With Output Combining Patents (Class 455/137)
  • Patent number: 7596359
    Abstract: A receiving apparatus is for selecting and receiving a radio signal in a frame structure having an information body part including at least information body and an additional part including information for receiving field intensity measurement by using a plurality of antennas. The apparatus includes a controller that measures a receiving field intensity of not a first antenna which has received the information body in a transmission period of the additional part in a current frame but a second antenna, and measures a receiving field intensity of the first antenna in a transmission period of the information body part in the current frame, and if the receiving field intensity of the second antenna exceeds the receiving field intensity of the first antenna, selects and changes to the second antenna as the first antenna of a next frame.
    Type: Grant
    Filed: July 7, 2006
    Date of Patent: September 29, 2009
    Assignee: Olympus Corporation
    Inventors: Seiichiro Kimoto, Toshiaki Shigemori, Ayako Nagase, Manabu Fujita, Akira Matsui, Kazutaka Nakatsuchi
  • Patent number: 7580735
    Abstract: In a condenser microphone where a microphone capsule and an output module section are connected to each other via a microphone cord, strong electromagnetic waves generated from a cellular phone or the like are positively prevented from entering the output module section through the microphone cord. The condenser microphone in which a microphone capsule 10 and an output module section 20 are connected to each other via a microphone cord 30 composed of a twin-core shield covered wire, the microphone capsule 10 including a condenser microphone unit 12 and an impedance converter 13, the output module section 20 storing, in a shield case 21, a circuit board 22 including a voice output circuit, wherein a shield covered wire 33 of the microphone cord 30 is connected to the shield case 21, and the shield covered wire 33 is also connected to a ground circuit of the circuit board 22 via a high-frequency choke coil 51.
    Type: Grant
    Filed: May 16, 2005
    Date of Patent: August 25, 2009
    Assignee: Kabushiki Kaisha Audio-Technica
    Inventor: Hiroshi Akino
  • Patent number: 7573398
    Abstract: A communication system is presented. The system includes one or more transmitters configured to transmit a signal, where each of the signals generated by the one or more transmitters corresponds to a respective frequency. Further, the system includes a plurality of receiver front-ends configured to receive the signal transmitted by each of the one or more transmitters. The system also includes a plurality of remodulator modules configured to translate each of the received signals to a signal having a respective intermediate frequency. In addition, the system includes a combining module configured to combine each of the signals having respective intermediate frequencies to generate a single composite signal. Also, the system includes a single analog-to-digital converter configured to process the composite signal and generate a digital output. Additionally, the system includes a digital signal processor module configured to extract the signal transmitted by each of the one or more transmitters.
    Type: Grant
    Filed: June 29, 2005
    Date of Patent: August 11, 2009
    Assignee: General Electric Company
    Inventors: Ralph Thomas Hoctor, Richard Louis Zinser, Jr., Matthew George Grubis, Neal John Seidl
  • Patent number: 7558533
    Abstract: A receiver is described herein that is capable of receiving and processing a radio signal and further capable of using interpolation to initialize receiver parameters when there is a change in at least one delay associated with the received radio signal or when there is at least one new correlator position. For instance, the receiver parameters that can be initialized include: (1) channel coefficients; (2) AFC parameters; (3) tracking parameters; (4) noise statistics (noise correlations); (5) signal statistics (channel coefficient correlations); (6) data statistics (despread values or chip samples); or (7) combining weights.
    Type: Grant
    Filed: November 7, 2007
    Date of Patent: July 7, 2009
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventors: Carmela Cozzo, Gregory Bottomley, Rajaram Ramesh
  • Patent number: 7535969
    Abstract: A system and method for generating transmit weighting values for signal weighting that may be used in various transmitter and receiver structures is disclosed herein. The weighting values are determined as a function of frequency based upon a state of a communication channel and the transmission mode of the signal. In variations, weighting of the weighted signal that is transmitted through each of a plurality of antennas is carried out with one of a corresponding plurality of transmit antenna spatial weights. In these variations, a search may be conducted over various combinations of transmit weighting values and transmit antenna spatial weights in order to find a weight combination that optimizes a performance measure such as the output signal-to-noise ratio, the output bit error rate or the output packet error rate.
    Type: Grant
    Filed: July 29, 2004
    Date of Patent: May 19, 2009
    Assignee: Broadcom Corporation
    Inventors: Severine Catreux, Vinko Erceg, Pieter Roux, Pieter van Rooyen, Jack Winters
  • Patent number: 7522894
    Abstract: A radio receiving apparatus includes two receiving antennas, two upstream RF amplifiers, a SAW filter having two input IDTs and an output IDT, a downstream RF amplifier, and a detector circuit. The antennas are connected to the respective input IDTs via the respective upstream RF amplifiers. The detector circuit is connected via the downstream RF amplifier to the output IDT, which receives a signal from each of the two input IDTs. The distances from the center of the output IDT to the centers of the input IDTs differ from one another. The SAW filter functions as two band-pass filters, two delay circuits connected to the respective band-pass filters, and a combiner circuit for combining the outputs from the delay circuits.
