Amplitude Modulation Patents (Class 455/108)
  • Patent number: 10271354
    Abstract: A device and/or method for dynamically adjusting a CCA threshold in an addressable unit that is suitable for communication in a wireless network, the method performed in the addressable unit and comprising autonomously increasing the CCA threshold with successful data transmissions and/or autonomously decreasing the CCA threshold with unsuccessful data transmissions.
    Type: Grant
    Filed: March 31, 2015
    Date of Patent: April 23, 2019
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Siva Kupanna Subramani, Fengming Cao, Parag Gopal Kulkarni, Mahesh Sooriyabandara
  • Patent number: 10193521
    Abstract: An impedance matching network includes a first terminal, a second terminal, and a reference potential terminal. The impedance matching network further includes a first shunt branch between the first terminal and the reference potential terminal, the first shunt branch including a capacitive element. The impedance matching network also includes a second shunt branch between the second terminal and the reference potential terminal, the second shunt branch including an inductive element. Furthermore, the impedance matching network includes a transmission line transformer with a first inductor path and a second inductor path, wherein the first inductor path connects the first terminal and the second terminal. An alternative impedance matching network includes a transformer and an adaptive matching network. The transformer is configured to transform an impedance connected to a first port so that a corresponding transformed impedance lies within a confined impedance region in a complex impedance plane.
    Type: Grant
    Filed: October 5, 2015
    Date of Patent: January 29, 2019
    Assignee: Infineon Technologies AG
    Inventor: Winfried Bakalski
  • Patent number: 10028297
    Abstract: Techniques for improving data rates at mobile terminals that are subject to periodic channel interruptions in a beyond-line-of-sight communication system are disclosed, including improved encoding and decoding systems that identify blockages and modify receiver operation during blockages to reduce data errors. In certain embodiments, encoding, symbol mapping, interleaving, and use of unique periodic identifiers function to enable a series of packets that may be received in a blockage impaired channel with reduced errors.
    Type: Grant
    Filed: October 13, 2016
    Date of Patent: July 17, 2018
    Assignee: ViaSat, Inc.
    Inventors: Donald Wilcoxson, John O'Neill, Daniel Chester, Brian Sleight, Changping Li
  • Patent number: 9927469
    Abstract: A power detector constituted of: a transconductance element arranged to output a rectified detection current, the magnitude thereof arranged to increase exponentially responsive to a linear increase in the amplitude of an input signal; and at least one p-n junction based device, a function of the rectified detection current arranged to flow there through. The output of the power detector is a function of the voltage across the at least one p-n junction based device.
    Type: Grant
    Filed: December 21, 2015
    Date of Patent: March 27, 2018
    Assignee: Microsemi Corporation
    Inventor: Brian Eplett
  • Patent number: 9893682
    Abstract: A linearization circuit that reduces intermodulation distortion in an amplifier output receives a first signal that includes a first frequency and a second frequency and generates a difference signal having a frequency approximately equal to the difference of the first frequency and the second frequency. The linearization circuit generates an envelope signal based at least in part on a power level of the first signal and adjusts a magnitude of the difference signal based on the envelope signal. When the amplifier receives the first signal at an input terminal and the adjusted signal at a second terminal, intermodulation between the adjusted signal and the first signal cancels at least a portion of the intermodulation products that result from the intermodulation of the first frequency and the second frequency.
    Type: Grant
    Filed: June 24, 2016
    Date of Patent: February 13, 2018
    Assignee: Skyworks Solutions, Inc.
    Inventors: Yu Zhu, Boshi Jin, Steven Christopher Sprinkle, Florinel G. Balteanu, Oleksiy Klimashov, Dylan Charles Bartle, Paul T. DiCarlo
  • Patent number: 9813029
    Abstract: A linearization circuit reduces intermodulation distortion in a differential amplifier that includes a first stage and a second stage. The linearization circuit receives a first signal that includes a first frequency and a second frequency and generates a difference signal having a frequency approximately equal to the difference of the first frequency and the second frequency, generates an envelope signal based at least in part on a power level of the first signal, and adjusts a magnitude of the difference signal based on the envelope signal. When the differential amplifier receives the first signal at an input terminal, the first stage receives the adjusted signal, and the second stage does not receive the adjusted signal, intermodulation between the adjusted signal and the first signal cancels at least a portion of the intermodulation between the first frequency and the second frequency from the output of the differential amplifier.
    Type: Grant
    Filed: June 24, 2016
    Date of Patent: November 7, 2017
    Assignee: Skyworks Solutions, Inc.
    Inventors: Yu Zhu, Dylan Charles Bartle, Oleksiy Klimashov, Paul T. DiCarlo
  • Patent number: 9768811
    Abstract: Embodiments of the present invention disclose a pre-distortion system, including a pre-distortion circuit, a transmission circuit, a power amplifier, a feedback circuit, and a learning circuit. The pre-distortion circuit acquires an in-band intermodulation distortion model coefficient vector, a cross-band modulation distortion model coefficient vector, and an out-of-band intermodulation distortion model coefficient vector that are learned by the learning circuit according to an output signal of the power amplifier, and performs pre-distortion processing on an input digital intermediate frequency signal. Correspondingly, the embodiments of the present invention further disclose a pre-distortion method, which can eliminate impact caused by out-of-band intermodulation distortion on the power amplifier.
