With Frequency Control Patents (Class 455/182.1)
  • Patent number: 10778267
    Abstract: A RF (radio frequency) signal detector includes an I/Q (in-phase/quadrature) mixer configured to convert an amplified signal, received from a low-noise amplifier, into a baseband signal having an in-phase component and a quadrature component in accordance with a LO (local oscillator) signal; a local oscillator configured to output the LO signal; a pair of baseband filters configured to output a filtered signal comprising an in-phase component and a quadrature component; a pair of 3-level slicers configured to receive the filtered signal and output a sliced signal having an in-phase component and a quadrature component; a pair of data flip flops configured to sample the sliced signal into a decision including an in-phase component and a quadrature component in accordance with a sampling clock signal; and a digital signal processor configured to determine an existence and characteristic of a component of the RF signal around a frequency of the LO signal.
    Type: Grant
    Filed: September 4, 2019
    Date of Patent: September 15, 2020
    Assignee: REALTEK SEMICONDUCTOR CORP.
    Inventors: Serkan Sayilir, Poh Boon Leong, Chia-Liang (Leon) Lin
  • Patent number: 10425129
    Abstract: Various embodiments are generally directed to techniques communicate in a cellular communication frequency range, detect a resonant signal in response to the communication in the cellular communication frequency range for cellular communication, the resonant signal to indicate presence of a contactless card. Embodiments also include enabling a near-field communication device to send a communication to the contactless card based on the detection of the resonant signal, the near-field communication device to communicate with the contactless card in a near-field communication frequency range.
    Type: Grant
    Filed: February 27, 2019
    Date of Patent: September 24, 2019
    Assignee: Capital One Services, LLC
    Inventors: Kevin Osborn, David Wurmfeld, Kevan Emmott
  • Patent number: 10045343
    Abstract: An automatic frequency control (AFC) device is provided. The AFC device includes an input module, a received signal strength indicator (RSSI) module and a carrier frequency offset (CFO) estimation module. The input module down converts and samples a received signal. The RSSI module is coupled to the input module and calculates a RSSI signal in response to the down converted and sampled received signal. The CFO estimation module is coupled to the input module and the RSSI module and calculates a moving average of binary elements of the down converted and sampled received signal. The CFO estimation module continues to calculate the moving average until the AFC converges.
    Type: Grant
    Filed: February 24, 2014
    Date of Patent: August 7, 2018
    Assignee: Agency for Science, Technology and Research
    Inventor: Xi Chen
  • Patent number: 9641368
    Abstract: The present disclosure relates to a front-end system for a radio device. In one example, a front-end system comprises a converter, the converter comprising a mixer configured for down-converting a radio frequency signal into a baseband signal by using a local oscillator signal generated by a signal generator, and characterized in that, the converter further comprises a quantizer arranged for quantizing the baseband signal into a digital signal. Further, the signal generator may be configured for generating, based on the digital signal, the local oscillator signal such that it is synchronized with the radio frequency signal.
    Type: Grant
    Filed: February 3, 2015
    Date of Patent: May 2, 2017
    Assignee: STICHTING IMEC NEDERLAND
    Inventors: Yao-Hong Liu, Wilhelmus Matthias Clemens Dolmans, Johannes Henricus Cornelus van den Heuvel
  • Patent number: 9565675
    Abstract: A linear technology radio for use in satellite communication is provided. The linear technology radio includes: a pre-amplifier to amplify a Local Oscillator (LO) reference signal; an intermediate frequency (IF) amplifier to amplify an IF signal; a frequency multiplier to multiply the LO reference signal; and a mixer to mix the amplified LO reference signal and the amplified IF signal to generate a Radio Frequency (RF) signal, wherein a frequency band of the IF signal is fixed, a frequency band of the LO reference signal is variable, and a highest frequency of the LO reference signal frequency band is less than a lowest frequency of the IF signal frequency band.
    Type: Grant
    Filed: September 26, 2014
    Date of Patent: February 7, 2017
    Assignee: Hughes Network Systems L.L.C.
    Inventors: Thomas Jackson, Rajesh Joshi, Michael Dauberman
  • Patent number: 9130573
    Abstract: Disclosed herein is a signal processing apparatus including: a voltage-controlled oscillation block having a parameter high in correlation with a filter; a measuring block configured to measure an oscillation frequency of the voltage-controlled oscillation block; and a control block configured to control the parameter of the filter by use of a measuring result of the oscillation frequency obtained by the measuring block.
    Type: Grant
    Filed: February 28, 2013
    Date of Patent: September 8, 2015
    Assignee: Sony Corporation
    Inventor: Katsuaki Takahashi
  • Patent number: 8982974
    Abstract: Receiver synchronization techniques (RST), contributing more accurate synchronization of receiver clock to OFDM composite frame combined with much faster acquisition time and better stability of the receiver clock, and phase and frequency recovery techniques, comprising a software controlled clock synthesizer (SCCS) for high accuracy phase & frequency synthesis producing synchronized low jitter clock from external time referencing signals or time referencing messages wherein SCCS includes a hybrid PLL (HPLL) enabling 1-50,000 frequency multiplication with very low output jitter independent of reference clock quality.
