Noise Or Interference Elimination Patents (Class 455/114.2)
  • Patent number: 9596541
    Abstract: A method and system for improving echo suppression and/or duplexity of handsfree telephone applications is presented. An echo suppression unit for an electronic device comprising a loudspeaker and a microphone is described. The microphone is configured to capture a transmit signal, wherein the transmit signal comprises an echo of a receive signal rendered by the loudspeaker. The echo suppression unit is configured to determine, based on the receive signal, whether the receive signal comprises a first frequency component causing the echo of the receive signal to comprise a distortion component. The distortion component comprises one or more frequencies which are not comprised within the first frequency component. Furthermore, the echo suppression unit is configured to apply a post-filter to the transmit signal, if it is determined that the receive signal comprises the first frequency component. The post-filter is configured to selectively attenuate the distortion component.
    Type: Grant
    Filed: September 8, 2014
    Date of Patent: March 14, 2017
    Assignee: Dialog Semiconductor B.V.
    Inventors: Michiel Helsloot, Georgios Flamis, Gavin Radolan
  • Patent number: 9543991
    Abstract: Compression of an input signal prior to high power radio frequency (RF) amplification and transmission is disclosed. A compression device can receive an input signal and generate a compressed signal that can be passed to an amplification stage to reduce intermodulation effects. The compression device can further generate compression information that can be transmitted to enable a mobile device receiving an amplified version of the compressed signal and the compression information to decompress the amplified version of the compressed signal. Further, a mobile device that can receive an amplified compressed signal and compression information, such that the mobile device can decompress the amplified compressed signal, is also disclosed. The disclosed subject matter can enable use of lower cost, smaller, and less complex RF amplifiers within a wireless network environment.
    Type: Grant
    Filed: July 22, 2015
    Date of Patent: January 10, 2017
    Assignee: AT&T MOBILITY II LLC
    Inventor: Sheldon Kent Meredith
  • Patent number: 9526109
    Abstract: Systems, methods, and software described herein provide enhancements for monitoring communication data for multiple applications on a wireless device. In particular, a wireless access node is configured to monitor signal to noise data for a first frequency band from a second frequency band. When the signal to noise data meets noise criteria, the access point schedules observation periods in the first frequency band to determine intermodulation distortion for the first frequency band from the second frequency band. Based on the intermodulation distortion meeting distortion criteria, the access point schedules the second frequency band to transmit data only when the first frequency band is neither transmitting nor receiving data.
    Type: Grant
    Filed: October 1, 2015
    Date of Patent: December 20, 2016
    Assignee: Sprint Communications Company L.P.
    Inventors: Andrew Mark Wurtenberger, Sreekar Marupaduga, Patrick J. Schmidt
  • Patent number: 9510094
    Abstract: A mobile device uses externals microphone signals to improve the estimate of background noise that it computes. In order to improve voice quality in a first signal that is produced by an internal microphone, the mobile device identifies an external microphone device within proximity of the mobile device. The mobile device establishes a wireless connection with the external microphone device. The mobile device receives a second signal from the external microphone device through the wireless connection. The second signal is produced by a microphone of the external microphone device. The mobile device generates a noise profile based on the second signal, and then suppresses background/ambient noise from the first signal based on the noise profile. Other embodiments are also described.
    Type: Grant
    Filed: April 9, 2014
    Date of Patent: November 29, 2016
    Assignee: Apple Inc.
    Inventors: Baptiste P. Paquier, Bryan J. James, Aram M. Lindahl
  • Patent number: 9489608
    Abstract: An RFID card includes a smartcard controller that receives power from a host device. The RFID card also includes a small inductive device capable of inductive coupling with an RFID reader. The small inductive device is small enough to fit in the form factor of a memory card or SIM card. Enhancement circuits enhance the usable read and write distance of the RFID card.
    Type: Grant
    Filed: October 17, 2014
    Date of Patent: November 8, 2016
    Assignee: Tyfone, Inc.
    Inventors: Siva G. Narendra, Saurav Chakraborty, Prabhakar Tadepalli
  • Patent number: 9483722
    Abstract: An RFID card includes a smartcard controller that receives power from a host device. The RFID card also includes a small inductive device capable of inductive coupling with an RFID reader. The small inductive device is small enough to fit in the form factor of a memory card or SIM card. Enhancement circuits enhance the usable read and write distance of the RFID card.
    Type: Grant
    Filed: October 17, 2014
    Date of Patent: November 1, 2016
    Assignee: Tyfone, Inc.
    Inventors: Siva G. Narendra, Saurav Chakraborty, Prabhakar Tadepalli
  • Patent number: 9474033
    Abstract: Adjustment of a downlink transmit power parameter, such as a ceiling level, is disclosed. Signal-to-noise type information and committed power information can be employed to determine the ceiling level adjustment. A ceiling level can be a predetermined cap on transmission power for downlink channels between a user equipment and a base station. Where there is sufficient headroom in total transmission power and a power level greater than the predetermined ceiling can be effective, the ceiling can be adjusted to greater values than the predetermined value. Where total transmission power is more committed, ceiling adjustment can be prevented. Further, where there is no adequate benefit from increasing the ceiling, the adjustment of the ceiling can be prevented. While some instances can result in optimized transmission levels below the ceiling, instances can also be accommodated where the ceiling is to be increased.