    Type: Grant
    Filed: October 28, 2016
    Date of Patent: September 19, 2017
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Tingjian Tian, Yanqing Zhao, Yunfu Dou
  • Patent number: 9456271
    Abstract: An audio signal outputting apparatus and method for adjusting an output gain of an audio signal are provided. The audio signal outputting apparatus includes: a pulse width modulation (PWM) unit which generates a carrier signal, compares a signal level of the carrier signal with a signal level of an audio signal, and generates a PWM signal based on a result of the comparison; a controller which, based to a level of the audio signal, controls the PWM unit to change a signal shape of the carrier signal to adjust a duration of a logic high level of the PWM signal; and a switching power unit which amplifies the PWM signal generated by the PWM unit and outputs the amplified PWM signal.
    Type: Grant
    Filed: December 9, 2011
    Date of Patent: September 27, 2016
    Assignee: SAMSUNG ELECTRONICS CO., LTD.
    Inventor: Dong-hyun Lim
  • Patent number: 9337734
    Abstract: Embodiments provide a DC-DC converter (DC-DC=direct current to direct current) for envelope tracking. The DC-DC converter includes a digital control stage and a driving stage. The digital control stage is configured to provide a digital control signal based on digital information describing an amplitude of a digital baseband transmit signal. The driving stage is configured to provide a supply voltage for an RF amplifier (RF=radio frequency) based on the digital control signal.
    Type: Grant
    Filed: September 3, 2014
    Date of Patent: May 10, 2016
    Assignee: Intel Deutschland GmbH
    Inventor: Franz Kuttner
  • Patent number: 9295001
    Abstract: A signal amplification apparatus includes a first modulator configured to receive an envelope signal, use a predetermined reference level to separate the received envelope signal into a first period and a second period, digitally modulate a signal of the second period to output the digitally modulated signal to a first output terminal, and output a signal of the first period to a second output terminal. Further, the signal amplification apparatus includes a second modulator configured to mix the digital modulated signal input through the first output terminal with a phase modulated carrier signal; an envelope modulator configured to output the signal of the first period as a power supply signal; and a power amplifier configured to amplify the mixed signal output by the second modulator to output the amplified signal.
    Type: Grant
    Filed: January 8, 2014
    Date of Patent: March 22, 2016
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Seunghyun Jang, Sung Jun Lee, Young Kyun Cho, Bong Hyuk Park, Jae Ho Jung, Kwangchun Lee
  • Patent number: 9231624
    Abstract: A method of calibrating a polar amplification stage including a main signal path and a magnitude signal path, the method comprising: generating signals (108, 142) for the main signal path and the magnitude signal path for operating an amplifier (102) between a linear mode of operation and a saturated mode of operation; detecting (114) first and second peaks in a signal at the output of the amplifier (102) representing transitions between the linear and saturated modes of operation; and adjusting (124) the timing in one of the main signal path and the amplitude signal path in dependence on a relative difference between the size of the detected first and second peaks.
    Type: Grant
    Filed: May 28, 2012
    Date of Patent: January 5, 2016
    Assignee: SNAPTRACK, INC.
    Inventor: Nicholas Shute
  • Patent number: 9203416
    Abstract: Various configurations and arrangements of systems and methods for compensating for variations in VCO output frequencies are described. A system in accordance with the disclosure can include an oscillator circuit including an oscillator, a first variable capacitance diode coupled to the oscillator and a second variable capacitance diode coupled to the oscillator. The system further includes a voltage source configured to apply a first voltage to the oscillator circuit to cause the output signal to comprise a selected frequency, the selected frequency being based on a received reference voltage. The system further includes a controller circuit configured to compare an operating voltage of the oscillator to the reference voltage while the first voltage is applied to the oscillator; and apply a second voltage to the oscillator circuit based on the comparison. The second voltage compensates for a difference between the reference voltage and the first voltage.
    Type: Grant
    Filed: June 10, 2013
    Date of Patent: December 1, 2015
    Assignee: Broadcom Corporation
    Inventors: Dmitriy Rozenblit, Rahul Magoon
  • Patent number: 9148182
    Abstract: Systems and methods are provided for implementing and using multiband transceiver architectures. In a transmit subsystem that comprises a plurality of transmit paths, a frequency spectrum that is used for transmission of signals may be segmented into a plurality of segments, and each of the segments may be allocated to one of the plurality of transmit paths. Further, performance in each of the plurality of transmit paths may be monitored during transmission of signals, and operation of the transmit subsystem and each of the plurality of transmit paths may be controlled based on the monitored performance. Such control may comprise dynamically performing one or more of modifying operation of one or more of the plurality of transmit paths, modifying assignment of plurality of segments to the plurality of transmit paths, and modifying segmentation of the frequency spectrum.
