Having Multi-receiver Or Interference Cancellation Patents (Class 375/144)
  • 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 (N×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: 8693590
    Abstract: To detect a special burst sequence, a cross correlation (C) is compared to a square root of an estimated noise variance (?) in conjunction with a threshold value (Th). In one aspect of the disclosure, the threshold value may include multiple threshold values. The multiple threshold values may be compared to an intensity or level of a special burst metric (C/?) to facilitate determination of the special burst sequence. For example, when a special burst metric C/? is greater than a second threshold value (Th2) it may be determined that a special burst sequence exists. However, when the special burst metric C/? is greater than a first threshold value (Th1), but less than the second threshold metric (Th2), it may be determined that detection of a special burst is unclear. In this case, a TFCI value may be used to confirm whether a special burst is detected.
    Type: Grant
    Filed: May 22, 2012
    Date of Patent: April 8, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Insung Kang, Hari Sankar
  • Patent number: 8693523
    Abstract: Filtering and modulating a first rate data signal into a Quadrature Amplitude Modulated (QAM) Code Division Multiple Access (CDMA) and a second rate data signal into a Time Division Multiple Access (TDMA) modulated signal and selecting between the transmission of the CDMA and TDMA modulated signals. A method for nonlinearly and linearly amplifying TDMA and CDMA signals. A diversity receiver and demodulator method for receiving and demodulating transmitted modulated signals. Processing, transmit baseband filtering and modulating signals for providing cross-correlated in-phase and quadrature-phase Gaussian filtered Gaussian Minimum Shift Keying (GMSK) and other cross-correlated modulated signals and spread spectrum Quadrature Phase Shift Keying (QPSK) modulated signals.
    Type: Grant
    Filed: September 3, 2012
    Date of Patent: April 8, 2014
    Inventor: Kamilo Feher
  • Patent number: 8693526
    Abstract: This invention teaches a way to multiplex and de-multiplex unipolar signals using spread spectrum methods. While bipolar spread spectrum signal multiplexing may be used in may applications, for example for systems using radio signals, when using unipolar signals there is a loss of orthogonally which makes the standard algorithms unworkable. This invention teaches a method to recover orthogonally and make spread spectrum multiplexing useful for unipolar signals. One example is in the measurement of optical absorbance along multiple paths simultaneously using light signals, as for functional near infrared spectroscopy (fNIRS).
    Type: Grant
    Filed: February 16, 2012
    Date of Patent: April 8, 2014
    Inventor: Chester Roy Wildey
  • Patent number: 8687527
    Abstract: An inventive method for link adaptation for an LTE/LTE-A uplink with a turbo SIC receiver includes the steps of determining a precoding matrix index PMI and rank index RI selection for an LTE/LTE-A uplink when precoding of the uplink is enabled, responsive to channel state information of a subcarrier in the uplink; determining a decoding order for codewords in the uplink i) when the precoding of the uplink is not enabled and ii) if needed when the precoding of the uplink is enabled; performing modulation and coding scheme MCS assignment for the uplink based on a hard decision successive interference cancellation SIC rule (without intra-CW cancellation) or a partial hard decision successive interference cancellation SIC rule (with intra-CW cancellation), responsive to the determined PMI and RI selection; and influencing data transmission in the uplink responsive to the MCS assignment for detection by a turbo SIC receiver.
    Type: Grant
    Filed: September 16, 2011
    Date of Patent: April 1, 2014
    Assignee: NEC Laboratories America, Inc.
    Inventors: Meilong Jiang, Narayan Prasad, Guosen Yue, Sampath Rangarajan
  • Patent number: 8682621
    Abstract: Methods implementable in a computer system for simulating the transmission of signals are disclosed. The disclosed techniques simulate the effect of the transmitter as well as the channel on a positive and negative pulse, which assures that asymmetry in the transmitter is captured. The resulting positive and negative pulse responses are then used to generate two separate PDFs: one indicative of received logic ‘1’s and another indicative of received logic ‘0’s at a point in time. Generating a plurality of such PDFs at different times allows the reliability of data reception to be assessed, and appropriate sensing margins to be set at a receiver, without the need to simulate the transmission of a very long random stream of data bits.
    Type: Grant
    Filed: July 16, 2010
    Date of Patent: March 25, 2014
    Assignee: Micron Technology, Inc.
    Inventor: Timothy M. Hollis
  • Patent number: 8675751
    Abstract: A method of embedding information within a burst carrier signal, the method comprising modulating meta-data using a modulator such that a meta-carrier signal results, lowering a Power Spectral Density (PSD) of the meta-carrier signal by Direct Sequence Spread Spectrum (DSSS) chipping the meta-carrier signal using a linear Pseudo-Random Number (PRN) sequence, embedding one or more modulated symbols of the meta-carrier signal within an unused portion of one or more quadrants of a modulation constellation of a burst carrier signal such that a composite carrier signal results, and synchronously transmitting the composite carrier signal using a transmitter such that symbols of the meta-carrier signal are synchronized with symbols of the burst carrier signal.