    Type: Grant
    Filed: November 5, 2015
    Date of Patent: October 18, 2016
    Assignee: AT&T MOBILITY II LLC
    Inventors: Vladimir Gusavac, Manish Vaishnav
  • Patent number: 9461756
    Abstract: A method and apparatus for calibrating a terminal is provided. The apparatus includes a modem; a transmission chain configured to process a signal input from the modem and transmit the processed signal via an antenna; a reception chain configured to process a signal received via the antenna and transmit the processed signal to the modem; and a connector configured to connect an output of the transmission chain and an output of the reception chain via an envelope detector and a switch configured to turn on/off the envelope detector, calibrate a DC offset voltage and I and Q signals of the transmission chain by inputting a one-tone signal of 1 MHz into the transmission channel via the modem in a state where the envelope detector is turned on, and calibrate a second order input intercept point (IIP2) characteristic value by adjusting the signal input into the modem via the reception channel.
    Type: Grant
    Filed: March 5, 2015
    Date of Patent: October 4, 2016
    Assignee: Samsung Electronics Co., Ltd
    Inventor: Young-Taek Lee
  • Patent number: 9391590
    Abstract: A filter and method for filtering a signal are disclosed. The filter is equivalent to a plurality of bi-quad filters connected in series, and is implemented on a digital processor that receives a sequence of signal values at a sampling rate characterized by a sampling interval and generates a filtered signal value upon receiving each received signal value. The filter has a latency that is less than the sampling interval. The filtered values can be generated by adding a term to a received signal value and multiplying the sum by a gain constant that depends on the filter constants. The added term does not depend on the current received signal value. The filter can be implemented in fixed-point integer arithmetic.
    Type: Grant
    Filed: August 27, 2013
    Date of Patent: July 12, 2016
    Assignee: Keysight Technologies, Inc.
    Inventors: Daniel Y. Abramovitch, Christopher R. Moon
  • Patent number: 9385794
    Abstract: To provide a mobile terminal apparatus, radio base station apparatus and radio communication method that enable accurate precoding weights to be generated in coordinated multipoint transmission, a radio communication method of the invention is characterized in that a mobile terminal apparatus (10) performs channel estimation using a downlink reference signal, selects a PMI using the obtained channel estimation value, measures an IQI using at least the channel estimation value and the PMI, and transmits at least the PMI and IQI to a radio base station apparatus, and that the radio base station apparatus generates precoding weights using the PMI and IQI, and performs coordinated multipoint transmission utilizing MIMO transmission using the precoding weights.
    Type: Grant
    Filed: February 21, 2012
    Date of Patent: July 5, 2016
    Assignee: NTT DOCOMO, INC.
    Inventors: Anass Benjebbour, Satoshi Nagata
  • Patent number: 9369094
    Abstract: An exemplary system comprises a linearizer module, a first upconverter module, a power amplifier module, a signal sampler module, and a downconverter module. The linearizer module may be configured to receive a first intermediate frequency signal and to adjust the first intermediate frequency signal based on a reference signal and a signal based on a second intermediate frequency signal. The first upconverter module may be configured to receive and up-convert a signal based on the adjusted first intermediate frequency signal to a radio frequency signal. The power amplifier module may be configured to receive and amplify a power of a signal based on the radio frequency signal. The signal sampler module may be configured to sample a signal based on the amplified radio frequency signal. The downconverter module may be configured to receive and down-convert a signal based on the sampled radio frequency signal to the second intermediate frequency signal.
    Type: Grant
    Filed: October 20, 2011
    Date of Patent: June 14, 2016
    Assignee: Aviat U.S., Inc.
    Inventors: Frank Matsumoto, Youming Qin, David C. M. Pham
  • Patent number: 9319788
    Abstract: A sound processing apparatus (400) is provided with: a directivity synthesis processing unit (410) for generating a first directivity sound pick-up signal by synthesizing a first sound pick-up signal and a relatively delayed second sound pick-up signal and a second directivity sound pick-up signal by synthesizing a relatively delayed first sound pick-up signal and a second sound pick-up signal; a comparison signal calculation unit (440) for generating a non-directivity level signal indicating the level of a sum of the directivity sound pick-up signals and a directivity level signal by adding the levels of the directivity sound pick-up signals; a level comparison unit (451) for acquiring the difference between the levels of the non-directivity level signal and the directivity level signal; and a delay control unit (452) for adjusting the delay amount such that the difference between the levels becomes smaller.
    Type: Grant
    Filed: October 24, 2012
    Date of Patent: April 19, 2016
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Yutaka Banba, Takeo Kanamori
  • Patent number: 9300264
    Abstract: A receiver includes LNA-mixer arrangement, a current buffer arrangement and an analog filter arrangement. The LNA-mixer arrangement receives a plurality of input signals and provides a wide-band input match for a specified frequency range of operation. The LNA-mixer arrangement includes a plurality of LNA structures and a plurality of mixer structures where each of the LNA structure path is coupled to a single mixer structure. The LNA-mixer arrangement outputs a first signal. The current buffer arrangement receives the first signal and reduces the Image Rejection (IR) asymmetry between the high frequency portion and the low frequency portion of the first signal as well as provides a gain to the first signal. The current buffer arrangement outputs a second signal. The analog filter arrangement receives the second signals and perform filtering and calibration.
