Filter In At Least One Path Patents (Class 455/306)
  • Patent number: 10079615
    Abstract: A branch circuit includes a common antenna port and separates a first communication signal including a signal in a low band and a signal in a high band and a second communication signal that is a signal in a frequency band between the low band and the high band. The branch circuit includes a first-communication-signal-line-side band elimination filter and a second-communication-signal-line-side band elimination filter and SAW filter.
    Type: Grant
    Filed: January 5, 2018
    Date of Patent: September 18, 2018
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Kuniaki Yosui, Noboru Kato
  • Patent number: 9450624
    Abstract: Interference cancellation for wideband and narrowband communications systems is provided without apriori knowledge of statistical information about an interfering signal. In one embodiment a demodulator circuit can operate in an environment where a “no lock” situation would normally occur to remove the interference and acquire signals in low signal-to-noise ratio conditions and high signal-to-interference ration conditions. In other embodiments, performance is improved by introducing statistics of the interfering signal, and these statistics regarding the communications channel and interference properties (i.e., characteristics of the interfering signal) can be adaptive or “learned” in other embodiments.
    Type: Grant
    Filed: December 19, 2014
    Date of Patent: September 20, 2016
    Assignee: STMicroelectronics (Canada), Inc.
    Inventors: Jose Augusto Lima, Antonio Mascioli
  • Patent number: 9191049
    Abstract: An adaptive cancellation circuit and method are provided. The circuit includes a main path and an auxiliary path. The main path includes a first amplifier configured to output a first amplified signal to a first mixer. The main path is configured to output a first signal comprising a wanted signal component and a distortion component. The auxiliary path includes a second amplifier configured to output a second amplified signal to a second mixer. The second mixer is connected to a filter configured to remove the wanted signal component. The auxiliary path is configured to output a second signal including the distortion component.
    Type: Grant
    Filed: May 11, 2012
    Date of Patent: November 17, 2015
    Assignee: Broadcom Corporation
    Inventors: Mohyee Mikhemar, Hooman Darabi
  • Patent number: 9178548
    Abstract: A method for processing a radio signal includes: receiving an FM in-band on-channel radio signal including a plurality of digitally modulated subcarriers in upper and lower sidebands; sampling the FM in-band on-channel radio signal to produce an input signal including complex digital samples of a combination of a desired one the upper and lower sidebands and an FM interferer; removing FM interferer components from the first signal by notch filtering to produce a notch-filtered signal; weighting the notch-filtered signal to produce a weighted notch-filtered signal; using a parametric filter to filter the input signal to produce a parametric-filtered input signal; and combining the weighted notch-filtered signal and the parametric-filtered input signal to produce an output signal. A radio receiver that implements the method is also included.
    Type: Grant
    Filed: April 21, 2014
    Date of Patent: November 3, 2015
    Assignee: iBiquity Digital Corporation
    Inventors: Brian W. Kroeger, Paul J. Peyla
  • Patent number: 9042857
    Abstract: Methods, systems, and computer readable media for wideband frequency and bandwidth tunable filtering are disclosed. According to one aspect, the subject matter described herein includes a wideband frequency and bandwidth tunable filter that splits a filter input signal into first and second input signals, modifies the first input signal to produce a first output signal, modifies the second input signal to produce a second output signal having an intermediate frequency response, and combines the first and second output signals while adjusting their relative phases and/or amplitudes to produce a filter output signal with the target frequency response. Adjustment includes splitting the second input signal into third and fourth input signals, which are modified and then combined to produce the second output signal having the intermediate frequency response.
    Type: Grant
    Filed: January 18, 2013
    Date of Patent: May 26, 2015
    Assignee: PHYSICAL DEVICES, LLC
    Inventors: Frederick Vosburgh, Charley Theodore Wilson, III, Jonathan Ryan Wilkerson
  • Patent number: 9031526
    Abstract: A communication device includes a receiver that is capable of canceling in-channel interference. The receiver includes an antenna for receiving a wireless signal comprising in-channel components and an out-of-channel component, wherein the in-channel components comprise a desired component and an in-channel interference component. A first filter of the receiver filters the wireless signal by blocking at least a portion of the out-of-channel component to produce a first signal comprising the in-channel components, and at least a second filter of the receiver filters the wireless signal by blocking at least a portion of the in-channel components to produce a second signal comprising the out-of-channel component. An in-channel interference estimator of the receiver generates an in-channel interference estimation signal based on the second signal. And a combiner of the filter combines the first signal and the second signal to at least partially cancel the in-channel interference component of the first signal.
    Type: Grant
    Filed: June 19, 2012
    Date of Patent: May 12, 2015
    Assignee: Motorola Solutions, Inc.
