon (RS) decoding scheme, technique or algorithm to improve physical layer performance in cable modems and cable gateways. At 1024-QAM, a receiver is provided in which a signal to noise ratio is reduced by at least about 1 dB relaxing design considerations and specifications for other components in the system including for the tuner. A soft-RS-symbol generation scheme is provided to enable soft-input RC decoding in a forward error correction (FEC) module connected to a QAM demodulator. The RS decoding scheme is implemented without significantly complicating hardware or processing overhead. A typical receiver hardware requirement in an FEC module to implement the disclosed scheme may be comparatively modest, e.g., on an order of approximately 50K gates.
    Type: Application
    Filed: December 27, 2012
    Publication date: July 3, 2014
    Inventors: Bernard Arambepola, Murat Badem, Parveen K. Shukla, Sahan Gamage, Thushara Hewavithana, Naor Goldman
  • Publication number: 20140177756
    Abstract: A method for transmitting a signal by a signal transmission apparatus in a communication system is provided. The method includes detecting a parameter related to a Quadrature Amplitude Modulation (QAM) scheme and a parameter related to a Frequency Shift Keying (FSK) scheme based on channel quality and an interference component, and modulating information bits using a modulation scheme based on the QAM scheme and the FSK scheme which uses the parameter related to the QAM scheme and the parameter related to the FSK scheme.
    Type: Application
    Filed: December 23, 2013
    Publication date: June 26, 2014
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Jeong-Ho PARK, Tae-Young KIM, Won-Il ROH, Min SAGONG, Ji-Yun SEOL, Hyun-Kyu YU, Kyung-Whoon CHEUN, Jae-Weon CHO, Sung-Nam HONG
  • Publication number: 20140177463
    Abstract: Aspects of the disclosure relate to signal monitoring at edge of a network domain in a network. A monitoring device can evaluate communication quality of information streams in downstream frequency channels, and operation conditions in a telecommunication network. In one aspect, communication quality can be evaluated at the physical layer level or at a higher-layer level containing payload data. In response to an operation issue, the monitoring device can transmit a notification to a node of a distribution platform of the telecommunication network.
    Type: Application
    Filed: February 25, 2014
    Publication date: June 26, 2014
    Applicant: COMCAST CABLE COMMUNICATIONS, LLC
    Inventor: Jorge Salinger
  • Patent number: 8761311
    Abstract: A receiver is an ATSC (Advanced Television Systems Committee)-receiver and comprises a staggered quadrature amplitude modulator for providing an staggered quadrature amplitude modulated (SQAM) signal from a received signal; a data-aided carrier tracking loop (CTL) and a data-aided symbol timing recovery (STR) loop. The data-aided STR loop operates such that the data-aided STR loop is now insensitive to carrier phase offset.
    Type: Grant
    Filed: January 14, 2008
    Date of Patent: June 24, 2014
    Assignee: Thomson Licensing
    Inventor: Maxim Belotserkovsky
  • Publication number: 20140153673
    Abstract: A communication device is configured adaptively to process a receive signal based on noise that may have adversely affected the signal during transition via communication channel. The device may be configured to identify those portions of the signal of the signal that are noise-affected (e.g., noise-affected sub-carriers of an orthogonal frequency division multiplexing (OFDM) signal), or the device may receive information that identifies those portions of the signal that are noise-affected from one or more other devices. The device may be configured to perform the modulation processing of the received signal to generate log-likelihood ratios (LLRs) for use in decoding the signal. Those LLRs associated with noise-affected portions of the signal are handled differently than LLRs associated with portions of the signal that are not noise-affected. The LLRs may be scaled based on signal to noise ratio(s) (SNR(s)) associated with the signal (e.g., based on background noise, burst noise, etc.).
    Type: Application
    Filed: October 31, 2013
    Publication date: June 5, 2014
    Applicant: Broadcom Corporation
    Inventors: Ba-Zhong Shen, Richard S. Prodan, Avi Kliger, Leo Montreuil, Jonathan S. Min, Tak K. Lee, Kelly Brian Cameron, Hau Thien Tran
  • Publication number: 20140153672
    Abstract: A receiver circuit, including a multi-stage QAM de-mapper, for receiving a QAM data signal is disclosed. A first de-mapper circuit recovers a set of encoded data bits from the QAM data signal by calculating a plurality of distances between a received QAM symbol and each of a plurality of possible constellation points. A second de-mapper circuit then generates a set of unencoded data bits for the received QAM symbol based, at least in part, on the plurality of distances calculated by the first de-mapper circuit. The receiver circuit may further include a decoder circuit to decode the set of encoded data bits recovered by the first de-mapper circuit. The second de-mapper circuit may identify a subset of the plurality of possible constellation points based on a result of the decoding and select a constellation point that is associated with the shortest distance of the plurality of distances.
    Type: Application
    Filed: July 19, 2013
    Publication date: June 5, 2014
    Inventors: Lu Zhao, Stefan Brueck, Stephan Schlupkothen, Muhammad Awais Amin, Juan Montojo, Marc W. Werner, Hendrik Schoeneich
  • Publication number: 20140146752
    Abstract: Embodiments of the present disclosure describe methods, apparatuses, and systems related to use of interphase/quadrature component layer shifting in open loop multiple-input, multiple-output communications. Other embodiments may be described and/or claimed.