    Type: Grant
    Filed: August 22, 2014
    Date of Patent: March 29, 2016
    Assignee: MEDIATEK INC.
    Inventors: Ravikanth Suravarapu, Saravanan Rajapandian, Narayanan Baskaran, Caiyi Wang, Jing Li
  • Patent number: 9287904
    Abstract: Measures for interference reduction for an envelope branch type transmitter. Such measures may include determination of a target frequency span for reducing interference caused by an envelope branch type transmitter, and configuration of a differential delay between a signal branch and an envelope branch of the envelope branch type transmitter on the basis of the determined target frequency span.
    Type: Grant
    Filed: October 8, 2013
    Date of Patent: March 15, 2016
    Assignee: BROADCOM CORPORATION
    Inventor: Markus Nentwig
  • Patent number: 9258819
    Abstract: A femtocell includes a frequency offset detecting module and a frequency correction module. The frequency offset detecting module calculates frequency offset and detects whether the frequency offset exceeds a default frequency offset. The frequency detecting offset module counts the time of the frequency offset exceeding the default frequency offset, and detects whether the counted number of times exceed a first default number. The frequency detecting module re-calculates frequency offset after an internal when the counted number of times does not exceed the first default number. The frequency correction module uses a last calculated frequency offsets to adjust the frequency of the femtocell, when the counted number of times exceed the first default number. A method of adjusting frequency of the femtocell is also provided.
    Type: Grant
    Filed: April 23, 2014
    Date of Patent: February 9, 2016
    Assignee: HON HAI PRECISION INDUSTRY CO., LTD.
    Inventor: Yu-Hung Lin
  • Patent number: 9203529
    Abstract: Aspects of the present disclosure relate to determining the location and/or density of vias that form part of an RF isolation structure of a packaged module and the resulting RF isolation structures. From electromagnetic interference (EMI) data, locations of where via density can be increased and/or decreased without significantly degrading the EMI performance of the RF isolation structure can be identified. In certain embodiments, one or more vias can be added and/or removed from a selected area of the packaged module based on the EMI data.
    Type: Grant
    Filed: December 19, 2014
    Date of Patent: December 1, 2015
    Assignee: Skyworks Solutions, Inc.
    Inventors: Howard E. Chen, Matthew Sean Read, Hoang Mong Nguyen, Anthony James LoBianco, Guohao Zhang, Dinhphuoc Vu Hoang
  • Patent number: 9202748
    Abstract: A radio frequency (RF) module comprises an electrical reference, or ground, plane to which one or more RF devices disposed on the module are electrically coupled, and may be disposed beneath the RF devices. The reference plane may be segmented as to form one or more segments of the reference plane that are at least partially electrically isolated from surrounding segments or devices. A module may have a plurality of devices disposed thereon, wherein separate, at least partially isolated reference planes, correspond to different devices of the module. The reference plane may be etched or cut to achieve such segmentation.
    Type: Grant
    Filed: September 27, 2013
    Date of Patent: December 1, 2015
    Assignee: Skyworks Solutions, Inc.
    Inventors: Anthony James LoBianco, Hoang Mong Nguyen
  • Patent number: 9202747
    Abstract: A radio frequency (RF) module comprises a conductive top layer configured to improve RF interference-shielding functionality with respect to one or more RF devices disposed on the module. The conductive top layer may be segmented as to form one or more segments of the top layer that are at least partially electrically isolated from surrounding segments or devices. A module may have a plurality of devices disposed thereon, wherein separate, at least partially isolated, top conductive layers correspond to different devices of the module. The top layer may be etched or cut to achieve such segmentation.
    Type: Grant
    Filed: September 27, 2013
    Date of Patent: December 1, 2015
    Assignee: Skyworks Solutions, Inc.
    Inventors: Howard E. Chen, Matthew Sean Read, Anthony James LoBianco, Hoang Mong Nguyen, Guohao Zhang, Dinhphuoc Vu Hoang
  • Patent number: 9197257
    Abstract: Disclosed herein is a passive, voltage mode transmitter assembly and method of operation. The passive, voltage mode transmitter assembly comprises a baseband filter configured to filter a source baseband signal, a harmonics filter, connected to the baseband filter, configured to remove harmonics from the filtered, source baseband signal, a passive, voltage mode mixer, connected to the harmonics filter, configured to up-convert an output of the harmonics filter to a radio signal, and a power amplifier, connected to the passive, voltage mode mixer, configured to amplify the radio signal.