    Type: Grant
    Filed: January 8, 2004
    Date of Patent: April 21, 2009
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Akira Kato, Takashi Kawabata
  • Patent number: 7519128
    Abstract: In a wireless transmitting device which performs transmission by an OFDM using a plurality of subcarriers orthogonal to each other, a plurality of preambles to which a plurality of different subcarrier groups selected from a plurality of subcarriers within an OFDM signal band are allocated are transmitted by using a plurality of transmit antennas, and data is transmitted by using the antennas after the preambles are transmitted.
    Type: Grant
    Filed: April 1, 2008
    Date of Patent: April 14, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Ichiro Seto, Tsuguhide Aoki, Hiroshi Yoshida
  • Patent number: 7515892
    Abstract: Disclosed is an operation method of a base station antenna system, which includes receiving signals from at least two antennas to which a mono-pulse scheme has been applied; operating sum channel weight vectors for increasing a gain of signals incident to a specific direction and difference channel weight vectors for causing a gain of signals incident to a specific direction to be zero; applying the sum channel weight vectors and the difference channel weight vectors to the received signals, and outputting predetermined signals; and obtaining beam patterns of a sum channel and a difference channel, to which the weight vectors have been applied, by means of a direction of interest, calculating a mono-pulse ratio by means of the beam patterns, and estimating the direction of a mobile station by means of the mono-pulse ratio, and output of the sum channel and output of the difference channel to which the weight vectors have been applied.
    Type: Grant
    Filed: December 28, 2005
    Date of Patent: April 7, 2009
    Assignee: Samsung Electronics Co., Ltd
    Inventors: Sung-Hoon Moon, Jae-Young Jang, Chung-Kyun Ham
  • Patent number: 7512083
    Abstract: A single chip integrated circuit wireless data processor demodulates N separate data signals from M separate antennas simultaneously. The multi-antenna processor can be coupled to a baseband processor on the IC, so that it responds to changing channel conditions between two access points, and selectively kicks in if there is noise, interference, frequency fading, a need for an enhanced data rate, a need for an increased operating range, etc. to improve a performance of the baseband processor.
    Type: Grant
    Filed: April 7, 2004
    Date of Patent: March 31, 2009
    Inventor: Shaolin Li
  • Patent number: 7512419
    Abstract: A wireless distribution system includes a number of remote units distributed in a coverage area to receive wireless signals and to provide the signals through the distribution system to input ports of an expansion unit where the signals are combined, detectors operatively connected to one or more of the plurality of input ports to determine the presence of information carrying signals at the input ports, a number of selection circuits to select signals in which information has been detected, and a node to combine the selected signals.
    Type: Grant
    Filed: April 21, 2006
    Date of Patent: March 31, 2009
    Assignee: ADC Telecommunications, Inc.
    Inventor: Jeff Solum
  • Patent number: 7512198
    Abstract: A communication system employing site diversity combing to increase link availability includes at least two receivers at receive sites within a single downlink beam separated by enough distance to provide decorrelation of weather phenomena—such as rain fade outages. A signal transmits digital symbols to all the receivers and may use bandwidth efficient modulation with forward error correction coding. Sampled symbol values for each codeword are produced at each receiver, which are connected by one or more ground links so that all data can be collected at one site. At least two different soft-decision computation modules translate the sampled symbol values from the different receivers into different sets of soft-decision values—which may be log-likelihood-ratio (LLR) values reflecting the probability value for each bit of the codeword—that are digitally synchronized and combined for use by a decoder. The technique thus avoids disadvantages of either coherent waveform combining or BER-based digital switching.
    Type: Grant
    Filed: June 24, 2005
    Date of Patent: March 31, 2009
    Assignee: The Boeing Company
    Inventors: Andrew L. Strodtbeck, Jennifer Vollbrecht, Todd G. Ellenberger
  • Patent number: 7508864
    Abstract: Briefly, a wireless communication device having a receiver includes a pilot signal interference canceller and a linear interference suppressor is provided. The pilot signal interference canceller and the linear interference suppressor jointly operate to cancel a pilot signal interference and other interference which are part of a received signal. A method for jointly cancel the interference by the pilot signal interference canceller and the linear interference suppressor is also provided.