    Inventors: Spyros Kyperountas, Neiyer S. Correal, Qicai Shi, Charles L. Sobchak
  • Patent number: 9020023
    Abstract: The present technique relates to a reception device and a reception method which can improve equalization performance. An equalization processing unit has a time domain equalization unit which equalizes a received signal in a time domain and a frequency domain equalization unit which is provided in parallel to the time domain equalization unit and which equalizes the received signal in a frequency domain, and performs control of switching between the time domain equalization unit and the frequency domain equalization unit. The present technique can be applied to, for example, equalize a signal of data transmitted by way of single carrier transmission or data transmitted by way of multicarrier transmission.
    Type: Grant
    Filed: May 15, 2012
    Date of Patent: April 28, 2015
    Assignee: Sony Corporation
    Inventors: Katsumi Takaoka, Naoki Yoshimochi, Hidetoshi Kawauchi, Ryo Hasegawa, Hirofumi Maruyama
  • Patent number: 9014652
    Abstract: Embodiments provide a mobile communication device comprising an adaptive filter for filtering a RF signal and a controller. The adaptive filter comprises a first terminal, a second terminal, a reference terminal for providing a reference potential, a first filter structure connected in series between the first terminal and the second terminal, a second filter structure connected in series between the first terminal and the reference terminal, and a third filter structure connected in series between the second terminal and the reference terminal, wherein at least one filter structure of the first, second and third filter structures comprises at least one switchable filter element. The controller is configured to selectively activate or deactivate the at least one switchable filter element based on the RF signal or a baseband version thereof.
    Type: Grant
    Filed: June 22, 2012
    Date of Patent: April 21, 2015
    Assignee: Infineon Technologies AG
    Inventor: Winfried Bakalski
  • Patent number: 9002304
    Abstract: An analog baseband filter apparatus for a multi-mode and multi-band wireless transceiver and a method for controlling the analog baseband filter apparatus are provided. The analog baseband filter apparatus includes a plurality of Radio Frequency (RF) units, each of the plurality of RF units being for receiving RF signals of one of a plurality of frequency bands and outputting baseband signals, a plurality of filter blocks for filtering and amplifying the baseband signals, and a switching unit for connecting at least two of the plurality of RF units to at least one of the plurality of filter blocks according to a selected communication mode, wherein the at least one of the plurality of filter blocks is configured to be connected to a capacitor region of an adjacent filter block from among the plurality of filter blocks.
    Type: Grant
    Filed: April 17, 2013
    Date of Patent: April 7, 2015
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jong-Woo Lee, Shin-Chul Kim, Su-Seob Ahn, Si-Bum Jun, Byung-Ki Han
  • Publication number: 20150056939
    Abstract: The present invention provides an integrated circuit for communication, e.g., for mobile radio-frequency (RF) telecommunication, including a resonator, a main amplifier, a matching circuit, a blocker detector, a mixer circuit, and a translation filter. The resonator provides conversion from single-end to differential, and filtering function for rejecting blockers at harmonics of local oscillation signal. The blocker detector detects occurrence of blocker; according to whether blocker exists, the main amplifier amplifies differential signal of the resonator by different gains, and the mixer circuit mixes amplified signal with different numbers of mixers. The translation filter contributes to rejection of blockers closed to in-band by providing a first pass band which is translated to a second pass band by the mixer circuit. The matching circuit provides impedance match.
    Type: Application
    Filed: May 7, 2014
    Publication date: February 26, 2015
    Applicant: MediaTek Singapore Pte. Ltd.
    Inventors: Beng-Hwee Ong, EE-SZE KHOO, Osama K A Shana'a
  • Patent number: 8954025
    Abstract: A communications radio has an IF stage with an associated filter array. The array includes at least one narrowband filter whose passband is less than 3 MHz, at least one wideband filter whose passband is 3 MHz or greater, a first switch with a common pole connected to an input terminal of the array, a second switch with a common pole connected to an output terminal of the array, a third switch whose common pole is operatively connected to the input terminal, and a fourth switch whose common pole is operatively connected to the output terminal. The first and the second switches cooperate to insert a selected filter between the first and second terminals. The third and the fourth switches cooperate to insert the filter array into either a receive signal path when the radio is in a receive mode, or a transmit signal path when in a transmit mode.
    Type: Grant
    Filed: April 18, 2012
    Date of Patent: February 10, 2015
    Assignee: BAE Systems Information and Electronic Systems Integration Inc.
    Inventor: Michael S. Vogas
  • Patent number: 8954026
    Abstract: An electronic device includes an adjustable filter with a first filter element, and a second filter element coupled to the first filter element. The second filter element includes a field effect transistor (FET) including a source terminal, a drain terminal, and a gate terminal. The source terminal and the gate terminal are coupled to a reference voltage. A control circuit is coupled to the drain terminal and is configured to apply a control voltage thereto to vary a capacitance between the source and drain terminals to adjust the adjustable filter.