    Type: Grant
    Filed: October 9, 2014
    Date of Patent: September 29, 2015
    Assignee: MAXLINEAR, INC.
    Inventors: Curtis Ling, Leonard Dauphinee, Rahul Bhatia
  • Patent number: 9065507
    Abstract: A mixing stage includes a first modulation stage that receives an input signal from a first common node of the mixing stage, a first local oscillator input that receives a local oscillator signal, and a first modulation signal output adapted to provide a first modulated signal. A second modulation stage of the mixing stage includes a second input that receives a phase inverted representation of the input signal from a second common node of the mixing stage, a second local oscillator input that receives the local oscillator signal, and a second modulation signal output adapted to provide a second modulated signal. A current generation circuit provides a supply current to the first common node and to the second common node. A current control circuit is adapted to superimpose an offset current to the current of at least one node of the first common node and the second common node.
    Type: Grant
    Filed: September 5, 2013
    Date of Patent: June 23, 2015
    Assignee: Infineon Technologies AG
    Inventors: Saverio Trotta, Herbert Knapp
  • Patent number: 9030240
    Abstract: A signal processing device enables a high quality enhanced signal to be obtained, and includes: a transform unit which transforms a mixed signal in which a first signal and a second signal are mixed, into a phase component and an amplitude component or a power component in each frequency; a first control unit which rotates the phase component in a predetermined frequency; a second control unit which compensates the amplitude component or the power component in the predetermined frequency according to the amount of change of the amplitude component or the power component rotated by the first control unit; and a synthesizing unit which synthesizes the phase component rotated by the first control unit, and the amplitude component or the power component compensated by the second control unit.
    Type: Grant
    Filed: November 21, 2011
    Date of Patent: May 12, 2015
    Assignee: NEC Corporation
    Inventor: Ryoji Miyahara
  • Patent number: 9020027
    Abstract: An integrated circuit includes: a digitally-controlled power generation stage for converting an input signal to a radio frequency (RF) carrier, the digitally-controlled power generation stage including a plurality of selectable switching devices capable of adjusting an envelope of the RF carrier; and a pulse width modulator (PWM) generator arranged to generate a PWM control signal according to a fractional word and operably coupleable to the plurality of selectable switching devices of the digitally-controlled power generation stage; wherein the PWM generator inputs the PWM control signal to a subset of the plurality of the selectable switching devices such that a PWM signal adjusts the envelope of the RF carrier output from the digitally-controlled power generation stage.
    Type: Grant
    Filed: January 24, 2014
    Date of Patent: April 28, 2015
    Assignee: MediaTek Singapore Pte. Ltd.
    Inventors: Robert Bogdan Staszewski, Min Park
  • Patent number: 9008229
    Abstract: A device for obtaining a RCC signal and related methods are described herein improves the reliability of the RCC signal reception and demodulation. In one aspect, a device configured to obtain a RCC signal includes: a receiving circuit to receive an analog AM RCC signal and to process said analog AM RCC signal to generate a digital AM RCC signal; and a demodulation circuit in connection with said receiving circuit, to demodulate said digital AM RCC signal to generate the RCC signal. In another aspect, a method for obtaining a RCC signal includes: processing a received analog AM RCC signal to generate a digital AM RCC signal; and demodulating said digital AM RCC signal to generate said RCC signal. Since the digital processing method is more reliable than the analog processing method, the reliability of RCC signal reception and demodulation are improved.
    Type: Grant
    Filed: September 30, 2011
    Date of Patent: April 14, 2015
    Assignee: Beijing KT Micro, Ltd.
    Inventor: Zhen Li
  • Patent number: 8995935
    Abstract: Disclosed herein is a wireless communication device, including: a plurality of communication units for transmission adapted to modulate and transmit a transmission subject signal; the communication units for transmission including a communication unit or units for transmission which adopt a method which modulates the amplitude and a communication unit or units for transmission which adopt a modulation method which modulates at least the phase or the frequency and requires transmission power lower than that of the method which modulates the amplitude.
    Type: Grant
    Filed: August 26, 2010
    Date of Patent: March 31, 2015
    Assignee: Sony Corporation
    Inventor: Norihito Mihota
  • Patent number: 8989244
    Abstract: A receiver is provided that receives signals from a device under test (DUT) for one or more modes of operation. For each mode, the system detects beacon transmission signals from the DUT, and counts the number of beacons for a period of time. If the count is not consistent with an expected count, e.g. a stored value, the system may preferably provide an output to indicate that there is a problem with the DUT. If the count is consistent with the expected count, the system may preferably perform further testing for other modes of operation. If the count output of the DUT is consistent with expected counts over each of the operation modes, the system may provide an indication that the DUT has passed the beacon tests.
    Type: Grant
    Filed: December 10, 2012
    Date of Patent: March 24, 2015
    Assignee: NETGEAR, Inc.