    Type: Grant
    Filed: March 18, 2014
    Date of Patent: November 24, 2015
    Assignee: ST-ERICSSON SA
    Inventor: Andreas Axholt
  • Patent number: 9190962
    Abstract: A radio frequency (RF) power amplifier (PA) is reconfigured to operate in a low power mode from a high power mode. The RF PA has a first RF amplifier is connected to the first and second inputs of a first transformation network. The RF PA has a second a second RF amplifier connected to a second transformation network. During high power mode, both RF amplifiers drive a load coupled to the transformation networks. In low power mode the first RF amplifier is disabled and the first and second inputs of the first transformation are coupled together so as to change the load impedance seen by the second RF amplifier. The second RF amplifier continues to supply power to the load during operation in the low power mode.
    Type: Grant
    Filed: July 7, 2014
    Date of Patent: November 17, 2015
    Assignee: QUALCOMM INCORPORATED
    Inventors: Susanne A. Paul, Marius Goldenberg
  • Patent number: 9154080
    Abstract: A mixer with calibration circuit includes a first gm stage unit, a second gm stage unit, a first detecting unit, a second detecting unit, a comparison block, a control unit and a compensator. The first detecting unit and the second detecting unit are respectively connected to different gm stage unit, and the comparison block compares voltage signals of the first detecting unit and the second detecting unit. The control unit adjusts a current signal of the comparison block according to the comparative result of voltage signals of the first detecting unit and the second detecting unit. Further, the compensator adjusts the first gm stage unit and the second gm stage unit according to the current signal. Thereafter, the improvement of the LO leakage of the mixer can be achieved.
    Type: Grant
    Filed: September 12, 2013
    Date of Patent: October 6, 2015
    Assignee: Airoha Technology Corp.
    Inventor: Chao Hsi Chuang
  • Patent number: 9136989
    Abstract: In an embodiment, an apparatus comprises an in-phase-quadrature (IQ) signal amplifier having an IQ baseband input, an IQ mixer input connected to the IQ signal amplifier, a carrier leakage detector connected to outputs of the IQ mixer, and a carrier-null offset signal generator connected to the carrier leakage detector. The IQ mixer is configured to be driven by an IQ carrier signal. The carrier leakage detector is configured to output an in-phase leakage level measurement and a quadrature leakage level measurement in the absence of an IQ baseband signal at the IQ baseband input. The carrier-null offset signal generator is configured to (i) inject an in-phase carrier-null offset signal based on the in-phase leakage level measurement and (ii) inject a quadrature carrier-null offset signal based on the quadrature leakage level measurement.
    Type: Grant
    Filed: October 10, 2013
    Date of Patent: September 15, 2015
    Assignee: Motorola Solutions, Inc.
    Inventors: Dennis M. Drees, Bryan A. Hoon
  • Patent number: 9113427
    Abstract: This disclosure provides systems, methods, and apparatus for mobile transmit diversity. In one aspect a method of controlling a transmit power level of a wireless communications apparatus is provided. The method includes adjusting the transmit power level of a transmitter of the wireless communications apparatus to a first transmit power level in response to detecting a de-sense event indicative of interference with a signal received by a receiver of the wireless communications apparatus due to emissions from the transmitter. The method further includes maintaining the transmit power level substantially at the first transmit power level for a first time interval in response to adjusting the transmit power level to the first transmit power level. The method further includes adjusting a transmit power level limit of the transmitter after the time interval at a rate for a second time interval.
    Type: Grant
    Filed: December 7, 2012
    Date of Patent: August 18, 2015
    Assignee: QUALCOMM Incorporated
    Inventors: Rashid Ahmed Akbar Attar, Troy Russell Curtiss, Ammar Taiyebi Kitabi, Chintan Shirish Shah, Athreya Prasad, Sunil Rajendran, Ramchandran Srinivasan
  • Patent number: 9065506
    Abstract: A low pass filter connected between an individual port of a switch device and a high-frequency switch module attenuates the second harmonic and the third harmonic of a transmission signal input to a first transmission signal input terminal. Further, the inductances/capacitances of inductors and capacitors defining the low pass filter are set such that the phase of a harmonic signal generated by a power amplifier is different by 180° from the phase of a harmonic signal produced as a result of the low pass filter shifting the phase of a harmonic signal generated due to distortion in a switch device, in an end portion on the first transmission signal input terminal side.
    Type: Grant
    Filed: July 26, 2013
    Date of Patent: June 23, 2015
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Takanori Uejima
  • Patent number: 9042838
    Abstract: A system and methods for cancelling transmission leakage signals in a wide bandwidth Distributed Antenna System (“DAS”) having remote units is disclosed. An internal cancellation circuit within the remote unit is employed to reduce the transmitted leakage signals by generating a cancellation signal. This cancellation signal is added to the received signal to cancel the transmission leakage signal in the receiving signal path. A pilot signal generation circuit is employed to optimize the cancellation circuit operating parameters. The frequency of the pilot signal is swept over a range to determine the pilot frequency having the highest electromagnetic coupling. The amplitude and phase of the cancellation signal is then optimized to minimize the level of transmission leakage in the receiving transmission path.