    Type: Grant
    Filed: November 19, 2013
    Date of Patent: February 10, 2015
    Assignee: Harris Corporation
    Inventors: Andrew Mui, Anthony C. Manicone
  • Publication number: 20150038099
    Abstract: A direct conversion receiver device may receive I and Q signals. The direct conversion receiver device may include a blind IQ balance circuit configured to balance the I and Q signals without a pilot signal, and a mixer coupled to the blind IQ balance circuit and configured to generate I and Q baseband signals using an operational frequency, the operational frequency being based upon bandwidth and modulation of the I and Q signals. The blind IQ balance circuit may include a first stage configured to generate an intermediate amplitude balanced Q signal based upon the I and Q signals, and a second stage coupled to the first stage and configured to generate phased balanced I and Q signals based upon the intermediate amplitude balanced Q signal and the I signal.
    Type: Application
    Filed: August 1, 2013
    Publication date: February 5, 2015
    Applicant: HARRIS CORPORATION
    Inventors: Timothy GILES, William Nelson FURMAN, Nicholas SHIELDS, Nathan T. PROSSER, Richard TAYLOR, Daniel E. STEPHENS
  • Patent number: 8909185
    Abstract: A method of providing frequency dependent signal attenuation. An RF input signal is split into a first signal portion and a second signal portion. Discrete time filtering, a negative group delay and bandstop filtering are applied to the first signal portion to provide a filtered signal portion. The second signal portion is applied to a component, and a component output signal portion is received from the component. The component output signal portion is combined with the filtered signal portion to provide an RF output signal having frequency dependent attenuation.
    Type: Grant
    Filed: January 28, 2013
    Date of Patent: December 9, 2014
    Assignee: Rockstar Consortium US LP
    Inventor: Mark Wyville
  • Patent number: 8892157
    Abstract: An integrated passive device with electrostatic discharge protection mechanism includes an antenna terminal for receiving and transmitting a wireless signals, a first frequency terminal for receiving and transmitting a signal with a first frequency, a first filtering circuit for filtering the wireless signal, and an electrostatic discharge protection element for conducting static electricity to ground. The first filtering circuit includes a first filtering element with a first end electrically connected to the antenna terminal, a second filtering element with a first end electrically connected to a second end of the first filtering element and a second end electrically connected to the first frequency terminal, and a third filtering element with a first end electrically connected to the second end of the first filtering element and a second end electrically connected to ground. The electrostatic discharge protection element is coupled between the second end of the first filtering element and ground.
    Type: Grant
    Filed: December 14, 2012
    Date of Patent: November 18, 2014
    Assignee: RichWave Technology Corp.
    Inventor: Kuang-Lieh Wan
  • Patent number: 8868012
    Abstract: A frequency-multiplied harmonic suppression RF circuit design method includes the steps of defining respective operating frequencies of predetermined major electronic components of the RF circuit to be designed, using these operating frequencies to calculate the values of respective frequency-multiplied harmonics and intermodulation distorsions, designing respective filters subject to the values of the frequency-multiplied harmonics and intermodulation distorsions obtained, calculating the locations of the frequency-multiplied harmonics in the RF circuit under design, installing the designed filters in the calculated locations, and testing and adjusting the installed filters.
    Type: Grant
    Filed: August 5, 2013
    Date of Patent: October 21, 2014
    Assignee: Shun-Fu Technology Corp.
    Inventor: Yung-Sheng Huang
  • Patent number: 8868019
    Abstract: A method includes receiving an input signal carrying transmitted values by a receiver, which includes a decision device that produces estimates of the transmitted values. The input signal is filtered using a forward filter to produce a forward-filtered signal, and the estimates of the transmitted values are filtered using a backward filter to produce a backward-filtered signal. The decision device is applied to a composite signal produced from the forward-filtered and backward-filtered signals, so as to produce the estimates of the transmitted values. An accuracy of the estimates of the transmitted values is assessed, and coefficients of the forward filter are adapted depending on the assessed accuracy.
    Type: Grant
    Filed: July 21, 2011
    Date of Patent: October 21, 2014
    Assignee: Siano Mobile Silicon Ltd.
    Inventors: Tomer Yablonka, Roy Oren
  • Patent number: 8867382
    Abstract: The present patent application comprises means, instructions and steps for controlling signal power by allowing a small bit error rate during burst processing comprising setting a transmit signal power granularity to be less than a current level (1210), tracking a power measurement report of at least one remote stations (1220), determining if at least one signal quality indicator has reached an upper threshold (1230), decreasing a downlink signal power if the at least one signal quality indicator reaches an upper threshold (1240), and stopping the decreasing of the downlink signal power (1260) when the at least one quality indicator reaches a lower threshold (1250).
    Type: Grant
    Filed: October 21, 2008
    Date of Patent: October 21, 2014
    Assignee: QUALCOMM Incorporated
    Inventor: Zhi-Zhong Yu
  • Patent number: 8868018
    Abstract: A system for cancellation of a reciprocal-mixing noise may comprise a down-converter mixer that may be configured to down convert a radio-frequency (RF) signal and to generate a baseband signal. The RF signal may include a desired signal and a blocker signal. A first signal path may be configured to receive the baseband signal and to generate a first signal. A second signal path may be configured to receive the baseband signal and to generate a second signal. A subtraction module may be configured to subtract the second signal from the first signal and to generate an output signal. The second signal may comprise the reciprocal-mixing noise, and the output signal may comprise the desired signal substantially free from the reciprocal-mixing noise.