    Type: Grant
    Filed: August 26, 2011
    Date of Patent: March 18, 2014
    Assignee: Comtech EF Data Corp.
    Inventors: Richard Hollingsworth Cannon, Michael Beeler, Cris Mamaril
  • Patent number: 8670509
    Abstract: Adaptive path selection for interference cancellation is provided for wireless communication devices. Signal strength metrics are obtained for each of multiple signal paths. One or more of the signal paths are selected as cancellation candidates in response to determining that the signal paths are associated with a strong interfering path based at least in part on the signal strength metrics for the signal paths and threshold criteria. Cancellation is enabled for an estimated signal generated using the signal paths in response to the signal paths being selected as cancellation candidates.
    Type: Grant
    Filed: March 29, 2012
    Date of Patent: March 11, 2014
    Assignee: Broadcom Corporation
    Inventors: Nelson Sollenberger, Rami Mehio, Wei Luo, Severine Catreux, Sean Truong, Oghenekome Oteri
  • Patent number: 8670344
    Abstract: A method for assisting load scheduling in a wireless communication system comprises computing of an estimate of a noise floor measure for received uplink radio signals and a neighbor cell interference power is estimated. An interference whitening of the received uplink radio signals is performed based on frequency domain equalizing or frequency domain pre-equalizing. A useful signal power after interference whitening is determined and a first user noise floor compensation factor is derived. A noise rise measure is calculated based at least on the useful signal power after interference whitening, the noise floor compensation factor, the noise floor measure and the estimated neighbor cell interference power.
    Type: Grant
    Filed: November 29, 2011
    Date of Patent: March 11, 2014
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventor: Torbjörn Wigren
  • Patent number: 8670478
    Abstract: An arrangement (10) for noise rise estimation comprises a front end signal conditioning arrangement (9) and an interference whitener (14) connected thereto. The interference whitener (10) is arranged for providing interference whitening of a front end signal. A processor (20) is arranged for measuring received total wideband power received at the front end signal conditioning arrangement (9) a plurality of times. An estimate of a noise floor measure is computed by the processor (20) based on the measured received total wideband powers. The processor (20) determines an equivalent total wideband power of the output from the interference whitener (14). The processor (20) also calculates a noise rise measure, based on the equivalent total wideband power and the noise floor measure, and compensates the noise rise measure for the interference whitening. A digital receiver (12) is connected to the output from the interference whitener (14).
    Type: Grant
    Filed: June 10, 2010
    Date of Patent: March 11, 2014
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Ari Kangas, Torbjörn Wigren
  • Patent number: 8665937
    Abstract: A method for noise rise estimation in a wireless communication system comprises receiving (210) of radio signals. An interference whitening (212) is performed. A useful signal power for a first user after the interference whitening is determined (214) for a plurality of time instances. Furthermore, a first user noise floor compensation factor is derived (216) based on combining weights for the first user used in the interference whitening. A probability distribution for a compensated useful signal power for the first user is estimated (218). A conditional probability distribution of a noise floor measure is computed (220). A noise rise measure for the first user is then calculated (222) based at least on the compensated useful signal power for the first user and the conditional probability distribution of a noise floor measure.
    Type: Grant
    Filed: December 10, 2009
    Date of Patent: March 4, 2014
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventor: Karl Torbjörn Wigren
  • Patent number: 8654689
    Abstract: An interference canceller comprises a composite interference vector (CIV) generator configured to produce a CIV by combining soft and/or hard estimates of interference, an interference-cancelling operator configured for generating a soft projection operator, and a soft-projection canceller configured for performing a soft projection of the received baseband signal to output an interference-cancelled signal. Weights used in the soft-projection operator are selected to maximize a post-processing SINR.
    Type: Grant
    Filed: September 28, 2010
    Date of Patent: February 18, 2014
    Assignee: Rambus Inc.
    Inventors: Michael L. McCloud, Vijay Nagarajan
  • Publication number: 20140044153
    Abstract: Methods and apparatus for wireless communication in a wireless communication network that includes receiving a synchronization channel (SCH) signal (including a primary synchronization channel (PSCH) signal, a secondary synchronization channel (SSCH) signal, and a primary scrambling code (PCH) signal) and a part of a common pilot channel (CPICH) signal in the same portion of the slot of the frame. The aspects include determining and summing the PSCH signal, SSCH signal, and PCH signal corresponding to the portion of the slot of the frame. The aspects also include de-spreading the pilot symbol over the portion of the slot of the frame based on the summed PSCH signal, the SSCH signal, and the PCH signal and estimating an estimated pilot symbol for the portion of the slot of the frame, where the estimated pilot symbol is a sum of the de-spread PSCH signal, de-spread SSCH signal, and de-spread PCH signal.