    Inventors: Joseph Amalan Arul Emmanuel, Jonathan M. Hummel, Shahrokh M. Zardoshti
  • Patent number: 8983405
    Abstract: Various embodiments provide for systems and methods for wireless communications that implement transmitter protection schemes using spatial combining. The protection scheme implemented by some embodiments provides for a number of benefits, including without limitation: hitless protection; constant power monitoring for each wireless channel being utilized; extra gain to wireless signals transmitted; beam steering, beam hopping, and beam alignment capabilities; and varying levels of transmission path protection (e.g., 1+1 protection, or 1+N protection). Additionally, the features of some embodiments may be applied to a variety of wireless communications systems including, for example, microwave wireless systems, cellular phone systems and WiFi systems.
    Type: Grant
    Filed: September 3, 2013
    Date of Patent: March 17, 2015
    Assignee: Aviat U.S., Inc.
    Inventors: Ying Shen, David Schafer
  • Patent number: 8934856
    Abstract: A system and method provide for calibrating the frequency response of an electronic filter. The system and method include a radio transmitter with both in-phase and quadrature baseband paths. Each baseband path includes a numerically controlled oscillator (“NCO”), a digital signal path, a digital-to-analog converter (“DAC”), and an analog filter. A low frequency tone is applied from the NCO from one of the baseband path, while a high frequency tone is applied from the NCO in the other baseband path. An analog peak detector at output determines which analog filter has the largest amplitude at the output. The peak detector offset between the two analog filters is offset by stimulating the in-phase and quadrature baseband paths with the respective NCOs to find an amplitude difference between the output signals from the NCOs that makes the output of the analog filters the same.
    Type: Grant
    Filed: October 12, 2012
    Date of Patent: January 13, 2015
    Assignee: Analog Devices, Inc.
    Inventors: David J. McLaurin, Christopher Mayer
  • Patent number: 8918068
    Abstract: A radio frequency (RF) power limiter including a signal conductor having an input end and an output end and first and second limiter stages. The first limiter stage comprises a plurality of stacked diode strings arranged in anti-parallel with respect to the signal conductor. The second limiter stage comprises a second plurality of stacked diode strings arranged in anti-parallel with respect to the signal conductor. An all pass filter is arranged between the first and second limiter stages.
    Type: Grant
    Filed: January 12, 2012
    Date of Patent: December 23, 2014
    Assignee: Lockheed Martin Corporation
    Inventors: David R. Helms, Dana J. Sturzebecher
  • Patent number: 8890658
    Abstract: An RFID system using an M pulse amplitude modulation (M-PAM) or M quadrature amplitude modulation (M-QAM) scheme using a plurality of load-modulators, a plurality of antennas, and a communication method thereof are provided. The RFID system includes: an RFID tag; and a reader device communicating with the RFID device, wherein the RFID tag includes: N load-modulators an N antennas communicating with the reader device in any one scheme of M-pulse amplitude modulation (M-PAM) and M-quadrature amplitude modulation (M-QAM) in which modulation of an M level is performed and operated corresponding to the M level.
    Type: Grant
    Filed: August 14, 2012
    Date of Patent: November 18, 2014
    Assignees: Electronics and Telecommunications Research Institute, Seoul National University of Technology Center for Industry Collaboration
    Inventors: Ji Hoon Bae, Chan Won Park, Hyung Chul Park, Jong Suk Chae, Cheol Sig Pyo
  • Patent number: 8868011
    Abstract: Embodiments of apparatuses, methods, and systems for a radio frequency amplification circuit providing for fast loadline modulation are generally described herein. Other embodiments may be described and claimed.
    Type: Grant
    Filed: April 30, 2012
    Date of Patent: October 21, 2014
    Assignee: TriQuint Semiconductor, Inc.
    Inventor: Peter V. Wright
  • Patent number: 8867651
    Abstract: Systems and methods for combining signals from multiple active wireless transmitters are discussed herein. An exemplary system comprises a radio enclosure, a first transmitting RFU, a second transmitting RFU, and a combiner. The first transmitting RFU may be configured to receive a signal, upconvert the signal, compare a phase of the upconverted signal to a predetermined phase value, and adjust the phase of the signal based on the comparison to provide a first phase-adjusted upconverted signal. The second transmitting RFU may be configured to receive the signal, upconvert the signal, compare a phase of the upconverted signal to the predetermined phase value, and adjust the phase of the signal based on the comparison to provide a second phase-adjusted upconverted signal. The coupler may be configured to combine the first and second phase-adjusted upconverted signals to create an output signal and provide the output signal to an antenna for transmission.
    Type: Grant
    Filed: September 29, 2011
    Date of Patent: October 21, 2014
    Assignee: Aviat U.S., Inc.