    Type: Grant
    Filed: February 15, 2013
    Date of Patent: October 21, 2014
    Assignee: Broadcom Corporation
    Inventors: Mohyee Mikhemar, David Murphy, Ahmad Mirzaei, Hooman Darabi
  • Patent number: 8862081
    Abstract: Methods and apparatus for implementing a wireless communication transceiver having receive path performance diversity. The transceiver implements a plurality of signal paths that can be configured as diversity receive paths. Each of the plurality of signal paths includes a distinct RF filter. Each RF filter can be configured to provide a distinct jammer rejection profile. Each receive path also includes a jammer detector, that can be a multiple level jammer detector. Each jammer detector operates to control a level of processing gain applied to the signals in its receive path. The multiple gain scaled receive signals can be combined in a coherent combiner before being routed for further processing.
    Type: Grant
    Filed: March 17, 2009
    Date of Patent: October 14, 2014
    Assignee: Wi-LAN, Inc.
    Inventors: Todd Sutton, James Stump, Hardik Patel, Laddan Hashemian
  • Patent number: 8838033
    Abstract: Methods and systems for processing a signal with a corresponding noise profile are disclosed. Aspects of the method may comprise analyzing spectral content of the noise profile. At least one noise harmonic within the signal may be filtered based on said analyzed spectral content. The filtered signal may be amplified. The noise profile may comprise a phase noise profile. The signal may comprise at least one of a sinusoidal signal and a noise signal. At least one filter coefficient that is used to filter the at least one noise harmonic may be determined. The filtering may comprise low pass filtering. The signal may be modulated prior to filtering. The amplifying may comprise buffering. A non-linearity characteristic of the signal may be determined and a noise harmonic may be low-pass filtered within the signal based on the determined non-linearity characteristic.
    Type: Grant
    Filed: December 7, 2004
    Date of Patent: September 16, 2014
    Assignee: Broadcom Corporation
    Inventor: Shervin Moloudi
  • Patent number: 8805314
    Abstract: To implement a filter circuit with low noise and a low cutoff frequency in a smaller area, a filter circuit has a first circuit which receives an input signal supplied to an input terminal, amplifies the signal, and outputs the amplified signal to an output terminal, a first differential amplification circuit for receiving the output signal of the first circuit through a first capacitance element, a first resistance element for forming a negative feedback path between the input and output of the first differential amplification circuit, and a second resistance element for forming a negative feedback path between the output of the first differential amplification circuit and the input of the first circuit.
    Type: Grant
    Filed: October 15, 2012
    Date of Patent: August 12, 2014
    Assignee: Renesas Electronics Corporation
    Inventors: Yasuku Katsube, Takeshi Uchitomi, Yutaka Igarashi
  • Patent number: 8781430
    Abstract: Exemplary embodiments of the invention disclose receiver baseband filtering. In an exemplary embodiment, the filter device may comprise a continuous-time filter and a discrete-time filter operably coupled to the continuous time-filter. The discrete-time filter may include a passive infinite impulse response filter operably coupled between the continuous-time filter and an amplifier. The discrete-time filter may also include an active infinite impulse response filter operably coupled between an output of the amplifier and an input of the amplifier. The discrete-time filter may be configured to combine an output of the active infinite impulse response filter and an output of the passive infinite impulse response filter to form a composite signal. Furthermore, the amplifier may be configured to receive and amplify the composite signal.
    Type: Grant
    Filed: June 29, 2009
    Date of Patent: July 15, 2014
    Assignee: QUALCOMM Incorporated
    Inventor: Russell J. Fagg
  • Patent number: 8755762
    Abstract: A radio frequency (RF) receiver includes an amplifier stage, a blocking module, and a down conversion module. The amplifier stage amplifies an inbound RF signal (includes a desired component and a blocking component) to produce an amplified inbound RF signal. The blocking module generates an oscillation corresponding to a frequency of the blocking component and filters the amplified inbound RF signal based on the oscillation to substantially attenuate the blocking component and to pass, substantially unattenuated, the desired component. The down conversion module converts the desired RF signal component into a baseband or near baseband inbound signal.
    Type: Grant
    Filed: January 30, 2009
    Date of Patent: June 17, 2014
    Assignee: Broadcom Corporation
    Inventors: Mohyee Mikhemar, Hooman Darabi
  • Patent number: 8750803
    Abstract: A method, apparatus, system, and computer program product example embodiments of the invention are disclosed to reduce interference of predictive signal transmissions between wireless devices. In an example embodiment, a wireless receiver is configured to receive a composite signal, wherein the composite signal includes at least a beacon component comprising a regular beacon symbol. The wireless receiver is configured to determine from the beacon component, a predicted reception of a predicted future beacon symbol, using a known beacon transmission pattern. The wireless receiver is configured to cancel from the composite signal a future received beacon symbol, based at least partly on the predicted future beacon symbol.