    Type: Grant
    Filed: August 22, 2011
    Date of Patent: May 26, 2015
    Assignee: Intel Corporation
    Inventor: Richard Neil Braithwaite
  • Patent number: 9042847
    Abstract: Embodiments of the present invention provide a filter, a receiver, a transmitter, and a transceiver. The filter includes a resonant cavity component, a microstrip filtering component, and two connecting pieces, where the resonant cavity component includes at least two resonant cavities connected in parallel, each resonant cavity is provided with a resonator and a tuning screw, the microstrip filtering component includes a dielectric substrate and a microstrip positioned on the dielectric substrate, one of the connecting pieces matches and connects one end of the microstrip to the resonator on one resonant cavity, the other connecting piece matches and connects the other end of the microstrip to the resonator on another resonant cavity, and impedance of the resonant cavity component is less than impedance of the microstrip filtering component.
    Type: Grant
    Filed: September 24, 2013
    Date of Patent: May 26, 2015
    Assignee: Hauwei Technologies Co., Ltd.
    Inventor: Yanzhao Zhou
  • Patent number: 9037089
    Abstract: A method and apparatus relate to coexistence of multiple RF subsystems on a communication device. An apparatus may include a plurality of radio frequency (RF) subsystems configured to receive or transmit communication signals; and an interference table indicative of zones of interference among the multiple RF subsystems, the zones of interference being based on RF measurements. At least one of the RF subsystems comprises a coexistence module configured to communicate coexistence-related messages with of the other RF subsystems, the coexistence-related messages being based on the zones of interference.
    Type: Grant
    Filed: November 14, 2012
    Date of Patent: May 19, 2015
    Assignee: BROADCOM CORPORATION
    Inventors: Aimin Sang, Kamesh Medapalli
  • Patent number: 9036734
    Abstract: Integrated circuits with wireless communications circuitry having digital predistortion (DPD) circuitry are provided. The digital predistortion circuitry may include a forward path filter, a time domain alignment (TDA) circuit, a frequency domain alignment (FDA) circuit, and an adaption circuit. The TDA circuit may receive power amplifier input signals and power amplifier output signals and may include a cross correlator, a peak detector, and a delay circuit for performing coarse time domain alignment (i.e., to align the power amplifier input and output signals). The FDA circuit may include a fast Fourier transform circuit, a matrix multiplier, and a matrix inverter for performing frequency domain alignment. The adaption circuit may analyze the aligned signals output from the FDA circuit to produce impulse response coefficients that are then used to control the forward path filter. The forward path filter may serve to predistort transmit signals prior to radio-frequency amplification.
    Type: Grant
    Filed: July 22, 2013
    Date of Patent: May 19, 2015
    Assignee: Altera Corporation
    Inventors: Volker Mauer, Shahin Gheitanchi, Benjamin Thomas Cop
  • Patent number: 9037101
    Abstract: A remote radio head system (RRH) transmits first Radio-Frequency-signals (signals) at a first frequency-band (band) and second signals at a second band. The RRH receives and processes first control-data (data) to determine a first duty-cycle (cycle). In response to the first data and based on the first cycle, the RRH switches power between a first power amplifier system (PA) and a second PA and transmits the first signals at the first band through the first PA and transmits the second signals at the second band through the second PA. The RRH receives and processes second data to determine a second cycle. Responding to the second data and based on the second cycle, the RRH switches power between the first PA and the second PA and transmits the first signals at the first band through the first PA and transmits the second signals at the second band through the second PA.
    Type: Grant
    Filed: December 27, 2013
    Date of Patent: May 19, 2015
    Assignee: Sprint Communications Company L.P.
    Inventors: Sharath Somashekar, Cody Carl Heinrich, Mark Alan Wade, Xianghong Zeng
  • Patent number: 9031521
    Abstract: A power amplifier system includes an input operable to receive an original value that reflects information to be communicated and an address data former operable to generate a digital lookup table key. The power amplifier system also includes a predistortion lookup table coupled to the address data former and a power amplifier having an output and coupled to the predistortion lookup table. The power amplifier system further includes a feedback loop providing a signal associated with the output of the power amplifier to the predistortion lookup table and a switch disposed in the feedback loop and operable to disconnect the predistortion lookup table from the output of the power amplifier.
    Type: Grant
    Filed: April 4, 2014
    Date of Patent: May 12, 2015
    Assignee: Dali Systems Co. Ltd.
    Inventors: Dali Yang, Jia Yang
  • Patent number: 9031527
    Abstract: Apparatus, systems, and methods implementing techniques for calibrating a filter circuit. A comparator generates an output based on a filter output amplitude signal and a reference amplitude signal. A calibration logic unit receives the comparator output and produces a component code that is used by the filter circuit to adjust one or more component values.
    Type: Grant
    Filed: June 30, 2010
    Date of Patent: May 12, 2015
    Assignee: Marvell International Ltd.
    Inventors: King Chun Tsai, Sang Wong Son, Wayne A. Loeb
  • Patent number: 9025686
    Abstract: The present invention relates to clipping thresholds adjustment for Crest Factor Reduction CFR in a radio unit, wherein the radio unit comprises one or more clipping stages that apply respective clipping thresholds to clip input signals, comprising: determining a target threshold for the clipping stages based on a target PAR and the amplitudes or powers of the input signals, estimating the direction in which original PAR of the input signals changes by comparing amplitudes of the clipped signals from the clipping stages with the target threshold, and adjusting the clipping thresholds based on the estimated direction. The present invention also relates to dynamic stage control. With the present invention, clipping thresholds and clipping stages are adaptively changes with dynamic original PAR of input signals and the efficiency of power amplifier is increased with a low implementation cost.