    Inventor: Ying Shen
  • Patent number: 8862050
    Abstract: A novel terrestrial wireless communications technique for terrestrial portable terminals including hand-held mobile devices and fixed wireless instruments, utilizing a spoke-and-hub communications system, having a plurality of individual hubs and/or base-stations all in communications with the portable terminals. The portable terminals and the hubs are assigned to use incompatible polarity formats in terms of circularly polarity (CP) and linearly polarity (LP). In forward links, a signal processed by the LP ground telecommunications hubs is radiated through multiple antennas with various LP polarities to an individual CP user simultaneously. The multiple paths are organized via assignments of a plurality of polarities, frequency slots, and directions by wavefront multiplexing/demultiplexing techniques such that the same communications assets including frequency spectrum may be re-used by other users. The same polarity diversity methods can be extended to peer-to-peer communications.
    Type: Grant
    Filed: September 13, 2011
    Date of Patent: October 14, 2014
    Assignee: Spatial Digital Systems, Inc.
    Inventor: Donald C. D. Chang
  • Patent number: 8855559
    Abstract: Exemplary embodiments are directed to forward link signaling. A method may include modulating an input bias signal of a power amplifier according to data to be transmitted on a wireless power transmit signal. The method may further include modulating an amplitude of the wireless power transmit signal generated by the power amplifier in response to the modulated input bias signal.
    Type: Grant
    Filed: October 11, 2013
    Date of Patent: October 7, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: William Henry Von Novak, III, Stanley Slavko Toncich, Cheng F. Tan, Kevin Douglas Lee, Linda Stacey Irish
  • Patent number: 8848813
    Abstract: A peak-to-average ratio (PAR) of a signal is reduced by clipping the signal at a threshold level and replacing desired frequency tones of the clipped signal with set of frequency tones of the signal. In one embodiment, the PAR of a signal is reduced by adding a peak cancellation signal to the received signal. The peak cancellation signal is generated by clipping the received signal at a threshold level and generating a difference signal by subtracting the received signal from the clipped signal. The peak cancellation signal thus generated is scaled by a scaling factor and added to the received signal to reduce the PAR of the received signal. The scaling factor is adjusted to maintain the desired quality of the received signal. In one embodiment, the PAR of an orthogonal frequency division multiplexed (OFDM) signal may be reduced.
    Type: Grant
    Filed: December 10, 2012
    Date of Patent: September 30, 2014
    Assignee: Texas Instruments Incorporated
    Inventors: Sarma S Gunturi, Atul Deshpande
  • Patent number: 8843180
    Abstract: Embodiments for at methods, apparatus and systems for operating a voltage regulator are disclosed. One apparatus includes a switching voltage regulator, wherein the switching voltage regulator includes a series switch element, a shunt switch element, a switching controller and a switched output filter. The switching controller is configured to generate a switching voltage through controlled closing and opening of the series switch element and the shunt switch element. The switched output filter filters the switching voltage and generates a regulated output voltage, wherein the switched output filter includes a plurality of capacitors that are selectively included within the switched output filter.
    Type: Grant
    Filed: June 5, 2013
    Date of Patent: September 23, 2014
    Assignee: R2 Semiconductor, Inc.
    Inventors: James E. C. Brown, Daniel Dobkin, Pablo Moreno Galbis, Cory Severson, Lawrence M. Burns
  • Patent number: 8831512
    Abstract: An apparatus and method is disclosed to negotiate communications parameters between near field communications (NFC) capable devices. In some embodiments, the NFC capable devices operate in a negotiation phase to negotiate one or more communications parameters prior to transferring information. In other embodiments, the NFC capable devices simultaneously negotiate the one or more communications parameters with the transferring of the information.
    Type: Grant
    Filed: June 28, 2011
    Date of Patent: September 9, 2014
    Assignee: Broadcom Corporation
    Inventors: Peter Laws, John Waters
  • Patent number: 8787497
    Abstract: The present invention relates to a method of transmitting and a method of receiving signals and corresponding apparatus. One aspect of the present invention relates to an efficient L1 signaling method for an efficient transmitter and an efficient receiver using the efficient L1 signaling method for an efficient cable broadcasting.
    Type: Grant
    Filed: July 23, 2009
    Date of Patent: July 22, 2014
    Assignee: LG Electronics Inc.
    Inventors: Woo Suk Ko, Sang Chul Moon
  • Patent number: 8781414
    Abstract: An envelope detector includes an input receiving a digital input signal indicative of a magnitude of a signal to be amplified by a power amplifier. A circuit is provided for generating an analog envelope signal based on the digital input signal. The envelope detector includes an output for outputting the analog envelope signal.
    Type: Grant
    Filed: December 11, 2012
    Date of Patent: July 15, 2014
    Assignee: Intel Mobile Communications GmbH
    Inventors: Krzysztof Dufrene, Harald Pretl, Patrick Ossmann
  • Patent number: 8774317
    Abstract: A system and method for a radio controlled clock receiver adapted to extract timing and time information from a phase modulated signal. The official time signal is broadcast from a central location using a modified modulation scheme, which adds phase modulation over the legacy amplitude modulation, such as the legacy WWVB pulse width modulated (PWM)/amplitude shift keying (ASK) modulation, thereby allowing for improved performance. The information modulated onto the phase contains a known synchronization sequence having good autocorrelation properties, error-correcting coding for the time information and notifications of daylight-saving-time (DST) transitions that are provided months in advance. The modulation scheme is based on a form of phase modulation, such as binary-phase-shift-keying (BPSK) or phase reversal keying (PRK).