    Type: Grant
    Filed: June 17, 2009
    Date of Patent: June 10, 2014
    Assignee: Nokia Corporation
    Inventor: Markus Nentwig
  • Publication number: 20140141741
    Abstract: A method for reciprocal-mixing noise cancellation may include receiving, from a first mixer, a first signal comprising a wanted signal at a first frequency and a modulated signal at a second frequency. The modulated signal may be a product of a reciprocal-mixing of an unwanted signal with a phase noise. The second frequency may be greater than the first frequency, and at least a portion of the modulated signal may overlap the wanted signal, adding a reciprocal-mixing noise to the wanted signal. Using the first signal, a narrow second signal may be generated at a third frequency, twice the second frequency. At a second mixer, the second signal may be mixed with the first signal to generate a third signal. The third signal may be subtracted from the first signal to remove a reciprocal-mixing noise and to generate the wanted signal at the first frequency without the reciprocal-mixing noise.
    Type: Application
    Filed: November 21, 2012
    Publication date: May 22, 2014
    Applicant: BROADCOM CORPORATION
    Inventors: Mohyee MIKHEMAR, David Murphy, Hooman Darabi
  • Patent number: 8718563
    Abstract: A method for processing a signal with a corresponding noise profile includes analyzing spectral content of the noise profile, filtering at least one noise harmonic within the signal based on the analyzed spectral content, and limiting the filtered signal. The noise profile may include a phase noise profile. The signal may include a sinusoidal signal and/or a noise signal. At least one filter coefficient that is used to filter the at least one noise harmonic may be determined. The filtering may include low pass filtering. The limiting may include hard-limiting of the filtered signal. A phase difference between the limited signal and a reference signal may be detected.
    Type: Grant
    Filed: September 6, 2011
    Date of Patent: May 6, 2014
    Assignee: Broadcom Corporation
    Inventor: Shervin Moloudi
  • Patent number: 8705411
    Abstract: The present patent application improves DARP by allowing multiple users on one time slot (MUROS). It comprises means, instructions and steps for combining two signals. In one example, it comprises at least one baseband modulator, a plurality of amplifiers where the signals are multiplied by a gain; at least one combiner operably connected to the amplifiers where the signals are combined; and a phase shifter where one of the signals is phase shifted with respect to the other signal. In another example; the apparatus further comprises a phase shifter operably connected to the at least one baseband modulator to provide a ?/2 phase shift between the two signals. In another example, the at least one baseband modulator comprises a BPSK baseband modulator on an I axis and a BPSK baseband modulator on a Q axis.
    Type: Grant
    Filed: October 21, 2008
    Date of Patent: April 22, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Zhi-Zhong Yu, Hassan Rafique
  • Patent number: 8687525
    Abstract: Co-channel communications methods, systems, and devices are provided. Embodiments can be utilized to allow multiple users on one time slot (MUROS). For example, a method for wireless communication by a first remote station can comprise receiving a first co-channel signal that has a first amplitude and a second co-channel signal that has a second amplitude, wherein a difference between the first amplitude and the second amplitude is less than a threshold; selecting one of the first co-channel signal and the second co-channel signal; and demodulating the selected co-channel signal. Other aspects, embodiments, and features are also claimed and described.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: April 1, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Zhi-Zhong Yu, Hassan Rafique
  • Patent number: 8676144
    Abstract: Interference in an unlicensed frequency band is spatially filtered out from received signals at a wireless device operating in the unlicensed frequency band. Energy received at a plurality of antennas of the wireless is device is analyzed to detect interference in the unlicensed frequency band. The detected interference is classified by type. Parameters for a nulling filter are generated or selected based on the type of interference detected in the received energy. During a time interval when it is expected to receive desired signals, the nulling filter is applied using the parameters to signals obtained from energy received at the plurality of antennas during the time interval.
    Type: Grant
    Filed: April 14, 2011
    Date of Patent: March 18, 2014
    Assignee: Cisco Technology, Inc.
    Inventors: Li Guo, Hang Jin, Paul J. Stager, Neil R. Diener, Matthew A. Silverman, Chandra Vaidyanathan
  • Publication number: 20140073266
    Abstract: Methods, systems, and computer readable media for wideband frequency and bandwidth tunable filtering are disclosed. According to one aspect, the subject matter described herein includes a wideband frequency and bandwidth tunable filter that splits a filter input signal into first and second input signals, modifies the first input signal to produce a first output signal, modifies the second input signal to produce a second output signal having an intermediate frequency response, and combines the first and second output signals while adjusting their relative phases and/or amplitudes to produce a filter output signal with the target frequency response. Adjustment includes splitting the second input signal into third and fourth input signals, which are modified and then combined to produce the second output signal having the intermediate frequency response.