    Type: Grant
    Filed: February 17, 2011
    Date of Patent: May 5, 2015
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventor: Tao Gu
  • Patent number: 9026162
    Abstract: Apparatus configured to be implemented in a first wireless communication device, having corresponding non-transitory computer-readable media, comprise a memory configured to store a coexistence schedule, wherein the coexistence schedule defines WLAN intervals and non-WLAN intervals; a WLAN transceiver configured to transmit WLAN signals in an IBSS network; a non-WLAN transceiver configured to transmit wireless non-WLAN signals; and a coexistence circuit configured to allow the WLAN transceiver to transmit the WLAN signals in the IBSS network only during the WLAN intervals, wherein the coexistence circuit is further configured to allow the non-WLAN transceiver to transmit the wireless non-WLAN signals only during the non-WLAN intervals; and wherein the coexistence circuit is further configured to cause the WLAN transceiver to transmit one or more coexistence request messages, each indicating a duration of at least one of a respective one of the WLAN intervals, and a respective one of the non-WLAN intervals.
    Type: Grant
    Filed: April 27, 2012
    Date of Patent: May 5, 2015
    Assignee: Marvell World Trade Ltd.
    Inventors: Sarang Shrikrishna Wagholikar, Harish Ramamurthy, Rajesh Shreeram Bhagwat, Matthew L. Semersky
  • Publication number: 20150118980
    Abstract: Certain aspects of the present disclosure provide methods and apparatus for calibrating a transceiver for wireless communications. One example method generally includes configuring a first oscillating signal as an input signal to at least a portion of a receiver (RX) path, calibrating a residual sideband (RSB) of the receiver path using a second oscillating signal as a local oscillating signal for the receiver path, and calibrating an RSB of a transmitter (TX) path by routing an output of the transmitter path to the receiver path, after calibrating the RSB of the receiver path. Another example method generally includes routing an output of a transmitter path to a receiver path, using a first local oscillating signal for the transmitter path, using a second local oscillating signal for the receiver path, and measuring an output of the receiver path as a local oscillator (LO) leakage for the transmitter path.
    Type: Application
    Filed: April 29, 2014
    Publication date: April 30, 2015
    Applicant: QUALCOMM INCORPORATED
    Inventors: Lai Kan LEUNG, Chiewcharn NARATHONG, Jianyun HU
  • Patent number: 9020066
    Abstract: Single-bit transmitter modulator having a digital pulse shaping filter configured to shape data pulses of an inphase signal and quadrature signal; an upsampling filter configured to increase the sample rate of the inphase signal and quadrature signal; a sigma-delta modulator providing a one-bit inphase output signal and a one-bit quadrature output signal; an inphase low-order analog low pass filter coupling the one-bit inphase output signal to an inphase channel input of a quadrature modulator, and a quadrature low-order analog low pass filter coupling the one-bit quadrature output signal to a quadrature channel input of a quadrature modulator; and, wherein the quadrature modulator is connected to a carrier signal generator and is configured to generate an inphase and quadrature modulated carrier.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: April 28, 2015
    Assignee: Innophase Inc.
    Inventors: Yang Xu, Xuejun Zhang
  • Patent number: 9020067
    Abstract: Distortion and aliasing reduction for digital to analog conversion. Synthesis of one or more distortion terms made based on a digital signal (e.g., one or more digital codewords) is performed in accordance with digital to analog conversion. The one or more distortion terms may correspond to aliased higher-order harmonics, distortion, nonlinearities, clipping, etc. Such distortion terms may be known a priori, such as based upon particular characteristics of a given device, operational history, etc. Alternatively, such distortion terms may be determined based upon operation of a device and/or based upon an analog signal generated from the analog to conversion process. For example, frequency selective measurements made based on an analog signal generated from the digital to analog conversion may be used for determination of and/or adaptation of the one or more distortion terms. One or more DACs may be employed within various architectures operative to perform digital to analog conversion.
    Type: Grant
    Filed: April 1, 2013
    Date of Patent: April 28, 2015
    Assignee: Broadcom Corporation
    Inventors: Thomas J. Kolze, Bruce J. Currivan, Ramon A. Gomez
  • Publication number: 20150111510
    Abstract: A method and apparatus for cancelling, from signals received by a radio device in a first frequency band, interference generated by the radio device in the first frequency band when the radio device transmits simultaneously radio signals on at least a second frequency band.
    Type: Application
    Filed: October 22, 2013
    Publication date: April 23, 2015
    Applicant: Broadcom Corporation
    Inventors: Pierre BAUDIN, Mikael GUENAIS
  • Patent number: 9014298
    Abstract: Transmission quality is improved in an environment in which direct waves dominate in a transmission method for transmitting a plurality of modulated signals from a plurality of antennas at the same time. All data symbols used in data transmission of a modulated signal are precoded by hopping between precoding matrices so that the precoding matrix used to precode each data symbol and the precoding matrices used to precode data symbols that are adjacent to the data symbol in the frequency domain and the time domain all differ. A modulated signal with such data symbols arranged therein is transmitted.