    Type: Grant
    Filed: February 10, 2013
    Date of Patent: March 17, 2015
    Inventor: John W Bogdan
  • Patent number: 8855589
    Abstract: A center frequency F0 of an IF filter is effectively adjusted. The IF filter filters a down-converted signal centering around the center frequency F0. A pseudo sine wave generation circuit generates a pseudo sine wave having a level change of at least two steps respectively on both positive and negative sides. The pseudo sine wave is made to pass through the IF filter by a switch circuit, and in the state, an F0 adjustment circuit adjusts the center frequency F0 in the IF filter 14 by comparing a phase of the pseudo sine wave with a phase of a signal after passing through the IF filter.
    Type: Grant
    Filed: April 23, 2013
    Date of Patent: October 7, 2014
    Assignee: Semiconductor Components Industries, LLC
    Inventors: Tomoya Kanzawa, Shinji Kurihara, Katu Horikoshi
  • Patent number: 8842787
    Abstract: A receiver is set forth that includes a tuner circuit and a converter circuit. The tuner circuit provides an analog signal corresponding to a modulated signal that is received on a selected channel. The converter circuit includes a sample clock that is used to convert the analog signal to a digital signal at a conversion rate corresponding to the frequency of the sample clock. The sample clock is selectable between at least two different clock frequencies.
    Type: Grant
    Filed: June 10, 2013
    Date of Patent: September 23, 2014
    Assignee: Marvell International Ltd.
    Inventors: King Chun Tsai, Patrick Clement, David Cousinard
  • Patent number: 8831147
    Abstract: A desired signal and interfering signal are transmitted in the same timeslot and on the same frequency using an Adaptive Quadrature Phase Shift Keying (AQPSK) modulated carrier. When the Sub-Channel Power Imbalance Ratio (SCPIR) for the AQPSK modulated carrier is large and favors the interfering signal, the interfering signal is demodulated first to obtain demodulated soft bits. The demodulated soft bits corresponding to the interfering signal are then used to estimate receiver control parameters, such as Doppler shift, frequency offset, timing error, gain, etc. Using the demodulated soft bits corresponding to the interfering signal improves the accuracy of the receiver control parameters when the SCPIR is large, and results in better overall performance of the receiver.
    Type: Grant
    Filed: March 11, 2013
    Date of Patent: September 9, 2014
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventors: Naveen Jacob, Amit Singhal
  • Patent number: 8804878
    Abstract: Modern digital signals include framing. A known sequence of transmission symbols (Unique Word (UW)) included in the transmitted signal may be used by a receiver for framing synchronization. A receiver configured to receive such a signal may be configured to detect the UW even when the signal is received with some frequency uncertainty (e.g. offset or error). A method is presented for fast acquisition of symbol and/or frame timing of a signal, including in the presence of frequency uncertainty. In some embodiments, the presented method may be used for determining a frequency offset of the received signal and a location of a unique word (UW) within a frame of the received signal, wherein said determining is based on a two-dimensional search map.
    Type: Grant
    Filed: November 5, 2012
    Date of Patent: August 12, 2014
    Assignee: Gilat Satellite Networks Ltd.
    Inventors: Uzi Ram, Michael Levitsky, Oded Bialer, Guy Levitas
  • Patent number: 8693967
    Abstract: A receiver of a GNSS system is provided. The receiver comprises two mixers and a processing circuit. The first mixer down-converts an input radio-frequency signal comprising a first GNSS signal and a second GNSS signal into a first low-frequency signal. The second mixer down-converts the input radio-frequency signal into a second low-frequency signal. The processing circuit generates at least one phase-shifted low-frequency signal according to at least the first low-frequency signal, extract signal components of the first GNSS signal by rejecting signal components of the second GNSS signal according to the second low-frequency signal and the at least one phase-shifted low-frequency signal, and extract signal components of the second GNSS signal by rejecting signal components of the first GNSS signal according to the second low-frequency signal and the at least one phase-shifted low-frequency signal. The first and second GNSS signals are situated in different frequency ranges.
    Type: Grant
    Filed: March 28, 2011
    Date of Patent: April 8, 2014
    Assignees: Mediatek Inc., National Taiwan University
    Inventors: Chi-Wei Cheng, Yueh-Hua Yu, Yi-Jan Chen
  • Publication number: 20140094132
    Abstract: Embodiments may comprise radio data system logic to enter a sleep mode and wake periodically to receive a data packet. In several embodiments, the data packet is a Radio Data System (RDS) packet and the radio data system logic is RDS logic. Further embodiments may comprise radio data system logic to process the data packet to determine a first type field and to parse the first type field to identify a first indication. In several embodiments, parsing the data packet by the radio data system logic comprises parsing the data packet to determine a program type field and parsing the program type field to identify the first indication as an emergency alert indication. In response to identifying the first indication as a trigger, many embodiments wake up NRSC-5 compliant, In-band on-channel (IBOC) radio logic to process an Active Radio message to output information associated with the first indication.