    Type: Application
    Filed: December 21, 2012
    Publication date: February 13, 2014
    Applicant: QUALCOMM Incorporated
    Inventors: Raghavendra Shyam Anand, Yegnesh Srinivasan, Deepti Mani
  • Publication number: 20140036965
    Abstract: A cellular communication system comprises a Multiple-In Multiple-Out (MIMO) transmitter and receiver. The MIMO transmitter comprises a message generator for generating MIMO messages comprising selected training sequences and transceivers transmitting the messages on a plurality of antennas. The training sequences are selected by a midamble selector from a set of training sequences in response to an associated antenna on which the message is to be transmitted. The set of training sequences is associated with the cell of the MIMO transmitter and comprises disjoint subsets of training sequences for each of the plurality of antennas. The receiver comprises a transmit antenna detector which determines which antenna of the MIMO transmitter the message is transmitted from in response to the training sequence of the received message.
    Type: Application
    Filed: October 2, 2013
    Publication date: February 6, 2014
    Applicant: SONY CORPORATION
    Inventors: Peter B. DARWOOD, Vishakan Ponnampalam, Alan Edward Jones
  • Patent number: 8644175
    Abstract: A radio communication system, scheduling method, radio base station device, and radio communication terminal all enabling improvement of the system throughput. The radio base station device (400) comprises a signal demultiplexing section (420), an interference/noise power measuring section (425), and scheduler section (430). The signal demultiplexing section (420) acquires information representing the net reception power of the signal which is transmitted from a mobile terminal and from which the influences of the interference and the noise power are removed. The interference/noise power measuring section (425) measures the interference and noise power components of the uplink. The scheduler section (430) carries out uplink band allocation and MCS selection according to the information representing the net reception power and the uplink interference and noise power components.
    Type: Grant
    Filed: August 13, 2008
    Date of Patent: February 4, 2014
    Assignee: Panasonic Corporation
    Inventors: Atsushi Sumasu, Katsuhiko Hiramatsu
  • Patent number: 8644364
    Abstract: A mobile device receives downlink transmissions comprising replicas of an original downlink transmitted signal over corresponding fingers of a RAKE receiver comprising arithmetic units. The RAKE receiver computes a cell normalization factor for each of active cells and neighbor cells associated with the RAKE receiver. The RAKE receiver uses the same arithmetic units comprising one adder, one multiplier, one divider and/or one square root unit to compute cell normalization factors. The received downlink transmitted signal is processed using the computed cell normalization factors. The RAKE receiver determines signal power from each of other cells, separately, to compute cell normalization factors to normalize fingers of the RAKE receiver. Interference over the normalized fingers are cancelled and used to process the received downlink transmitted signal, which are combined and Turbo decoded.
    Type: Grant
    Filed: November 11, 2009
    Date of Patent: February 4, 2014
    Assignee: Broadcom Corporation
    Inventor: Thirunathan Sutharsan
  • Publication number: 20140029645
    Abstract: A receiving station receives an orthogonal frequency division multiplexing (OFDM) symbol via a shared medium, the OFDM symbol comprising a first set of frequency components modulated with preamble information and a second set of frequency components modulated with information. The receiving station processes sampled values of the received OFDM symbol based on channel characteristics estimated from the first set of frequency components to decode information encoded on a first subset of the second set of frequency components. The receiving station processes sampled values from the first symbol based on channel characteristics estimated from the first set of frequency components and the first subset of the second set of frequency components to decode information encoded on a second subset of the second set of frequency components.
    Type: Application
    Filed: September 26, 2013
    Publication date: January 30, 2014
    Applicant: Qualcomm Incorporated
    Inventors: Lawrence Winston Yonge, III, Srinivas Katar, Arun Avudainayagam
  • Patent number: 8639996
    Abstract: Systems, methods, apparatus, devices and computer program products enhance uplink inter-cell interference cancellation with HARQ retransmissions. The decoding of a data packet depends on whether the interfering packet was decoded. Since the interfering packet is itself transmitted using a HARQ process, the transmission by the victim UT can be accomplished to take this situation into account. The latency of the victim UT can be varied based on the need for energy efficient transmission. In accordance with one specific aspect, if the receiver can decode multiple packets simultaneously, high data rates can be achieved using packet pipelining.
    Type: Grant
    Filed: May 7, 2009
    Date of Patent: January 28, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Petru C. Budianu, Ravi Palanki
  • Patent number: 8630589
    Abstract: Individual radio sets 12a-12e constituting an onboard radio communication system operate together with an adjacent vehicle detection unit (ultrasonic sensors 13a-13e) for detecting a second vehicle adjacent to a first vehicle 11. When it detects the adjacent vehicle, a radio interference decision unit constituting the radio sets 12a-12e decides radio interference due to an onboard radio communication system with the same radio scheme. When it detects the radio interference, a frequency channel switching unit constituting the radio sets 12a-12e switches the frequency channel to be used to avoid the interference of the radio waves.