    Type: Grant
    Filed: February 14, 2005
    Date of Patent: March 24, 2009
    Assignee: Intel Corporation
    Inventors: Shimon Moshavi, Daniel Yellin
  • Publication number: 20090075610
    Abstract: Third-order intermodulation products (IM3) are attenuated in RF receivers by providing a typical main signal path and a parallel auxiliary signal path in which the IM3 products are accentuated, and the output from the main signal path is adaptively filtered to attenuate the IM3 products. In one embodiment, a multirate filter bank (MRFB) with asymmetric analysis and synthesis sections is used to detect and isolate the IM3 products. In another embodiment an analog nonlinear term generator is placed at the front of the auxiliary signal path. The analog nonlinear term generator takes advantage of the nonlinearities of a differential MOSFET circuit and a multiplier to extract the IM3 products in the RF input signal. The outputs of the main signal path and the auxiliary signal path are inputs to a complex least mean squares filter to attenuate the IM3 products in the resulting signal.
    Type: Application
    Filed: May 21, 2007
    Publication date: March 19, 2009
    Applicant: California Institute of Technology
    Inventors: Edward Keehr, Seyed Ali Hajimiri
  • Patent number: 7502355
    Abstract: A radio frequency (RF) power combiner for connecting multiple base transceiver stations with one antenna assembly includes at least one combining device coupled to at least two base transceiver stations for combining signals generated thereby into a combined signal for being transmitted by the antenna assembly. At least one frequency selective RF power detector is coupled to one of the signals generated from one of the base transceiver stations for generating an output indicating whether the signal at a predetermined frequency is present. A logic control module is coupled to the frequency selective RF power detector for generating a control signal in response to the output of the detector. An oscillator is coupled to the logic control module for generating a carrier signal at the predetermined frequency for the combined signal in response to the control signal.
    Type: Grant
    Filed: February 22, 2006
    Date of Patent: March 10, 2009
    Assignee: Cisco Technology, Inc.
    Inventors: George Bednekoff, Philip B. Davis, Michael A. Hinz, Viet Huynh, Mitchell K. Johnson
  • Patent number: 7496129
    Abstract: Methods and systems consistent with this invention receive a plurality of transmitted signals in a receiver having a plurality of receive elements, wherein each transmitted signal has a different spatial location. Such methods and systems receive the plurality of transmitted signals at the plurality of receive elements to form a plurality of receive element signals, form a combined signal derived from the plurality of receive element signals, and detect each of the plurality of transmitted signals from the combined signal by its different spatial location. To achieve this, methods and systems consistent with this invention generate a plurality of arbitrary phase modulation signals, and phase modulate each of the plurality of receive element signals with a different one of the phase modulation signals to form a plurality of phase modulated signals.
    Type: Grant
    Filed: July 31, 2007
    Date of Patent: February 24, 2009
    Assignee: Greenwich Technologies Associates
    Inventor: Carl M. Elam
  • Publication number: 20090047999
    Abstract: A method and system for beamforming communication in a wireless communication system that includes a wireless initiator and a wireless responder is provided. A communication channel matrix is estimated at the responder based on training symbols from the initiator. The estimated channel matrix is then deconstructed into certain components, and the matrix components are quantized for feedback to the initiator for channel matrix reconstruction and beamforming communication.
    Type: Application
    Filed: August 16, 2007
    Publication date: February 19, 2009
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Pengfei Xia, Huaning Niu, Chiu Ngo
  • Patent number: 7466975
    Abstract: Global Positioning System (GPS) and non GPS position finder, emergency, multiple input multiple output (MIMO), multimode, spread spectrum, code division multiple access (CDMA), Global Mobile System or Global System Mobile (GSM) and orthogonal frequency division multiplex (OFDM) communication systems. Position finder and emergency communication multiple input multiple output (MIMO) system and a receiver having multiple inputs for reception and demodulation of position finder signals to position finder baseband signals. A processor for processing position finder signals with a signal containing an emergency number. A processors for processing signals to provide cross-correlated shaped in-phase and quadrature-phase baseband signals, spread spectrum and OFDM baseband signals. A control unit for control and selection of one of the jointly processed signals and a selector for providing the selected signal to a modulator.
    Type: Grant
    Filed: April 28, 2006
    Date of Patent: December 16, 2008
    Inventor: Kamilo Feher
  • Patent number: 7453965
    Abstract: Input signals of each frame are encoded by mapping the signals onto a coordinate system dictated by the symbols of the previous frame, and symbols from a constellation are selected based on the results of such mapping. Received signals are detected by preprocessing the signals detected at each antenna with signals detected by the antenna at the immediately previous frame, and then applied to a maximum likelihood detector circuit, followed by an inverse mapping circuit.
    Type: Grant
    Filed: January 16, 2007
    Date of Patent: November 18, 2008
    Assignee: AT&T Corp.