    Type: Application
    Filed: November 30, 2011
    Publication date: May 29, 2014
    Inventors: Xiaogang Chen, Yuan Zhu, Jong-Kae Fwu, Qinghua Li
  • Patent number: 8737247
    Abstract: A method includes receiving a Code Division Multiple Access (CDMA) carrier carrying at least a pilot channel. Differences are computed between selected soft pilot symbols received on the pilot channel. Based on the computed differences between the selected soft pilot symbols received on the pilot channel, a level of noise is estimated for a data channel that is to be transmitted on the CDMA carrier.
    Type: Grant
    Filed: September 28, 2011
    Date of Patent: May 27, 2014
    Assignee: Marvell International Ltd.
    Inventors: Shimon Moshavi, Gil Katzir, Nimrod Mesika, Maor Margalit
  • Publication number: 20140140444
    Abstract: A compensation apparatus compensates a quadrature-demodulated signal output from a quadrature demodulator 5 that performs quadrature demodulation by using a signal of a carrier frequency fc, by removing an image component caused by the quadrature demodulator 5 from the quadrature-demodulated signal. The compensation apparatus includes a signal generator 10 that generates a reference signal having a predetermined bandwidth in a reception band, and provides the reference signal to an input side of the quadrature demodulator 5. The reference signal includes a frequency band that is biased to either a higher-frequency side or a lower-frequency side with respect to the carrier frequency.
    Type: Application
    Filed: July 24, 2012
    Publication date: May 22, 2014
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Masahiko Onishi, Isao Katsura
  • Publication number: 20140140443
    Abstract: The present invention relates to an injection-locked RF receiver having trifilar transformer splitter. The injection-locked RF receiver includes a trifilar transformer splitter, an injection-locked oscillator and a phase detector. The trifilar transformer splitter includes a primary winding, a secondary winding and a tertiary winding. RF input signal is input to the primary winding. The secondary winding outputs a first differential signal to the injection-locked oscillator. The tertiary winding outputs a second differential signal to the phase detector. Using the trifilar transformer splitter of the invention, the frequency-shift keying demodulation with high sensitivity is achieved, and the number of amplifier can be reduced so as to lower the power consumption of the injection-locked RF receiver and reduce the complexity of the involved system.
    Type: Application
    Filed: April 25, 2013
    Publication date: May 22, 2014
    Applicant: NATIONAL SUN YAT-SEN UNIVERSITY
    Inventors: Tzyy-Sheng Horng, Rong-Fu Ye, Jian-Ming Wu
  • Publication number: 20140140431
    Abstract: A transmitting/receiving system may include a transmission line, a transmitter circuit configured to transmit a clock to the transmission line and to adjust an amplitude of the clock in accordance with a logic level of data, and a receiver circuit configured to receive the clock transferred to the transmission line and to recover the data through detection of the amplitude of the clock.
    Type: Application
    Filed: March 16, 2013
    Publication date: May 22, 2014
    Applicant: SK HYNIX INC.
    Inventor: Hyun-Woo LEE
  • Patent number: 8724658
    Abstract: An output control unit outputs data of bit rate A to a first header-attaching unit and data of bit rate B to a second header-attaching unit. An instructing unit instructs the first or the second header-attaching unit to attach a header of bit rate being the least bit rate to the data of bit rate A or B. The first header-attaching unit creates a header of bit rate A, including an ID of a destination ONU of the data of bit rate A and information concerning the data length, and attaches the header of bit rate A to the data of bit rate A. The second header-attaching unit creates a header of bit rate A, including an ID of the destination ONU of the data of bit rate B and information concerning the data length, and attaches the header of bit rate A to the data of bit rate B.
    Type: Grant
    Filed: May 4, 2012
    Date of Patent: May 13, 2014
    Assignee: Fujitsu Limited
    Inventor: Kazuyuki Mori
  • Patent number: 8718212
    Abstract: Embodiments of the present invention provide a rate matching method and apparatus. The method includes: receiving bit data of a first, a second, and a third input subblock, inserting dummy data into bit data in each subblock to respectively form even-numbered rows and odd-numbered rows of a matrix to be buffered for each subblock; inputting bit data of the even-numbered rows in the even-numbered row buffer and bit data of the odd-numbered rows in the odd-numbered row buffer of each subblock to a second buffer, and forming a matrix by using the bit data of the even-numbered rows and the bit data of the odd-numbered rows; controlling the second buffer to send data at the specified address; selecting data sent by the second buffer; and deleting the dummy data from the selected data to obtain valid output data.
    Type: Grant
    Filed: December 31, 2012
    Date of Patent: May 6, 2014
    Assignee: Huawei Technologies Co., Ltd.
    Inventor: Xin Ma
  • Patent number: 8711953
    Abstract: A method for transmitting a signal from a transmitter over a channel to a receiver on a Power Line Network, wherein said signal is OFDM-modulated on a set of sub-carriers, is proposed, wherein an OFDM tonemap and an eigenbeamforming encoding matrix are determined based on a channel estimation for each sub-carrier, a tonemap feedback signal and an eigenbeamforming feedback signal are generated, which are descriptive of said OFDM tonemap and said eigenbeamforming encoding matrix, respectively, and transmitted to the transmitter. A corresponding receiver, a transmitter, a power line communication and a power line communication system are described as well.
    Type: Grant
    Filed: July 16, 2013
    Date of Patent: April 29, 2014
    Assignee: Sony Corporation
    Inventors: Lothar Stadelmeier, Dietmar Schill, Andreas Schwager, Daniel Schneider