    Type: Grant
    Filed: April 16, 2009
    Date of Patent: January 14, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Yasunori Hoshihara, Kazuyuki Tanaka, Kinichiro Nishiyama
  • Patent number: 8625656
    Abstract: Techniques for deriving channel estimates with different channel estimation filters are described. In one scheme, a filter selection metric is determined for a signal to be recovered, a channel estimation filter is selected based on the filter selection metric, and a channel estimate is derived with the selected channel estimation filter. In another scheme, a first channel estimate is derived with a first channel estimation filter having a first filter response, a first signal is recovered with the first channel estimate, and interference due to the first signal is estimated and removed. A second channel estimate is derived with a second channel estimation filter having a second filter response that is different from the first filter response.
    Type: Grant
    Filed: March 4, 2010
    Date of Patent: January 7, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Tao Luo, Aleksandar Damnjanovic, Durga Prasad Malladi
  • Patent number: 8619920
    Abstract: A transmitter comprises a first spreading unit configured to multiply each of multiple data symbols with a first spreading code sequence of a first spreading factor; a compression and repetition unit configured to compress output signals of the first spreading unit in time domain and repeat the compressed signal L times (where L is a natural number greater than or equal to 2); a phase modulation unit configured to multiply the compressed and repeated signal with a user dependent phase and output a data block consisting of L sub-blocks; a second spreading unit configured to replicate the data block according to a second spreading factor and multiply each set of the replicated sub-blocks with a second spreading code sequence of the second spreading factor to produce a two-dimensionally spread signal; and a wireless transmission unit configured to transmit the two-dimensionally spread signal using a single-carrier transmission scheme.
    Type: Grant
    Filed: November 5, 2008
    Date of Patent: December 31, 2013
    Assignees: NTT DoCoMo, Inc., Agency for Science, Technology and Research
    Inventors: Hiroyuki Atarashi, Mamoru Sawahashi, Francois Po Shin Chin, Zhongding Lei, Xiaoming Peng, Ying-Chang Liang
  • Publication number: 20130336368
    Abstract: Disclosed herein is a receiver including: a first mixer adapted to mix satellite signals from first and second satellites and a first local oscillation signal so as to convert a carrier frequency of the satellite signals into a lower first intermediate frequency; a second mixer adapted to mix a satellite signal of the second satellite frequency-converted by the first mixer and a second local oscillation signal so as to convert the first intermediate frequency of the frequency-converted satellite signal from the second satellite into an even lower second intermediate frequency; and a first frequency divider adapted to generate the second local oscillation signal by dividing a frequency of the first local oscillation signal.
    Type: Application
    Filed: May 31, 2013
    Publication date: December 19, 2013
    Inventors: Daisuke Arima, Masayuki Katakura, Katsuyuki Tanaka
  • Publication number: 20130336367
    Abstract: Systems and methods for creating an alternative parallel wireless link communication in addition to wireless signals for a vehicle network. Embodiments of the present invention provide a spread spectrum transmission module that transmits a spread spectrum signal to a wayside equipment module in which such spread spectrum signal is reflected and communicated to a transmission module through an uplink communication. The uplink communication includes a first signal received from the wayside equipment module and the spread spectrum signal.
    Type: Application
    Filed: January 23, 2013
    Publication date: December 19, 2013
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Simone SODERI, Mario L. PAPINI
  • Patent number: 8599972
    Abstract: A method and apparatus removes bias from an initial signal-to-interference ratio (SIR). In an exemplary embodiment, an initial SIR calculator in an SIR processor calculates the initial SIR based on the signal received by the wireless receiver, while an average SIR calculator in the SIR processor generates an average SIR. Using the average SIR, a bias remover removes the bias from the initial SIR.
    Type: Grant
    Filed: June 16, 2004
    Date of Patent: December 3, 2013
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventors: Gregory Edward Bottomley, Carmela Cozzo
  • Patent number: 8599978
    Abstract: An interference elimination method provided herein includes: the ith transmitter of a group transmitters obtains an interference vector of each user, where: the interference vector of the kth user is Hkiwim; obtains at least L?N linear combinations for each user, wherein: the linear combination includes linear combinations of aligned interference vectors and linear combinations of N?Lk interference vectors, N is the number of receiving antennas of the user, and L is a sum of the signal flows of all users; the pre-coding vectors of all transmitters is obtained according to the linear combinations of all users; and the signals pre-coded using the pre-coding vectors are sent. Accordingly, a data transmitting apparatus is provided herein.
    Type: Grant
    Filed: November 10, 2011
    Date of Patent: December 3, 2013
    Assignee: Huawei Technologies Co., Ltd.
    Inventor: Sheng Liu
  • Patent number: 8588828
    Abstract: The base station includes: a first combiner which weights the BB signals received by first and second antenna elements by first and second weight coefficients and adds them; a second combiner which weights the BB signals received by third and fourth antenna elements by first and second weight coefficients and adds them; a third combiner which weights the BB signals added by the first and second combiners by third and fourth weight coefficients and adds them; a first processor which calculates such first and second weight coefficients that a combined polarization of the received signals of each antenna is orthogonal to a polarization of an interfering signal existing in the same direction as a desired signal; and a second processor which calculates such third and fourth coefficients that a null is formed in a direction different from the desired signal and in which an interfering signal exists.