    Inventors: Hamid Jafarkhani, Vahid Tarokh
  • Patent number: 7433660
    Abstract: An iterative multistage detection system and method for orthogonally multiplexing K channels onto a signal processing chain using N orthogonal sequences of length N. The K channels include a first set of N channels and a second set of M channels (the M channels being separate and distinct from the N channels), where K=N+M. In a first iteration, interference from the first set of N channels imparted on the second set of M channels is removed from the multiplexed signal, thereby enabling the symbol values associated with the second set of M channels to be reliably estimated. In a second iteration, interference from the second set of M channels imparted on the first set of N channels is removed from the first set of N channels, thereby enabling the symbol values associated with the first set of N channels to be reliably estimated.
    Type: Grant
    Filed: April 2, 2007
    Date of Patent: October 7, 2008
    Assignee: Broadcom Corporation
    Inventors: Pieter van Rooyen, Danie van Wyk
  • Patent number: 7433414
    Abstract: A receiver sets weights for an antenna array according to a series of algorithms including an energy algorithm, a least squares algorithm and a least mean square algorithm.
    Type: Grant
    Filed: December 21, 2004
    Date of Patent: October 7, 2008
    Assignee: Sigma Designs, Inc.
    Inventors: Hung C. Nguyen, Jifeng Geng, Ruoyang Lu, Catherine A. French
  • Patent number: 7433384
    Abstract: Method and apparatus to compute the combiner coefficients for wireless communication systems for a space-time solution. One embodiment trains the weights on a signal known a priori that is time multiplexed with other signals, such as a pilot signal in a High Data Rate, HDR, system, wherein the signal is transmitted at full power. A Minimizing Mean Square Error, MMSE, approach is applied allowing weight combining on a per path basis. The weights are calculated as a function of a noise correlation matrix and spatial signature per path. The noise correlation matrix is determined from an autocorrelation matrix of the received signal. In one embodiment, the MMSE approach is applied to a non-time gated pilot signal.
    Type: Grant
    Filed: January 9, 2006
    Date of Patent: October 7, 2008
    Assignee: QUALCOMM Incorporated
    Inventors: John Edward Smee, Nagabhushana Sindhushayana
  • Patent number: 7433659
    Abstract: An iterative multistage detection system and method for orthogonally multiplexing K channels onto a signal processing chain using N orthogonal sequences of length N. The K channels include a first set of N channels and a second set of M channels (the M channels being separate and distinct from the N channels), where K=N+M. In a first iteration, interference from the first set of N channels imparted on the second set of M channels is removed from the multiplexed signal, thereby enabling the symbol values associated with the second set of M channels to be reliably estimated. In a second iteration, interference from the second set of M channels imparted on the first set of N channels is removed from the first set of N channels, thereby enabling the symbol values associated with the first set of N channels to be reliably estimated.
    Type: Grant
    Filed: April 2, 2007
    Date of Patent: October 7, 2008
    Assignee: Broadcom Corporation
    Inventors: Pieter van Rooyen, Danie van Wyk
  • Patent number: 7430190
    Abstract: A wireless communication system configured for the efficient allocation of resources is provided. The wireless communication system can include a transmit system having a first set of one or more antennas each configured to transmit a data signal over a region to a receive system having a second set of two or more antennas each configured to receive the transmitted data signal. The transmit system can be configured to adjust a transmission parameter of a data signal based on a level of signal fading in the region to sustain a target bit rate, adjust a power and a bit rate at which a data signal is transmitted based on the level of signal fading in the region and select a subset of antennas within the first set of antennas to be used to transmit a data signal based on the level of signal fading in the region.
    Type: Grant
    Filed: January 24, 2005
    Date of Patent: September 30, 2008
    Assignee: The Regents of the University of California
    Inventors: Wenjun Luo, Magda El Zarki, Lei Zan
  • Publication number: 20080220734
    Abstract: The present invention discloses a log function generator module device that is adapted to receive substantially simultaneously a plurality of signals at a plurality of respective communication links. The device includes a plurality of sets of logarithmic, a plurality of substantially linear amplifiers, a plurality of negative-value-eliminator (NVE) modules, a plurality of preliminary adders, a plurality of limiters and one final adder all of which are associated with each other a manner such that the output of the final adder is a final signal that substantially corresponds to a logarithm of the sum of the square of each of the received signals, thereby providing a received signal strength indication (RSSI) of the plurality of received signals.
    Type: Application
    Filed: March 5, 2007
    Publication date: September 11, 2008
    Inventor: Hanan Cohen
  • Patent number: 7412218
    Abstract: An iterative multistage detection system and method for orthogonally multiplexing K channels onto a signal processing chain using N orthogonal sequences of length N. The K channels include a first set of N channels and a second set of M channels (the M channels being separate and distinct from the N channels), where K=N+M. In a first iteration, interference from the first set of N channels imparted on the second set of M channels is removed from the multiplexed signal, thereby enabling the symbol values associated with the second set of M channels to be reliably estimated. In a second iteration, interference from the second set of M channels imparted on the first set of N channels is removed from the first set of N channels, thereby enabling the symbol values associated with the first set of N channels to be reliably estimated.