    Type: Application
    Filed: January 18, 2013
    Publication date: March 13, 2014
    Applicant: PHYSICAL DEVICES, LLC
    Inventors: Frederick Vosburgh, Charley Theodore Wilson, III, Jonathan Ryan Wilkerson
  • Patent number: 8670738
    Abstract: An imbalance compensator includes a phase/filter mismatch correction circuit and a gain mismatch correction circuit. The phase/filter mismatch correction circuit includes an adjustable filter and a processing unit. The adjustable filter is arranged for adjusting a filter coefficient setting according to a first input signal of a first signal branch and a second input signal of a second signal branch, and generating a first compensated signal to the first signal branch according to the filter coefficient setting and the first input signal. The processing unit is arranged for processing the second input signal according to the first compensated signal and generating a second compensated signal to the second signal branch. The gain mismatch correction circuit is arranged for referring to the first and second compensated signals to configure gain compensation, and applying the configured gain compensation to one of the first and second compensated signals.
    Type: Grant
    Filed: September 19, 2011
    Date of Patent: March 11, 2014
    Assignee: Mediatek Inc.
    Inventor: Yih-Ming Tsuie
  • Patent number: 8654831
    Abstract: A signal detection apparatus detects the frequency of an input signal without using a PLL. The detection apparatus includes a first and a second orthogonalizer, a phase difference calculator and an integrator, to control the variable coefficient a1 of a band-pass filter. Information e[k]=M·sin(?) representing the phase difference ? between the input data x[k] and the output data y[k] is calculated with the first and second orthogonalizers and the phase difference calculator. The sign of e[k] is inverted and a predetermined integral calculation is performed with the integrator, and the calculated integral value is set as the coefficient a1 of the band-pass filter. Every time input data x[k] is input, the coefficient a1 is changed by reducing it when e[k]>0 and increasing it when e[k]<0. Thus, the frequency of the output signal of the band-pass filter is matched to the input signal.
    Type: Grant
    Filed: September 20, 2011
    Date of Patent: February 18, 2014
    Assignee: Daihen Corporation
    Inventor: Toyokazu Kitano
  • Patent number: 8655301
    Abstract: Systems and methods are disclosed for an electronically adjustable signal filter system, which comprises, in some embodiments, a first filter coupled to an antenna coupling network and a second filter, a power amplifier coupled to the first filter, an antenna connected to an antenna coupling network, a pilot tone generator coupled to the first filter, and a first signal source connected to the power amplifier and first filter. In some embodiments, the power amplifier amplifies the first signal, the first filter places a notch into the first signal transmitted to the antenna coupling network, the antenna coupling network combines the first signal and a second signal received from the antenna and transmits a third signal to the second filter.
    Type: Grant
    Filed: June 26, 2013
    Date of Patent: February 18, 2014
    Assignee: BlackBerry Limited
    Inventors: Alain Roussel, Charles W. T. Nicholls
  • Patent number: 8655299
    Abstract: A SAW-less receiver includes an FEM interface module, an RF to IF receiver section, and a receiver IF to baseband section. The RF to IF receiver section includes a frequency translated bandpass filter (FTBPF), an LNA, and a mixing section. The FTBPF includes a switching network and a plurality of baseband impedances. The switching network is operable to couple the plurality of baseband impedances to the FEM interface in accordance with a plurality of phase-offset RF clock signals to RF bandpass filter the inbound RF signal. The LNA amplifies the filtered inbound RF signal and the mixing section mixes the amplified inbound RF signal with a local oscillation to produce an inbound IF signal. The receiver IF to baseband section converts the inbound IF signal into one or more inbound symbol streams.
    Type: Grant
    Filed: March 30, 2011
    Date of Patent: February 18, 2014
    Assignee: Broadcom Corporation
    Inventors: Ahmad Mirzaei, Hooman Darabi
  • Patent number: 8638249
    Abstract: In accordance with an embodiment, a method includes determining an amplitude of an input signal provided by a capacitive signal source, compressing the input signal in an analog domain to form a compressed analog signal based on the determined amplitude, converting the compressed analog signal to a compressed digital signal, and decompressing the digital signal in a digital domain to form a decompressed digital signal. In an embodiment, compressing the analog signal includes adjusting a first gain of an amplifier coupled to the capacitive signal source, and decompressing the digital signal comprises adjusting a second gain of a digital processing block.
    Type: Grant
    Filed: April 16, 2012
    Date of Patent: January 28, 2014
    Assignee: Infineon Technologies AG
    Inventors: Michael Kropfitsch, Jose Luis Ceballos
  • Patent number: 8620251
    Abstract: An electronic device includes an adjustable filter with a first filter element, and a second filter element coupled to the first filter element. The second filter element includes a field effect transistor (FET) including a source terminal, a drain terminal, and a gate terminal. The source terminal and the gate terminal are coupled to a reference voltage. A control circuit is coupled to the drain terminal and is configured to apply a control voltage thereto to vary a capacitance between the source and drain terminals to adjust the adjustable filter.