    Type: Grant
    Filed: July 31, 2009
    Date of Patent: November 19, 2013
    Assignee: NEC Corporation
    Inventor: Masashi Hirabe
  • Patent number: 8588273
    Abstract: In a communication system, a timing-dependence cancelling module is included for cancelling timing-dependence of a transmission signal, so as to render a timing-dependent signal be capable of being utilized on communication systems. Besides, updating an echo cancelling parameter by applying an error difference variable and a data difference variable, or by directly decreasing a step-size coefficient, may also fulfill the purpose of reducing or eliminating timing dependence in a transmission signal of a communication system.
    Type: Grant
    Filed: November 24, 2011
    Date of Patent: November 19, 2013
    Assignee: Realtek Semiconductor Corp.
    Inventors: Liang-Wei Huang, Shieh-Hsing Kuo, Ta-Chin Tseng, Ting-Fa Yu
  • Patent number: 8588270
    Abstract: The invention includes a method for transmitting and detecting high speed Ultra Wideband pulses across a wireless interface. The transmitter includes a serializer and pulse generator. The receiver comprises a fixed delay line, multiplier, local serializer (with a sequence matching the transmitter), digital delay lines, low noise amplifier and logic fan-out buffer along with an array of D flip-flop pairs. Each flip-flop pair is enabled, at fixed time increments, to detect signals at a precise time; the timing is controlled by the pseudo-random sequence generated by the local serializer. A local tunable oscillator is controlled by detecting the phase change of the incoming signal and applying compensation to maintain the phase alignment and clock synchronization of the receiver to the clock reference of the transmitter. The invention uses a pair of pulses with a fixed delay and then relies on mixing the two to provide better noise immunity.
    Type: Grant
    Filed: December 4, 2012
    Date of Patent: November 19, 2013
    Assignee: University of South Florida
    Inventor: James L. Tucker
  • Patent number: 8587337
    Abstract: An embodiment of a technique to capture and locally synchronize data is disclosed. The technique includes receiving first and second signals through a first interface, and receiving a third signal through a second interface where the third signal is unsynchronized with respect to the second signal. The technique further includes detecting a first phase difference between the second and third signals, and generating a fourth signal in a manner so that a second phase difference between the fourth signal and one of the second or third signals is a function of the first phase difference. In addition, the technique includes storing a state of the first signal in response to the fourth signal, and thereafter supplying the stored state of the first signal to the second interface.
    Type: Grant
    Filed: January 19, 2010
    Date of Patent: November 19, 2013
    Assignee: Xilinx, Inc.
    Inventors: Schuyler E. Shimanek, Adam Elkins, Wayne E. Wennekamp
  • Patent number: 8588325
    Abstract: A communication system capable of achieving a high usage efficiency of frequencies without the need for cooperation of multiplexed users is disclosed. The communication system communicates over frequency channels set by dividing a frequency bandwidth assigned to the system and allows interference between channels by overlapping the adjacent frequency channels with each other in the frequency domain. A transmitting and receiving device, which transmits and receives a signal by allowing the interference between symbols at a waveform level for each channel to decrease the occupied bandwidth, is provided. The receiving device is provided with an Inter-Channel Interference (ICI) removal and Inter-Symbol Interference (ISI) compensation filter serving as either an ICI removal filter for removing the interference between channels or an ISI compensation filter for compensating the interference between symbols.
    Type: Grant
    Filed: March 12, 2008
    Date of Patent: November 19, 2013
    Assignee: NTT DoCoMo, Inc.
    Inventors: Anass Benjebbour, Takahiro Asai, Hitoshi Yoshino, Tatsuo Furuno, Tomoyuki Ooya
  • Patent number: 8582620
    Abstract: To enable transmission power control (outer loop control) considering changes (for example, changes in encoding gain and number of diffusions or the like) in durability for transmission error. The radio communication apparatus for controlling a target quality of a received signal used for the inner loop power control with outer loop power control. The radio communication apparatus comprises a detector operable to detect a change in durability for transmission error of received data and an update controller operable to execute a gradual update of the target quality for detection of high durability, when the detected durability is low.
    Type: Grant
    Filed: April 18, 2005
    Date of Patent: November 12, 2013
    Assignee: Fujitsu Limited
    Inventor: Atsushi Shinozaki
  • Publication number: 20130294482
    Abstract: The present invention relates to the field of communication technology, and provides a method and a device for eliminating interference in a mobile communication system. The method comprises: step 1: re-constructing signal estimation {circumflex over (d)}MAI+ISI of inter-symbol interference and multi-access interference in accordance with an output signal {circumflex over (d)}esb from an equalizer; and step 2: performing interference elimination on the inter-symbol interference and multi-access interference in an output signal êMF from a matched filter in accordance with the signal estimation {circumflex over (d)}MAI+ISI of inter-symbol interference and multi-access interference, to obtain signal estimation {circumflex over (d)}JD+IC with the interference eliminated. According to the present invention, it is able to eliminate the impact of an interference signal and improve the receptivity of a receiver for a useful signal.