    Type: Grant
    Filed: April 2, 2007
    Date of Patent: August 12, 2008
    Assignee: Broadcom Corporation
    Inventors: Pieter van Rooyen, Danie van Wyk
  • Patent number: 7409193
    Abstract: Systems and methods related to amplifier systems which use a predistortion subsystem to compensate for expected distortions in the system output signal. A signal processing subsystem receives an input signal and decomposes the input signal into multiple components. Each signal component is received by a predistortion subsystem which applies a predistortion modification to the component. The predistortion modification may be a phase modification, a magnitude modification, or a combination of both and is applied by adjusting the phase of the fragment. The predistorted component is then separately processed by the signal processing subsystem. The processing may take the form of phase modulation and amplification. The phase modulated and amplified components are then recombined to arrive at an amplitude and phase modulated and amplified output signal. The predistortion modification is applied to the components to compensate for distortions introduced in the signal by the signal processing subsystem.
    Type: Grant
    Filed: August 13, 2003
    Date of Patent: August 5, 2008
    Assignee: Zarbana Digital Fund LLC
    Inventor: Aryan Saėd
  • Patent number: 7403798
    Abstract: Antennas in an entire radio base station system are divided into two antenna groups so that each group has antennas in the number that allows convergence of reception directivity using a reference signal length. Reception weight vector calculators (112, 212) corresponding to respective antenna groups perform adaptive array processings, and corresponding array outputs are provided to a maximum ratio combining circuit (18). The maximum ratio combining circuit (18) performs maximum ratio combining of the array outputs corresponding to two antenna groups, based on weight information output from the reception weight vector calculators (112, 212).
    Type: Grant
    Filed: August 13, 2001
    Date of Patent: July 22, 2008
    Assignee: Sanyo Electric Co., Ltd.
    Inventor: Yoshiharu Doi
  • Patent number: 7400867
    Abstract: A radio broadcast receiver is provided which reduces the degradation in quality of diversity-received signals. When a difference in level between a reception signal of a main antenna and a reception signal of a sub antenna is less than a predetermined threshold value, and when a difference in phase between the reception signal of the main antenna and the reception signal of the sub antenna exceeds another predetermined threshold value, a combination ratio of a combiner for combining outputs of a main tuner and of a sub tuner is set to 1:1, where in-phase combination type diversity is carried out. In other cases, the combination ratio of the combiner is switched between 1:0 and 0:1 depending on the occurrence of a multipath, where selection diversity is carried out.
    Type: Grant
    Filed: October 24, 2005
    Date of Patent: July 15, 2008
    Assignee: Alpine Electronics, Inc.
    Inventor: Yoshitsugu Gamo
  • Patent number: 7398067
    Abstract: Embodiment of the invention provides a receiving device having an intermediate frequency section to produce first and second intermediate frequency signals based on first and second received radio frequency signals, such that said intermediate frequency signals are combinable to be jointly processed. The first intermediate frequency signal is antipodal to the second intermediate frequency signal. Embodiment of the invention further provides at least one common sub-circuit to process at least one combined intermediate frequency signal which is based on components of first and second intermediate frequency signals.
    Type: Grant
    Filed: March 17, 2005
    Date of Patent: July 8, 2008
    Assignee: Intel Corporation
    Inventor: Guy Wolf
  • Patent number: 7394858
    Abstract: In an orthogonal frequency division multiplexed (OFDM) system, a transmitter and/or receiver communicate separate data streams on non-orthogonal spatial channels. Each spatial channel may use the same set of OFDM subcarriers and may take advantage of the multipath characteristics of the spatial channel allowing the communication of additional data without an increase in frequency bandwidth. Space-frequency subcarrier modulation assignments may be dynamically assigned on a per subcarrier basis as well as a per spatial channel basis to help maximize the data-carrying capacity of the channel. In some embodiments, each of the spatial channels may be associated with one of a plurality of spatially diverse antennas. In other embodiments, beamforming may be performed to allow the transmission and/or reception of signals within the spatial channels.
    Type: Grant
    Filed: December 29, 2003
    Date of Patent: July 1, 2008
    Assignee: Intel Corporation
    Inventors: John S. Sadowsky, Minnie Ho, Sumeet Sandhu, Alexander A. Maltsev, Eric A. Jacobsen, Ali S Sadri
  • Publication number: 20080153440
    Abstract: A method and apparatus for receiving data using multiple antennas in a communication system are provided. A received signal-combining scheme is determined according to the strength of an interference signal included in the signals received from the antennas. The signals received from the antennas are combined according to the determined received signal-combining scheme. In this manner, the method and apparatus adaptively use a received data-combining scheme according to the channel condition, thereby ensuring optimal reception performance.