    Type: Grant
    Filed: February 8, 2012
    Date of Patent: December 31, 2013
    Assignee: Harris Corporation
    Inventors: Andrew Mui, Anthony Manicone
  • Patent number: 8620244
    Abstract: An electrical component with a diversity front-end circuit that is exclusively designed to transmit received signals is disclosed. The diversity front-end circuit is capable of receiving incoming signals in at least two frequency bands simultaneously. The diversity front-end circuit includes at least two receiving paths coupled to a diversity antenna, wherein the received signals of the respective frequency band are transmitted in each receiving path.
    Type: Grant
    Filed: November 5, 2009
    Date of Patent: December 31, 2013
    Assignee: EPCOS AG
    Inventors: Christoph Roeckl, Peter Hagn, Torsten Moebes
  • Patent number: 8615213
    Abstract: In one embodiment, the present invention includes a system that having a low noise amplifier (LNA) to receive and amplify a radio frequency (RF) signal, a mixer to receive and downconvert the RF signal to a second frequency signal, a filter to receive and filter the second frequency signal, a demodulator to receive and demodulate the filtered second frequency signal to output demodulated data, and a quality detector to detect a quality of the demodulated data and output a quality indicator based on the data quality. In addition, the system can include a controller coupled to the filter to cause a state of the filter to be stored into a storage responsive to the quality indicator.
    Type: Grant
    Filed: September 12, 2011
    Date of Patent: December 24, 2013
    Assignee: Silicon Laboratories Inc.
    Inventors: Hendricus De Ruijter, Ping Xiong
  • Patent number: 8606321
    Abstract: Provided is a remote radio head receiver, including an antenna and an interference mitigation block. The antenna is configured to receive a signal. The interference mitigation block is configured to selectively pass and amplify the signal. The interference mitigation block does not include a liquefied gas cooling system.
    Type: Grant
    Filed: March 24, 2010
    Date of Patent: December 10, 2013
    Assignee: Alcatel Lucent
    Inventor: Teppo Lukkarila
  • Patent number: 8600329
    Abstract: An interfering signal canceller has a passive isolation element fed by an input signal in a primary path. A first frequency converter is in an auxiliary path and is fed by an input signal for converting the input signal to an intermediate or baseband signal. A bandpass filter is tuned to the interfering signal component for passing the interfering signal component of the converted input signal and suppressing the desired signal component. A second frequency converter/phase rotator section has a phase rotator fed by a local oscillator signal and a second frequency converter fed by the phase rotator and the bandpass filter. The second frequency converter/phase rotator section convert and phase adjust the passed the interfering signal component and the suppressed desired signal component to the predetermined band of frequencies. A combiner combines signals in the primary signal path and from the second frequency converter/phase rotator section.
    Type: Grant
    Filed: October 4, 2012
    Date of Patent: December 3, 2013
    Assignee: Raytheon Company
    Inventors: Jonathan P. Comeau, Matthew A. Morton
  • Patent number: 8600330
    Abstract: A filter arrangement for filtering a radio signal comprising at least a first filter stage is presented wherein the at least first filter stage comprises a divide stage for dividing a filter stage input signal into several signal portions. The signal portions are filtered in at least two parallel filter elements. A combine stage combines the separate filter output signals into a single filter stage output signal.
    Type: Grant
    Filed: October 5, 2011
    Date of Patent: December 3, 2013
    Assignee: KATHREIN-Werke KG
    Inventor: Lothar Schmidt
  • Patent number: 8588721
    Abstract: The dual mode receiver channel select filter includes a filter for a dual mode Bluetooth/Wireless Local Area Network (WLAN) receiver portion of a BT/WLAN transceiver. The filter is a 4th order complex filter and is digitally programmable and reconfigurable. Implemented as the channel select filter for dual-mode receivers, the filter adopts low-IF for Bluetooth and zero-IF for WLAN (IEEE 802.11b). It is based on simple active elements, such as current and voltage followers. The center frequency is digitally tuned through programming active current division networks (CDNs).
    Type: Grant
    Filed: February 8, 2012
    Date of Patent: November 19, 2013
    Assignees: King Fahd University of Petroleum and Minerals, King Abdulaziz City for Science and Technology
    Inventor: Hussain Alzaher
  • Publication number: 20130225099
    Abstract: Methods, systems, and computer readable media for wideband frequency and bandwidth tunable filtering are disclosed. According to one aspect, the subject matter described herein includes a wideband frequency and bandwidth tunable filter that splits a filter input signal into first and second input signals, modifies the first input signal to produce a first output signal, modifies the second input signal to produce a second output signal having an intermediate frequency response, and combines the first and second output signals while adjusting their relative phases and/or amplitudes to produce a filter output signal with the target frequency response. Adjustment includes splitting the second input signal into third and fourth input signals, which are modified and then combined to produce the second output signal having the intermediate frequency response.