    Type: Application
    Filed: November 3, 2011
    Publication date: November 7, 2013
    Applicant: ST-Ericsson Semiconductor (Beijing) Co., Ltd.
    Inventors: Zhixun Tang, Liang Zhuang
  • Publication number: 20130287064
    Abstract: The present invention relates to a wireless communication system, and discloses a method and a device for transmitting/receiving a downlink reference signal in a wireless communication system. The present invention provides a way for maintaining orthogonality of a reference signal between cells in a multi-cell operation.
    Type: Application
    Filed: January 5, 2012
    Publication date: October 31, 2013
    Applicant: LG ELECTRONICS INC.
    Inventors: Hanbyul Seo, Kijun Kim, Inkwon Seo
  • Patent number: 8571153
    Abstract: A method and apparatus for mitigating interference in a satellite signal receiver is described. The satellite signal receiver receives satellite signals from a plurality of satellites. In one example, a control signal is transmitted to the satellite signal receiver upon occurrence of data transmission from a wireless transceiver operating in proximity to the satellite signal receiver. Signal integration within the satellite signal receiver is gated in response to the control signal. In another example, one or more values of satellite signal samples are selected from a plurality of possible values. Signal integration within the satellite signal receiver is gated in response to a percentage of satellite signal samples taken over a predefined period exceeding a predefined threshold. In yet another example, a gain setting of an automatic gain control circuit within the satellite signal receiver is adjusted in response to detection of interference.
    Type: Grant
    Filed: April 14, 2010
    Date of Patent: October 29, 2013
    Assignee: Global Locate, Inc.
    Inventor: Charles Abraham
  • Patent number: 8571087
    Abstract: A baseband processing module according to the present invention includes a multi-path scanner module. The multi-path scanner module is operable to receive timing and scrambling code information regarding an expected multi-path signal component of a WCDMA signal. Then, the multi-path scanner module is operable to identify a plurality of multi-path signal components of the WCDMA signal by descrambling, despreading and correlating a known symbol pattern of/with a baseband RX signal within a search window. The multi-path scanner module is operable to determine timing information for the plurality of multi-path signal components of the WCDMA signal found within the search window and to pass this information to a coupled rake receiver combiner module.
    Type: Grant
    Filed: November 13, 2009
    Date of Patent: October 29, 2013
    Assignee: Broadcom Corporation
    Inventors: Mark David Hahm, Baoguo Yang
  • Patent number: 8565808
    Abstract: A transmission power determination system configured to control a transmission power of a radio signal transmitted by a small base station in a mobile communication network including a general base station forming a predetermined cell and the small base station forming a small cell smaller in size than the predetermined cell, the transmission power determination system comprising: a reception power acquisition unit configured to acquire a reception power of a radio signal from one of a different small base station or the general base station, which can be received by the small base station; a determination unit configured to determine one of the different small base station and the general base station which transmits the radio signal acquired by the reception power acquisition unit; a pathloss value calculation unit configured to calculate, when it is determined by the determination unit that the radio signal is transmitted from the different small base station, pathloss value between the different small bas
    Type: Grant
    Filed: August 5, 2011
    Date of Patent: October 22, 2013
    Assignee: NTT DoCoMo, Inc.
    Inventors: Hiroyuki Hosono, Takeshi Terayama, Takahiro Hayashi
  • Patent number: 8565287
    Abstract: A wireless system may receive a plurality of multipath signals from a plurality of transmitters and allocate per-cell modules for generating an interference suppressed signal from the multipath signals. Data symbols may be sequentially processed in the received multipath signals utilizing the per-cell modules and subtracting the processed symbols from a residual buffer storing the received multipath signals. Desired information received from one or more of the transmitters may be recovered utilizing the interference suppressed signal. Timing of the data symbols may be correlated utilizing a cell chip combiner. The data symbols may be descrambled utilizing conjugated scrambling codes associated with one of the plurality of transmitters. Orthogonal variable spreading factor (OVSF) codes may be generated utilizing a Walsh transform on the data symbols. Power levels of the OVSF codes may be estimated and estimated signals may be generated based on the OVSF codes and the estimated power levels.
    Type: Grant
    Filed: October 8, 2009
    Date of Patent: October 22, 2013
    Assignee: Broadcom Corporation
    Inventors: Mark Hahm, Wei Luo, Bin Liu, Jun Wu, Severine Catreux-Erceg, Shuangquan Wang
  • Patent number: 8560028
    Abstract: The present invention is directed to an antenna system. The antenna system may include a first antenna and a second antenna. The antenna system may further include a first LRU connected to the first antenna, and a second LRU connected to the second antenna. The antenna system may further include a router, said router being connected to the first LRU, the second LRU and a communication system, the communication system being remotely located from the antenna system. The router may be configured for receiving a plurality of concurrent (ex.—simultaneous) communication control inputs from the communication system and may selectively route the received communication control inputs to the LRUs. The LRUs may, based upon the received communication control inputs establish LRU settings for causing the antennas to transmit and/or receive communications in accordance with said communication control inputs.