    Type: Application
    Filed: December 20, 2007
    Publication date: June 26, 2008
    Applicant: SAMSUNG ELECTRONICS CO., LTD
    Inventors: Jong-Hun Rhee, Min-Goo Kim, Young-Mo Gu
  • Patent number: 7392025
    Abstract: An iterative multistage detection system and method for orthogonally multiplexing K channels onto a signal processing chain using N orthogonal sequences of length N. The K channels include a first set of N channels and a second set of M channels (the M channels being separate and distinct from the N channels), where K=N+M. In a first iteration, interference from the first set of N channels imparted on the second set of M channels is removed from the multiplexed signal, thereby enabling the symbol values associated with the second set of M channels to be reliably estimated. In a second iteration, interference from the second set of M channels imparted on the first set of N channels is removed from the first set of N channels, thereby enabling the symbol values associated with the first set of N channels to be reliably estimated.
    Type: Grant
    Filed: April 2, 2007
    Date of Patent: June 24, 2008
    Assignee: Broadcom Corporation
    Inventors: Pieter van Rooyen, Danie van Wyk
  • Patent number: 7386029
    Abstract: At noise component addition section 105, a noise equivalent value equivalent in size to noise component is calculated using a constant which is dependent on a difference of spreading factors between a common pilot channel and packet channels, and at correlation matrix and correlation vector calculation section 106, the noise equivalent value is added to diagonal elements of an autocorrelation matrix. At weight calculation section 107, an optimal weight is calculated using the autocorrelation matrix whose diagonal elements have been added the noise equivalent value, and at adaptive equalization section 108, equalization of reception signal is carried out. Thereby, noise enhancement produced in the packet channels after the equalization due to the difference between the spreading factor of the common pilot channel and the spreading factor of the packet channels can be reduced.
    Type: Grant
    Filed: May 26, 2004
    Date of Patent: June 10, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masayuki Hoshino, Takenobu Arima
  • Patent number: 7369834
    Abstract: An impedance-matched IQ network includes a phase shift circuit and a back termination. The phase shift circuit includes an in-phase mixer port for receiving the in-phase signal, a quadrature-phase mixer port for receiving the quadrature phase signal, a termination port, and an output port. The back termination is coupled to the termination port of the phase shift circuit, the back termination having an impedance value substantially equal to the characteristic impedance of the phase shift circuit at the termination port.
    Type: Grant
    Filed: October 9, 2003
    Date of Patent: May 6, 2008
    Assignee: RF Magic, Inc.
    Inventor: Keith P. Bargroff
  • Patent number: 7363016
    Abstract: A communication system comprises a first signal adjusting unit for amplifying a first signal received by a first antenna; a second signal adjusting unit for amplifying and phase-shifting a second signal received by a second antenna to generate a phase-shifted signal; first and second mixers for respectively mixing signals generated by said first and second signal adjusting units to generate respective first and second intermediate frequency signals; a signal combiner for generating an output signal provided to a demodulator, the output signal comprising at least one of the first intermediate frequency signal and/or the second intermediate frequency signal; and a phase detector for extracting phase information from the signals generated by the first and second signal adjusting units.
    Type: Grant
    Filed: March 26, 2003
    Date of Patent: April 22, 2008
    Assignee: LG Electronics Inc.
    Inventor: One-Pil Lee
  • Publication number: 20080057885
    Abstract: A radio receiver front-end includes first and second RF receiver sections and an RF combining module. The first RF receiver section is coupled to receive an inbound RF signal and provide to a first representation of the inbound RF signal, wherein the inbound RF signal includes a desired signal component and an undesired signal component. The second RF receiver section is coupled to receive the inbound RF signal and to provide a second representation of the inbound RF signal. The RF combining module is coupled to combine the first and second representations of the inbound RF signal to produce a desired RF signal, wherein the desired RF signal includes the desired signal component and an attenuated representation of the undesired signal component.
    Type: Application
    Filed: August 30, 2006
    Publication date: March 6, 2008
    Applicant: Broadcom Corporation, a California Corporation
    Inventor: Ahmadreza (Reza) Rofougaran
  • Patent number: 7340016
    Abstract: A multi-branch receiver comprises a plurality of signal branches including branch filters to filter respective branch input signals and to produce corresponding branch output signals, a combiner to combine the branch output signals to produce a combined baseband signal, a pre-filter to filter the combined baseband signal to produce a received signal with minimum phase channel characteristics, and an equalizer to generate an estimate of a data sequence contained in the received signal.