    Type: Grant
    Filed: August 27, 2014
    Date of Patent: April 21, 2015
    Assignee: Panasonic Intellectual Property Corporation of America
    Inventors: Yutaka Murakami, Tomohiro Kimura, Mikihiro Ouchi
  • Patent number: 9014637
    Abstract: Examples are disclosed for switching frequency control of an on-chip or integrated voltage regulator. In some examples, a switch frequency of an integrated voltage regulator may be monitored. A determination of whether the monitored switch frequency causes radio signal interference may cause the switch frequency to be adjusted to eliminate or reduce the radio signal interference. Other examples are described and claimed.
    Type: Grant
    Filed: September 27, 2013
    Date of Patent: April 21, 2015
    Assignee: Intel Corporation
    Inventors: Harry G. Skinner, Dawson W. Kesling, Jeremy Shrall
  • Patent number: 9008694
    Abstract: An apparatus and method is provided for indoor/outdoor transition detection of devices to improve selection of the navigation algorithms. A mobile device can scan resources such as radio frequency (RF) sources in its vicinity and compare the scanned resources with a set of indoor-only resources to determine whether the mobile device is located inside a structure (e.g., indoor) or outside the structure (e.g., outdoor). The techniques provide an apparatus and method to determine when a device transitions between indoor and outdoor to efficiently use appropriate algorithm for positioning and/or navigation.
    Type: Grant
    Filed: June 29, 2012
    Date of Patent: April 14, 2015
    Assignee: Broadcom Corporation
    Inventors: Richard Fuller, Steven Malkos
  • Patent number: 9007131
    Abstract: A frequency-control circuit includes a phase frequency detector configured to receive a reference frequency signal and generate an output detection signal. The phase frequency detector can be configured to detect a difference in phase and frequency between the reference frequency signal and a feedback of the output frequency signal. The frequency-control circuit also includes a frequency divider that is configured to apply a correction voltage to a feedback of the output frequency signal, the correction voltage being a function of a pulling signal having one or more unwanted frequency components. The frequency-control circuit also includes a loop filter configured to filter the output detection signal including the correction voltage and generate a control voltage signal. The frequency-control circuit also includes a voltage-controlled oscillator configured to receive the control voltage signal and generate an output frequency signal.
    Type: Grant
    Filed: March 13, 2013
    Date of Patent: April 14, 2015
    Assignee: Broadcom Corporation
    Inventors: Ahmad Mirzaei, Hooman Darabi
  • Patent number: 9002301
    Abstract: Embodiments of the present disclosure provide system and method for generating a transmission signal. A transmitter generates and transmits a transmission signal based on signal components. Circuitry that is coupled to the transmitter receives complex plane components of a signal to be transmitted and alters the signal such that a complex plane trajectory of the signal passes nearer to an origin of a complex plane of the complex plane trajectory than does an original complex plane trajectory of the signal. The circuitry determines the signal components to be transmitted by the transmitter based on the altered signal.
    Type: Grant
    Filed: December 3, 2012
    Date of Patent: April 7, 2015
    Assignee: Marvell International Ltd.
    Inventors: Luca Vercesi, Fernando De Bernardinis
  • Patent number: 9001680
    Abstract: A method, apparatus and computer program product provide improved detection of overlapping wireless networks. In this regard, the method, apparatus and computer program product may utilize a processor, such as a processor on a wireless access point, to determine one or more parameters for a scan of a wireless network to identify overlapping networks. Wireless stations may utilize the parameters to determine the content of a scan report generated from a scan of the wireless network. The wireless stations may further utilize the parameters to determine which values should be monitored and/or recorded during the scan of the network. The wireless stations may respond to the access point with results corresponding to the parameters requested by the access point, and the access point may use the results to determine channel access parameters for other devices on the network, such as the wireless stations.
    Type: Grant
    Filed: July 16, 2012
    Date of Patent: April 7, 2015
    Assignee: Broadcom Corporation
    Inventors: Timo K. Koskela, Anna Pantelidou, Samuli Turtinen, Sami-Jukka Hakola
  • Patent number: 8995565
    Abstract: This invention includes a waveform analyzing means (13) for calculating an estimated value of a back-off value required by a power amplifier (2), which amplifies a high-frequency signal generated from a baseband signal (I, Q) to a predetermined transmission power, by analyzing the waveform of the baseband signal (I, Q), and a control means (14) for controlling at least one of the amplitude of high-frequency power input to the power amplifier (2) and the supply power of the power amplifier (2) on the basis of the estimated value. The invention calculates the estimated value of a back-off value by analyzing the waveform of a baseband in this manner, and hence need not generate a table in advance by calculating a back-off value for each combination of code channels. The invention can therefore be applied to even a case in which the number of code channels greatly increases, and can effectively prevent an increase in adjacent channel leakage power due to a signal obtained by multiplexing these code channels.