    Type: Grant
    Filed: July 23, 2010
    Date of Patent: October 15, 2013
    Assignee: Rockwell Collins, Inc.
    Inventor: Mark A. Mulbrook
  • Publication number: 20130266043
    Abstract: A method of detecting a transmission. The method comprises: measuring, from a first portion of a received spread-spectrum signal, a first code-phase of a spreading-code; measuring, from a second portion of the signal, a second code-phase of the spreading-code; comparing the first and second code-phases; and detecting whether the transmission is present according to the result of the comparison. Also disclosed are corresponding methods and apparatus for transmission and reception of signals.
    Type: Application
    Filed: December 21, 2011
    Publication date: October 10, 2013
    Applicant: enModus Limited
    Inventor: Philip Young
  • Patent number: 8553791
    Abstract: In general, the subject matter described in this specification can be embodied in methods, systems, and program products for identifying data that is designated for wireless transmission to a remote computing device. A digital signal that encodes the data for transmission across a band of radio frequency channels is generated. Multiple radio frequency channels in the band that are available are determined. The digital signal is filtered to substantially reduce a power level of the digital signal at frequencies that correspond to channels in the band that have not been determined to be available. The filtered digital signal is converted to an analog signal. The analog signal is provided to an analog transmitter that isolates the band of channels to generate an isolated analog signal and that wirelessly transmits the isolated analog signal over the multiple available channels using one or more antennas.
    Type: Grant
    Filed: August 28, 2012
    Date of Patent: October 8, 2013
    Assignee: Google Inc.
    Inventors: E. Daniel McCloskey, C. Philip Gossett
  • Patent number: 8548029
    Abstract: The present invention relates to a method and apparatus for monitoring an antenna system comprising at least two antenna branches providing antenna diversity. At least a first signal branch measure and a second signal branch measure are repeatedly generated in response to a first signal branch and a second signal branch received by a respective one of the at least two antenna branches, thus generating a first plurality of second signal branch measure values in a manner so that the first and second pluralities reflect the quality of the first and second signal branches, respectively, at different points in time. The first and second pluralities are analysed in order to distinguish any differences in the performance of the first and second antenna branches.
    Type: Grant
    Filed: December 11, 2006
    Date of Patent: October 1, 2013
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventor: Stefan Willgert
  • Patent number: 8548107
    Abstract: A method for detecting multi-user signals including conducting a first energy burst detection detecting a first plurality of user signals as a first energy burst, attempting to decode a user signal from the first plurality of signals within the first energy burst, cancelling out a first user signal from the first energy burst if the first user signal is successfully decoded from the first energy burst, determining a second user signal to be discarded if the second user signal is not successfully decoded from the first energy burst, conducting a second energy burst detection detecting a second plurality of signals as a second burst, and iteratively cancelling out the first user signal successfully decoded from the first energy burst from the second energy burst, wherein the second energy burst detection is conducted when all user signals within the first energy burst are either cancelled out or determined to be discarded.
    Type: Grant
    Filed: January 25, 2010
    Date of Patent: October 1, 2013
    Assignee: Comtech Mobile Datacom Corporation
    Inventors: Richard Candell, Paul Ebert, John Fossaceca, Greg Handermann, Mark Holland, Lajuana Johnson, Bruce L. McKinley, Bo Wang, Ralph Eugene Crenshaw
  • Publication number: 20130243041
    Abstract: A method for estimating a scrambling code used on an uplink of a WCDMA system. The scrambling code is obtained from a Gold code, sum of a first specific M-sequence of the user and of a second M-sequence known from the receiver. After sampling of the signal received at the chip frequency of the scrambling code the successive samples are subject to a differential treatment and the sequence of differential values is multiplied by the second M-sequence. The observables thereby obtained are decoded with the aid of a belief propagation iterative decoding. The decoded values then serve to determine the content of the shift register of the generator of the first M-sequence. One then deduces therefrom the Gold code and an estimation of the scrambling code, ?.
    Type: Application
    Filed: March 11, 2013
    Publication date: September 19, 2013
    Applicant: COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENE ALT
    Inventor: Mathieu BOUVIER DES NOES
  • Patent number: 8537928
    Abstract: Methods and systems that enable the determination of accurate channel estimates by measuring only power values of pilot signal transmissions at a receiver are described. Various measurement procedures that are based on average power measurements or short term, per-symbol measurements can be employed. Furthermore, procedures utilizing adaptive pilots generated with receiver feedback and deterministic pilots generated without receiver feedback are also described.
    Type: Grant
    Filed: October 8, 2010
    Date of Patent: September 17, 2013
    Assignee: NEC Laboratories America, Inc.