    Type: Grant
    Filed: July 12, 2004
    Date of Patent: March 4, 2008
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventor: Dennis Hui
  • Patent number: 7339979
    Abstract: Wireless communication systems and methods are provided that a) enable progressive beamforming with antenna arrays and subarrays, b) provide current and delayed versions of data-carrying signals, and c) provide time-of-arrival of data-carrying signals. The progressive beamforming substantially reduces computational complexity. The current and delayed versions of data-carrying signals facilitate optimization of spatial information and optimization of information from non-coherent delays (which are delays beyond the handling capability of a system's modulation). The time-of-arrival information is used to facilitate a single matrix inversion which substantially reduces the complexity of conventional beamforming computations.
    Type: Grant
    Filed: January 23, 2004
    Date of Patent: March 4, 2008
    Assignee: Calamp Corp.
    Inventor: Kris Kelkar
  • Publication number: 20080032648
    Abstract: A wideband combiner includes a core amplifier for receiving first and second pairs of differential input signals and providing a single pair of differential output signals. The pair of differential output signals are a combination of the first and second pair of differential input signals and a signal gain is implemented between the received first and second pairs of differential input signals and the single pair of differential output signals. The core amplifier is configured to provide a gain value between the first and second pairs of differential input signals and the single pair of differential output signals. The signal gain is substantially constant across the frequency bandwidth of the core amplifier. A bandwidth peaking network is coupled to the core amplifier and includes (a) a first coil and a first resistor connected in series and (b) a second coil and a second resistor connected in series.
    Type: Application
    Filed: August 15, 2006
    Publication date: February 7, 2008
    Inventor: Michael A. Wyatt
  • Patent number: 7315730
    Abstract: An architecture for a receiver front end utilizes a dual output low noise amplifier (102) driving separate, fixed preselectors (104, 106) coupled to a transformer (108) to generate a single ended output (113). A pair of blocks coupled in series provides a dual band output. Additional pairs of blocks (201, 203) can be cascaded in parallel to provide additional frequency bands of operation. The front end architecture of the present invention provides switchless multi-band operation to a communication device.
    Type: Grant
    Filed: June 14, 2005
    Date of Patent: January 1, 2008
    Assignee: Motorola, Inc.
    Inventor: Ariel L. Galan
  • Patent number: 7313372
    Abstract: A second single-ended receiver having a first stage for receiving an input signal and outputting a pair of corresponding output signals, and a second stage for receiving the pair of output signals and outputting a corresponding single output signal. First and second pull-down transistors are coupled to first and second inputs to the first stage. A bias circuit electrically biases the first stage, second stage, and first and second pull-down transistors, and a power supply provides power to those components.
    Type: Grant
    Filed: July 29, 2004
    Date of Patent: December 25, 2007
    Assignee: Avago Technologies General IP Pte Ltd
    Inventors: Manuel Salcido, Gilbert Yoh, Guy Humphrey, Salvador Salcido
  • Patent number: 7310394
    Abstract: Methods of recovering data in a received signal sent in a communications media are disclosed. Composite channel impulse responses are first estimated. Channel-tap locations are then assigned to suppress the interference noises by sequential search schemes or heuristic search schemes based on estimated composite channel impulse responses. A sequential search scheme optimizes a predetermined design criterion in a sequential manner. Also described are recursive evaluations of the design criterion and the inverses of the noise covariance matrices based on the composite channel impulse response during a sequential search. A heuristic search scheme selects channel-tap locations based on a set of pre-selected channel-tap locations. The set of pre-selected channel-tap locations is determined according to the estimated composite channel impulse response. A method of estimating energy levels of known interference sources is also described.
    Type: Grant
    Filed: January 9, 2004
    Date of Patent: December 18, 2007
    Inventor: Xiao-An Wang
  • Patent number: 7310503
    Abstract: The circuit size of a diversity receiver for an orthogonal frequency division multiplexing signal is reduced, and the diversity effect is increased, by providing a power ratio comparator that calculates a difference value as a ratio of powers derived from channel estimation results for subcarrier components received from two antennas (11), (21) and compares the calculated difference value with a predetermined threshold, and a selective/equal gain combining selector (33) that outputs one of the received demodulated signals when the comparison result indicates that the calculated difference value is greater than the threshold value.
    Type: Grant
    Filed: October 27, 2003
    Date of Patent: December 18, 2007
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Jun Ido
  • Patent number: 7299017
    Abstract: A multi-user receiver which uses at least two antenna elements and in which the influence of interference is reduced, the receiver comprises: means (200) for pre-filtering a wideband antenna signal, the pre-filtering means being determined on the basis of a spatial covariance matrix estimate, which spatial covariance matrix estimate is obtained from wideband antenna signals by sampling, arranging sampled values into a signal vector and by multiplying the signal vector by its conjugate transpose vector, means (210, 218) for removing the whitening from signals of predetermined users by using an inverse matrix of the matrix used in the whitening filter, means (202, 204, 206, 208, 210) for performing multi-path combining and multi-antenna combining.