    Type: Grant
    Filed: March 16, 2012
    Date of Patent: July 8, 2014
    Assignee: Everset Technologies, Inc.
    Inventor: Oren E. Eliezer
  • Patent number: 8737936
    Abstract: An amplitude modulation circuit in a polar transmitter includes a digital-to-analog converter (DAC), a filter, a gm stage, and a calibration module. The DAC is arranged to be coupled to an amplitude modulation signal input in a normal mode. The filter is coupled to the DAC, and the gm stage is coupled to the filter. The calibration module has an input coupled to the gm stage, and an output coupled to a node on a path between the DAC and the gm stage. A method for calibrating an amplitude offset in the polar transmitter includes: generating an amplitude offset calibration signal according to an amplitude modulation signal generated from the gm stage; and transmitting the amplitude offset calibration signal via the output of the calibration module to a node on a path between the DAC and the gm stage so as to calibrate the amplitude offset.
    Type: Grant
    Filed: October 23, 2011
    Date of Patent: May 27, 2014
    Assignee: Mediatek Inc.
    Inventors: Hsin-Hung Chen, Hsiang-Hui Chang, Chun-Pang Wu, Yung-Yu Lin, Jong-Woei Chen
  • Patent number: 8737925
    Abstract: A method for remotely and dynamically controlling adjacent satellite interference comprising monitoring one or more off-axis signals emitted by one or more remote transmitters; determining whether one or more of the off-axis signals is creating adjacent satellite interference (ASI), off axis emissions and inband interference that is higher than a predetermined level of acceptable interference, and transmitting a control signal to at least one of the one or more remote transmitters in response to the determination that the one or more off-axis signals is creating interference that is higher than the predetermined level of acceptable interference, the control signal initiating an adjustment to one or more transmission parameters of the one or more remote transmitters such that interference resulting from the one or more off-axis signals emitted by the one or more remote transmitters is reduced or eliminated.
    Type: Grant
    Filed: June 16, 2011
    Date of Patent: May 27, 2014
    Assignee: Comtech EF Data Corp.
    Inventors: Michael Beeler, Jeffery Harig, Wallace Davis, Frederick Morris, Cris Mamaril
  • Patent number: 8731502
    Abstract: An integrated circuit comprises frequency generation circuitry for controlling a frequency source for use in an automotive radar system. The frequency generation circuitry comprises low-path modulation circuitry arranged to generate a first, low-path control signal for providing lower frequency modulation of the frequency source, the low-path modulation circuitry comprising a Phase Locked Loop (PLL) arranged to generate the low-path control signal for controlling the frequency source and a fractional-N divider located within a feedback loop of the PLL, and frequency pattern control module operably coupled to the fractional-N divider and arranged to control the fractional-N divider, by way of at least a first, lower frequency pattern control signal. The frequency generation circuitry further comprises high-path modulation circuitry arranged to generate a second, high-path control signal for providing higher frequency modulation of the frequency source.
    Type: Grant
    Filed: February 10, 2010
    Date of Patent: May 20, 2014
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Didier Salle, Olivier Doare, Stephane Dugalleix
  • Patent number: 8725218
    Abstract: Embodiments for at methods, apparatus and systems for operating a voltage regulator are disclosed. One method includes generating, by a switching controller, a switching voltage through controlled closing and opening of a series switch element and a shunt switch element. Further, the method includes generating, by a switchable output filter, a regulated output voltage by filtering the switching voltage, wherein the switchable output filter comprises a plurality of capacitors that are selectively included within the switchable output filter.
    Type: Grant
    Filed: February 18, 2012
    Date of Patent: May 13, 2014
    Assignee: R2 Semiconductor, Inc.
    Inventors: James E. C. Brown, Daniel Dobkin, Pablo Moreno Galbis, Cory Severson, Lawrence M. Burns
  • Patent number: 8725214
    Abstract: A Method of Tuning a Frequency Agile Electrically Small Tactical AM Broadcast Band Antenna System (NC#102174) comprising determining a desired operating frequency for a frequency agile electrically small tactical AM broadcast band antenna system; configuring tophat jumpers of the frequency agile electrically small tactical AM broadcast band antenna system to operate near the desired operating frequency; erecting an antenna of the frequency agile electrically small tactical AM broadcast band antenna system; transmitting a signal through the frequency agile electrically small tactical AM broadcast band antenna system; adjusting inductor values of an antenna tuning unit of the frequency agile electrically small tactical AM broadcast band antenna system so that the frequency agile electrically small tactical AM broadcast band antenna system operates at the desired operating frequency.