    Type: Grant
    Filed: May 17, 2007
    Date of Patent: March 31, 2015
    Assignee: Lenovo Innovations Limited (Hong Kong)
    Inventor: Masaki Ichihara
  • Patent number: 8989253
    Abstract: A technique for a reconditioning equalizer filter for non-constant envelope signals is described. The input to a transmitter chain is modified by a reconditioning equalizer filter, prior to being applied to the transmitter. The reconditioning equalizer filter modifies and smoothens the amplitude of the signal. The modified and smoothened signal has its peaks reduced which results in lower Crest Factor. The input to the reconditioning equalizer filter could be a baseband, intermediate frequency (IF) or radio frequency (RF) signal. When the signal is an IF or RF signal, it needs to be down-converted to baseband before being applied to the reconditioning equalizer filter. The reconditioning equalizer filter could be performed in a digital or analog domain.
    Type: Grant
    Filed: June 17, 2014
    Date of Patent: March 24, 2015
    Assignee: Altera Corporation
    Inventor: Kiomars Anvari
  • Patent number: 8989755
    Abstract: A method for communication in a wireless telecommunication network is provided. The method comprises transmitting, by a first cell, to a first UE, a first signal on a resource block configured to be shared by more than one cell; and transmitting, by a second cell, to a second UE, a second signal on the same resource block, wherein a specification of a location of the resource block is included in configuration information available to the first cell and the second cell.
    Type: Grant
    Filed: February 26, 2013
    Date of Patent: March 24, 2015
    Assignee: BlackBerry Limited
    Inventors: Siva Dharshan Muruganathan, Yongkang Jia, Yi Song, Hua Xu, Vahid Pourahmadi, Robert Mark Harrison, Shiwei Gao
  • Patent number: 8989680
    Abstract: According to one aspect, a method is provided for determining a state of a receiver on a transmission line. The method may comprise, for example, evaluating a first voltage arising at a circuit point between an impedance and a transmission line coupled to the impedance, wherein the impedance is coupled between a transmitter and the receiver, and determining a state of the receiver based on the first voltage. According to further aspects, various apparatuses are provided for performing this and other methods.
    Type: Grant
    Filed: January 22, 2008
    Date of Patent: March 24, 2015
    Assignee: Infineon Technologies AG
    Inventor: Andreas Hebenstreit
  • Patent number: 8989305
    Abstract: Disclosed herein are a method and apparatus for generating multiband Radio Frequency (RF) signals in maritime wireless communication. The apparatus includes a baseband conversion unit, a phase compensation unit, a Direct Current (DC) offset compensation unit, and an RF transmission unit. The baseband conversion unit converts RF signals corresponding to a baseband modulation signal having a negative frequency and a baseband modulation signal having a positive frequency into baseband signals, respectively. The phase compensation unit eliminates the images of multiband signals so as to correspond to the baseband signals. The DC offset compensation unit compensates the baseband modulation signals for DC offsets using the multiband signals from which the images have been eliminated. The RF transmission unit generates the RF signals using the signals which have been compensated for the DC offsets, and sends the RF signals via an antenna.
    Type: Grant
    Filed: February 25, 2013
    Date of Patent: March 24, 2015
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Jin-Kyu Choi, Jong-Min Park, Dae-Seung Yoo, Gwang-Ja Jin, Byung-Tae Jang, Dong-Sun Lim
  • Patent number: 8983407
    Abstract: Radio frequency (RF) power amplifier (PA) circuitry, which transmits RF signals is disclosed. The RF PA circuitry includes a final stage, a final stage current digital-to-analog converter (IDAC), and a final stage temperature compensation circuit. A final stage current reference circuit may provide an uncompensated final stage reference current to the final stage temperature compensation circuit, which receives and temperature compensates the uncompensated final stage reference current to provide a final stage reference current. The final stage IDAC uses the final stage reference current in a digital-to-analog conversion to provide a final stage bias signal to bias the final stage. The temperature compensation provided by the final stage temperature compensation circuit is selectable.
    Type: Grant
    Filed: November 3, 2011
    Date of Patent: March 17, 2015
    Assignee: RF Micro Devices, Inc.
    Inventors: William David Southcombe, David E. Jones, Hui Liu, Chris Levesque, Scott Yoder, Terry J. Stockert
  • Patent number: 8977226
    Abstract: A mobile terminal including a transceiver having a plurality of output terminals; a plurality of power amplifier units respectively connected to the plurality of output terminals, and configured to amplify a first or second signal output by the output terminals and to output the amplified first or second signal to a plurality of antennas respectively connected the plurality of power amplifiers; and a receiving module configured to receive a third signal through a receiving antenna disposed to be spaced apart from the plurality of antennas and to output the received third signal to the transceiver. Further, the receiving module includes first and second filters configured to control an intermodulation distortion (IMD) signal included in the third signal due to the output of the first or second signal.
    Type: Grant
    Filed: January 2, 2013
    Date of Patent: March 10, 2015
    Assignee: LG Electronics Inc.
    Inventor: Hoonyong Kim