    Type: Grant
    Filed: January 21, 2004
    Date of Patent: November 20, 2007
    Assignee: Nokia Corporation
    Inventors: Kari Pajukoski, Esa Tiirola, Juha Ylitalo
  • Patent number: 7299012
    Abstract: An electrical circuit to add and subtract differential input signals may be implemented using distributed differential transmission lines having a length substantially equal to one quarter of a wavelength of the differential input signals according to an effective electrical permeability of the transmission line. Alternatively, the electrical circuit may be implemented with lumped reactive elements.
    Type: Grant
    Filed: December 15, 2003
    Date of Patent: November 20, 2007
    Assignee: Intel Corporation
    Inventor: Meir Gordon
  • Patent number: 7289777
    Abstract: There is disclosed a method and apparatus for control of a power control loop. The method comprises the steps of: amplifying a non-constant envelope modulation signal to thereby produce an output signal; combining a power level control signal with a signal representing the envelop of modulation; comparing the combined signal to a signal representing the power level of the output signal to thereby produce a comparison signal; and attenuating the amplified signal in dependence on said comparison signal.
    Type: Grant
    Filed: June 19, 2002
    Date of Patent: October 30, 2007
    Assignee: Nokia Corporation
    Inventors: Sarachi Mohsen, Tim Land
  • Patent number: 7289834
    Abstract: Antenna techniques particularly for orthogonal frequency division multiplexed (OFDM) communications systems. A signal processing system determines weights for an adaptive antenna, the antenna including plural antenna elements each receiving a signal including plural subcarriers. The system includes plural inputs for receiving signals from the antenna elements, a time-to-frequency domain transformer for each input for transforming the signal from each input to a plurality of subcarrier signals, a first weight determiner coupled to the inputs, before the time-to-frequency domain transformer in the signal path, and configured to determine a first set of weights, one for each input, and a second weight determiner coupled to the first weight determiner and configured to determine, from the determination of the first set of weights, at least one second set of weights including a frequency-domain weight for a subcarrier signal derived from each of the inputs.
    Type: Grant
    Filed: March 11, 2003
    Date of Patent: October 30, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yong Sun, Hidehiro Matsuoka
  • Patent number: 7280810
    Abstract: Multimode, multi-function, multiple modulator-demodulator (modem) system containing a fingerprint sensor, detection, identification, authentication, and processing device for one or multiple fingerprint information to activate one or multiple modulators for signal transmission and generation of authentication information signals. A location information receiver and a processor device for processing and combining the location information and fingerprint information activated signals with one or more additional user generated signals. Processed, combined signals are provided for filtering and/or spread spectrum encoding and/or cross-correlating and connection to one or more modulators and transmitters.
    Type: Grant
    Filed: August 3, 2005
    Date of Patent: October 9, 2007
    Inventor: Kamilo Feher
  • Patent number: 7277679
    Abstract: Methods and apparatuses, including computer program products, for spatial processing in a remote terminal unit. One embodiment is a wireless remote terminal receiver in a wireless terminal unit for operation in a wireless communication system. The wireless remote terminal receiver includes an antenna array, and a receive processing unit to process signals received by the antenna array by applying a selected spatial processing mode of a plurality of spatial processing modes. The modes include one or more modes of one or more spatial processing methods. The receiver also includes a selector to select the spatial processing mode from the plurality of spatial processing modes. The selecting includes selecting the spatial processing method in the case that the set of spatial processing modes are of more than one spatial processing method.
    Type: Grant
    Filed: October 7, 2002
    Date of Patent: October 2, 2007
    Assignee: Arraycomm, LLC
    Inventors: Craig H. Barratt, Athanasios A. Kasapi
  • Patent number: 7260370
    Abstract: The present invention provides a method and system for operating a wireless communication system in which received signals from a plurality of antennas are weighted and combined with a beam forming operation to form an output signal. The beam forming operation determines weights adjusted to increase a desired signal power in the output signal while reducing the power in the output signal of out-of-band components. In an embodiment of the present invention, beam forming operations are performed with maximal ratio combining (MRC). Alternatively, a constant modulus algorithm (CMA) can be used for beam forming operations. In an alternate embodiment, improved interference suppression is performed with a novel algorithm referred to as an interference nulling algorithm (INA). The INA receives an error signal which is 180° out of phase with a combination of the channels for individual antennas, referred to as the SUM channel.
    Type: Grant
    Filed: December 10, 2003
    Date of Patent: August 21, 2007
    Inventors: James June-Ming Wang, Jack Winters, Meng Chang Doong, Chau Chin Yang