    Type: Grant
    Filed: November 30, 2012
    Date of Patent: May 13, 2014
    Assignee: The United States of America, as Represented by the Secretary of the Navy
    Inventor: Ken Allen Crawley
  • Patent number: 8718577
    Abstract: According to techniques described herein LO leakage may be automatically minimized in a transmitter chain, even though the leakage may be varying in nature. In an embodiment a target signal for transmission is received. An offset for reducing the effects of the LO leakage is applied to the target signal. After the offset is applied, the target signal is converted to a transmission signal using the LO. A power associated with the transmission signal is determined. The offset is then adjusted based on the power associated with the transmission signal. In another embodiment, the offset signal is adjusted in a manner that minimizes the power associated with the transmission signal.
    Type: Grant
    Filed: November 29, 2012
    Date of Patent: May 6, 2014
    Assignee: Exalt Communications Incorporated
    Inventor: Peter Smidth
  • Patent number: 8706063
    Abstract: A power amplifier (PA) envelope power supply, which provides an envelope power supply signal to radio frequency (RF) PA circuitry, and a process to prevent undershoot of the PA envelope power supply is disclosed. The process includes determining if an envelope control signal to the PA envelope power supply has a step change from a high magnitude to a low magnitude that exceeds a step change limit. Such a step change may cause undershoot of the PA envelope power supply. As such, if the step change exceeds the step change limit, the envelope control signal is modified to use an intermediate magnitude for period of time. Otherwise, if the step change does not exceed the step change limit, the envelope control signal is not modified.
    Type: Grant
    Filed: November 28, 2011
    Date of Patent: April 22, 2014
    Assignee: RF Micro Devices, Inc.
    Inventors: Hirofumi Honjo, Brian Baxter, Stuart Williams, Roman Zbigniew Arkiszewski, David E. Jones, Chris Levesque, William David Southcombe, Scott Yoder, Terry J. Stockert
  • Publication number: 20140106681
    Abstract: A wireless device includes: an antenna; and a polar-modulation transmitter coupled to the antenna and configured for two-point modulation, the transmitter including: a data input; a first signal path including a multiplier coupled to the data input and a voltage-controlled oscillator gain adaptation module coupled to the multiplier and configured to provide a gain value to the multiplier; and a second signal path coupled to the data input and including an analog phase-locked loop (PLL) including a voltage-controlled oscillator (VCO) coupled to the first signal path.
    Type: Application
    Filed: October 12, 2012
    Publication date: April 17, 2014
    Applicant: Qualcomm Incorporated
    Inventors: Lai Kan Leung, Yiwu Tang, Chiewcharn Narathong
  • Patent number: 8682267
    Abstract: A wireless transmission apparatus that can accurately select an optimal modulation scheme on a per block basis in a multi-carrier communication system in which block division of subcarriers and adaptive modulation are performed. In this wireless transmission apparatus, a propagation path characteristics acquisition section acquires the average SNR and SNR variance for each block, which are estimated by a wireless reception apparatus, using received signals inputted from a reception RF section and outputs these to an assignment section. The assignment section selects a modulation scheme for each block based on the average SNR and SNR variance of each block inputted from the propagation path characteristics acquisition section and modulation sections modulate multi-carrier signals included in each block, with the modulation scheme for each block selected by the assignment section.
    Type: Grant
    Filed: February 10, 2012
    Date of Patent: March 25, 2014
    Assignee: Harris Corporation
    Inventors: Jun Cheng, Kenichi Miyoshi
  • Patent number: 8674812
    Abstract: In a communication system including a RFID tag, which has a function to record information and a function to carry out wireless communication with an external device and is capable of transmission with using both FM modulation and AM modulation, and a reader/writer for writing and reading information onto and from the RFID tag via wireless communication, a transmission to transmit information from the RFID tag to the reader/writer is carried out with using one of the FM modulation and the AM modulation at the RFID tag. If the reader/writer fails to decode a signal transmitted with using the one of the FM modulation and the AM modulation, transmission with respect to the information is carried out with using the other of the FM modulation and the AM modulation at the RFID tag. In this manner, reading error of data sent from the RFID tag is prevented.
    Type: Grant
    Filed: August 29, 2011
    Date of Patent: March 18, 2014
    Assignee: Riso Kagaku Corporation
    Inventor: Takahiro Fushimi
  • Patent number: 8675725
    Abstract: An integrated circuit comprises a digitally-controlled power generation stage (DPA) for converting an input signal to a radio frequency (RF) carrier, the DPA comprising a plurality of selectable switching devices capable of adjusting an envelope of the RF carrier; and a pulse width modulator (PWM) generator arranged to generate a PWM control signal and operably coupleable to the plurality of selectable switching devices of the DPA. The PWM generator inputs the PWM control signal to a subset of the plurality of the selectable switching devices such that a PWM signal adjusts the envelope RF carrier output from the DPA.