    Type: Application
    Filed: January 18, 2013
    Publication date: August 29, 2013
    Applicant: PHYSICAL DEVICES, LLC
    Inventor: PHYSICAL DEVICES, LLC
  • Patent number: 8509716
    Abstract: A method for selecting antenna configurations in a satellite receiving system, the method comprising: selecting antenna configurations using a first mode of operation wherein frequency shift keying (“FSK”) of a frequency is implemented, or a second mode of operation wherein a DC level is implemented, and adaptively controlling a capacitor to condition a signal while the second mode is in use and removing the effects of the capacitor while the first mode is in use.
    Type: Grant
    Filed: December 14, 2005
    Date of Patent: August 13, 2013
    Assignee: Thomson Licensing
    Inventor: John James Fitzpatrick
  • Patent number: 8498584
    Abstract: Systems and methods are disclosed for an electronically adjustable signal filter system, which comprises, in some embodiments, a first filter coupled to an antenna coupling network and a second filter, a power amplifier coupled to the first filter, an antenna connected to an antenna coupling network, a pilot tone generator coupled to the first filter, and a first signal source connected to the power amplifier and first filter. In some embodiments, the power amplifier amplifies the first signal, the first filter places a notch into the first signal transmitted to the antenna coupling network, the antenna coupling network combines the first signal and a second signal received from the antenna and transmits a third signal to the second filter.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: July 30, 2013
    Assignee: Research In Motion Limited
    Inventors: Alain Roussel, Charles W. T. Nicholls
  • Patent number: 8494471
    Abstract: A receiver 1 is comprised of a first frequency changing circuit 13 for converting a received signal including two or more broadcast waves into a first intermediate frequency signal with a local oscillation, a band separation filter 14 consisting of a multistage FIR type filter for allowing bands included in the two or more broadcast waves converted into the above-mentioned first intermediate frequency signal to pass therethrough simultaneously, and a second frequency changing circuit 15 for converting the received signal which is outputted by the above-mentioned band separation filter 14 and which is limited to the above-mentioned two or more broadcast waves which the receiver desires to receive into a second intermediate frequency signal from which each of the broadcast waves can be sampled at a frequency at which the broadcast waves do not interfere with one another.
    Type: Grant
    Filed: November 5, 2009
    Date of Patent: July 23, 2013
    Assignee: Mitsubishi Electric Corporation
    Inventors: Mitsuru Takeuchi, Eiji Arita
  • Patent number: 8489056
    Abstract: The present invention is a hybrid RF-digital signal processor-based filter for multiband radio architectures, systems capable of spectrum re-farming and software defined radios It performs low-loss frequency agile multiple notch filtering at RF where a large dynamic range exists at a filter input between signals in a stopband and passband It is a frequency dependent signal attenuation apparatus having two paths connected together by directional couplers The first path comprising a component such as a delay component or duplexer The second path comprising, in series, a down converter, a digital filter, an up converter, and a bandstop filter At the output of a power amplifier, the invention can be used to attenuate spurs, or noise within bands with strict emission constraints At the input of a low noise amplifier, the invention can be used to attenuate blockers and transmitter noise outside of the receiver passband.
    Type: Grant
    Filed: November 26, 2009
    Date of Patent: July 16, 2013
    Assignee: Rockstar Consortium US LP
    Inventor: Mark Wyville
  • Patent number: 8483642
    Abstract: A SAW-less receiver includes a front end module (FEM) interface module, an RF to IF section, and an IF to baseband section. The RF to IF section includes a frequency translated bandpass filter (FTBPF), an LNA, and a mixing section. The FTBPF includes a switching network and a complex baseband filter having an offset baseband filter response. The switching network is operable to frequency translate the offset baseband filter response to an RF frequency response such that the FTBPF filters the inbound RF signal by passing, substantially unattenuated, a desired RF signal component and by attenuating an image signal component and/or an undesired signal component. The LNA amplifies the filtered inbound RF signal and the mixing section mixes the amplified inbound RF signal with a local oscillation to produce an inbound IF signal. The IF to baseband section converts the inbound IF signal into an inbound symbol stream(s).
    Type: Grant
    Filed: March 24, 2011
    Date of Patent: July 9, 2013
    Assignee: Broadcom Corporation
    Inventors: Ahmad Mirzaei, Hooman Darabi
  • Patent number: 8483644
    Abstract: The component, fully integrated onto a monolithic substrate, includes a tuner, a demodulator, and a channel decoder. The overall filtering is carried out in two parts, a baseband analog filtering and a digital Nyquist filtering removing the information of adjacent channels. It outputs a stream of MPEG data.
    Type: Grant
    Filed: May 17, 2002
    Date of Patent: July 9, 2013
    Assignee: STMicroelectronics SA
    Inventors: Pierre Busson, Bernard Louis-Gavet, Pierre-Olivier Jouffre