    Inventors: Mohammad A. Khojastepour, Karthikeyan Sundaresan, Sampath Rangarajan
  • Publication number: 20130235906
    Abstract: An electronic device may contain clock circuits, transmitters, and other circuits that serve as sources of noise signals. The noise signals may be characterized by a noise spectrum. The noise spectrum produced by a noise source can be adjusted by adjusting spread spectrum clock circuitry in a clock circuit, by adjusting data scrambling circuitry in a transmitter circuit, or by making other dynamic adjustments to the circuitry of the electronic device. During operation of the electronic device, sensitive circuitry in the device such as wireless receiver circuitry may be adversely affected by the presence of noise from a noise source in the device. Based on information such as which receiver bands and/or channels are being actively received and target sensitivity levels for the receiver circuitry, control circuitry within the electronic device can determine in real time how to minimize interference between the noise source and the wireless receiver circuitry.
    Type: Application
    Filed: March 9, 2012
    Publication date: September 12, 2013
    Inventors: Moon Jung Kim, Geertjan Joordens, Paolo Sacchetto, Wonjae Choi, Altan N. Yazar, Jaydeep V. Ranade
  • Patent number: 8532685
    Abstract: A base station of the present invention includes: first and second antenna elements that have polarization characteristics orthogonal to each other; a first converter that converts a received signal of the first antenna element into a baseband signal; a first multiplier that weights the baseband signal converted by the first converter by multiplying a first weight coefficient; a second converter that converts a received signal of the second antenna element into a baseband signal; a second multiplier that weights the baseband signal converted by the second converter by multiplying a second weight coefficient; an adder that adds the baseband signals weighted by the first and second multipliers and outputs the sum; and, a signal processor that calculates the first and second coefficients by MMSE such that the combined polarization of the received signals of the first and second antenna elements will be orthogonal to the polarization of an interference signal.
    Type: Grant
    Filed: June 19, 2009
    Date of Patent: September 10, 2013
    Assignee: NEC Corporation
    Inventor: Masashi Hirabe
  • Patent number: 8526412
    Abstract: Techniques for multiplexing multiple data streams using frequency division multiplexing (FDM) in an OFDM system are described. M disjoint “interlaces” are formed with U usable subbands. Each interlace is a different set of S subbands, where U=M·S. The subbands for each interlace are interlaced with the subbands for each of the other M?1 interlaces. M slots may be defined for each symbol period and assigned slot indices 1 through M. The slot indices may be mapped to interlaces such that (1) frequency diversity is achieved for each slot index and (2) the interlaces used for pilot transmission have varying distances to the interlaces used for each slot index, which improves channel estimation performance. Each data stream may be processed as data packets of a fixed size, and different numbers of slots may be used for each data packet depending on the coding and modulation scheme used for the data packet.
    Type: Grant
    Filed: October 18, 2004
    Date of Patent: September 3, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Rajiv Vijayan, Gordon Kent Walker, Raghuraman Krishnamoorthi, Murali R. Chari
  • Patent number: 8520493
    Abstract: A method for transmitting messages from first units of an integrated circuit to at least one second unit of the integrated circuit. The first units generate first digital messages and transform them into second digital messages obtained by application of an orthogonal or quasi-orthogonal transformation to the first messages. The second messages of the first units are added up and transmitted to the second unit.
    Type: Grant
    Filed: September 17, 2009
    Date of Patent: August 27, 2013
    Assignee: STMicroelectronics (Grenoble) SAS
    Inventor: Abdelaziz Goulahsen
  • Patent number: 8503591
    Abstract: A method for suppressing interference in a wireless communication is provided. The method comprises receiving a burst of symbols, generating a plurality of timing hypotheses for the burst of symbols, and calculating, for each timing hypothesis, a plurality of weights for an interference suppression filter based upon a subset of the burst of symbols. The method further comprises, for each timing hypothesis, filtering the subset of the burst of symbols using the interference suppression filter with the corresponding plurality of weights, and selecting one of the plurality of timing hypotheses corresponding to a selection criteria. The method further comprises equalizing and decoding the filtered burst of symbols based upon the selected one of the plurality of timing hypotheses.
    Type: Grant
    Filed: August 19, 2008
    Date of Patent: August 6, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Divaydeep Sikri, Farrokh Abrishamkar, Michael McCloud
  • Patent number: 8503506
    Abstract: Aspects of a method and system for interference suppression in WCDMA systems may include one or more circuits that are operable to receive a plurality of multipath signals via one or more receiving antennas. A plurality of weighting factor values may be computed based on the received multipath signals. Estimated signals may be based on the weighting factor values. Residual signals may be generated based on received signals and the estimated signals. Addback signals may be generated based on the estimated signals and the residual signals. Updated estimated signals may be generated based on the addback signals and the weighting factor values. Incremental signals may be generated based on the updated estimated signals and addback signals. Updated residual signals may be generated based on the incremental signals and previous residual signals. The interference suppressed signals may be generated based on the updated residual signals and updated estimated signals.
    Type: Grant
    Filed: August 17, 2012
    Date of Patent: August 6, 2013
    Assignee: Broadcom Corporation
    Inventors: Mark Hahm, Wei Luo, Arkady Molev-Shteiman, Hongwei Kong, Xiao-Feng Qi, Li Fung Chang, Nelson Sollenberger