    Type: Grant
    Filed: January 31, 2011
    Date of Patent: March 18, 2014
    Assignee: MediaTek Singapore Pte. Ltd.
    Inventors: Robert Bogdan Staszewski, Min Park
  • Patent number: 8665781
    Abstract: A user equipment, for use in a wireless communication system, includes a unit operable to measure a received signal quality in a receiver, a unit operable to report the measuring received signal quality to the transmitter, or a unit operable to report a selected modulation and coding scheme to the transmitter.
    Type: Grant
    Filed: April 6, 2007
    Date of Patent: March 4, 2014
    Assignee: Fujitsu Limited
    Inventors: Yassin Aden Awad, Michiharu Nakamura
  • Patent number: 8660209
    Abstract: A transmitter is provided. The transmitter includes a phase/frequency deviation input, a controller and a frequency modulating path. The phase/frequency deviation input receives multiple phase/frequency deviation samples. The controller outputs a modified phase/frequency deviation signal and generates a phase/frequency deviation carry-out signal in response to the phase/frequency deviation samples and a previous time sample of the phase/frequency deviation carry-out signal. The frequency modulating path performs frequency modulation in response to the modified phase/frequency deviation signal and outputs a frequency modulated carrier signal.
    Type: Grant
    Filed: September 13, 2012
    Date of Patent: February 25, 2014
    Assignee: Mediatek Inc.
    Inventors: Kai-Peng Kao, Chi-Hsueh Wang, Robert Bogdan Staszewski, Ping-Ying Wang
  • Patent number: 8655292
    Abstract: A signal separating unit separates an input signal into a first branch signal and a second branch signal in such a manner that, as the amplitude of the input signal decreases, the amplitude of the first branch signal and the second branch signal decreases and the difference between a phase of the first branch signal and a phase of the second branch signal increases and, as the amplitude of the input signal increases, the amplitude of the first branch signal and the second branch signal increases and the difference between the phase of the first branch signal and the phase of the second branch signal decreases. An amplifier amplifies the first branch signal. Another amplifier amplifies the second branch signal. A combining unit combines signals that are output from the amplifiers together, thereby generating an output signal.
    Type: Grant
    Filed: December 16, 2011
    Date of Patent: February 18, 2014
    Assignee: Fujitsu Limited
    Inventor: Toshio Kawasaki
  • Patent number: 8655289
    Abstract: A distortion compensation device includes a distortion compensator that predistorts an input signal based on delay signals and distortion compensation coefficients corresponding to the respective delay signals obtained by applying different amounts of delay to the input signal, a calculator that calculates an error signal based on the predistorted input signal and an output signal from an amplifier that amplifies the predistorted input signal, a calculator that calculates prospective distortion compensation coefficients for updating the distortion compensation coefficients, based on the error signal, a saturation processor that performs saturation processing for bringing, when the prospective distortion compensation coefficients do not fall into a preset range, the prospective distortion compensation coefficients into the preset range, and a controller that controls the updating of the distortion compensation coefficients based on pieces of coefficient saturation information indicating whether the saturation
    Type: Grant
    Filed: February 7, 2012
    Date of Patent: February 18, 2014
    Assignee: Fujitsu Limited
    Inventors: Nobukazu Fudaba, Hiroyoshi Ishikawa, Yuichi Utsunomiya, Kazuo Nagatani
  • Patent number: 8653902
    Abstract: Provided is a transmission circuit that operates highly efficiently by avoiding deterioration of the linearity of an output signal and suppressing occurrence of distortion of the output signal, when using the envelope tracking method. In this transmission circuit, offset control section (160) sets voltage that makes the corrected envelope signal level equal to or higher than the delayed envelope signal level, as offset voltage. By this means, the corrected envelope signal level becomes equal to or higher than the delayed envelope signal level, so that it is possible to prevent the power supply voltage from being lower than the optimal power supply voltage, making it possible to prevent the linearity of an output signal from deteriorating in power amplifier (130).
    Type: Grant
    Filed: May 12, 2011
    Date of Patent: February 18, 2014
    Assignee: Panasonic Corporation
    Inventor: Ryo Kitamura
  • Publication number: 20140038534
    Abstract: Configurable suppression of harmonics in a radio frequency (RF) transmitter circuit having two class-D switching amplifiers that produce a differential output signal having introduced harmonics is contemplated. A selected harmonic is used to determine a time duration. A harmonic suppression circuit modifies a radio frequency polar modulated data signal that is encoded using an amplitude component and a phase component. The modification is responsive to the determined time duration. The switching power amplifiers amplify the modified polar modulated data signal to produce an amplified signal. The amplified signal includes three signal levels, a high signal level, a middle signal level and a low signal level. The timing of transitions between the high and low signal levels represents the phase component, and the transitions include the middle signal level for the time duration, thereby suppressing the selected harmonic.
    Type: Application
    Filed: August 1, 2012
    Publication date: February 6, 2014
    Inventors: Massimo Ciacci, Jos Verlinden, Remco van de Beek