    Type: Application
    Filed: September 28, 2012
    Publication date: April 3, 2014
    Inventors: Binuraj K. Ravindran, Dongsheng Bi, Sridhar G. Sharma
  • Patent number: 8687748
    Abstract: An electronic device capable of performing automatic frequency control (AFC) to maintain frequency and timing without good received bursts, in which an oscillation unit and a baseband processing unit are provided. Wherein, the baseband processing unit computes a compensation adjustment according to a prediction model and stored information regarding a previous digital value adjustment when detecting that the baseband processing unit is incapable of controlling the oscillation unit according to received bursts from the remote communication unit, and adjusts the oscillation unit according to the determined compensation adjustment.
    Type: Grant
    Filed: November 28, 2007
    Date of Patent: April 1, 2014
    Assignee: Mediatek Inc.
    Inventors: Dung-Yun Chen, Chin-Fa Hsu, Hung-Shiun Fu, Chung-Shine Huang
  • Patent number: 8675078
    Abstract: A test system (200) for testing for missing or shorted parts within a tuner circuit includes a signal generator (202) for applying a harmonic-containing baseband time varying RF test signal to the tuner circuit. The tuner circuit is tuned to a harmonic of test signal. A detector 208 coupled to the baseband IF output of the tuner circuit detects the voltage generated in response to the applied RF test signal. A voltage measurement device (210) measures voltage detected by detector to provide an indication of the gain. Significant changes in the gain indicate missing part(s) or short circuits.
    Type: Grant
    Filed: September 19, 2012
    Date of Patent: March 18, 2014
    Assignee: Thomson Licensing
    Inventors: Lincheng Xiu, Joseph Risley Perrin, Xiaohong Ji
  • Patent number: 8634510
    Abstract: A bang-bang frequency detector with no data pattern dependency is provided. In examples, the detector recovers a clock from received data, such as data having a non-return to zero (NRZ) format. A first bang-bang phase detector (BBPD) provides first phase information about a phase difference between a sample clock and the clock embedded in the received data. A second BBPD provides second phase information about a second phase difference between the clock embedded in the received data and a delayed version of the sample clock. A frequency difference between the sample clock and the clock embedded in the received data is determined based on the first and second phase differences. The frequency difference can be used to adjust the frequency of the sample clock. A lock detector can be coupled to a BBPD output to determine if the sample clock is locked to the clock embedded in the received data.
    Type: Grant
    Filed: January 12, 2011
    Date of Patent: January 21, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Xiaohua Kong, Vannam Dang, Tirdad Sowlati
  • Patent number: 8634501
    Abstract: A method and apparatus is disclosed to process a received single stream communication signal and/or a multiple stream communication. A communications receiver is configured to receive the received communication signal. A communications receiver determines whether the received communication signal includes a single stream communication signal or a multiple stream communication signal. The communications receiver determines whether a received communication signal complies with a known single stream communications standard. The communications receiver determines whether the received communication signal complies with a known multiple stream communications standard. The communications receiver decodes the received communication signal according to the known single stream communications standard upon determining the received communication includes the signal single stream communication signal.
    Type: Grant
    Filed: June 1, 2012
    Date of Patent: January 21, 2014
    Assignee: Broadcom Corporation
    Inventor: Rohit V. Gaikwad
  • Patent number: 8634506
    Abstract: Generate a series of digital data according to a pair of differential signals received from a low speed universal serial bus. Calibrate coarsely a frequency of an oscillator according to a width of an end-of-packet of the series of digital data. And calibrate finely the frequency of the oscillator according to a width of a SYNC pattern of the series of digital data.
    Type: Grant
    Filed: October 20, 2010
    Date of Patent: January 21, 2014
    Assignee: Weltrend Semiconductor Inc.
    Inventors: Fu-Yuan Hsiao, Ke-Ning Pan
  • Patent number: 8619914
    Abstract: Provided are a receiver and a receiving method for a scalable bandwidth in a mobile station of an Orthogonal Frequency Division Multiplexing (OFDM) system. The receiving method includes the steps of: (a) filtering a received RF signal; (b) oscillating a frequency according to a center frequency control signal to output a local oscillation frequency; (c) down-converting the filtered RF signal by using the local oscillation frequency; (d) scalable-filtering the down-converted signal while adjusting a bandwidth according to a bandwidth control signal; (e) controlling gain of the scalable-filtered signal; (f) converting the gain-controlled analog signal into a digital signal by using a sampling frequency matching with a corresponding bandwidth according to an ADC control signal; and (g) demodulating the converted digital signal, outputting the center frequency control signal, the bandwidth control signal, and the ADC control signal according to control information received from an upper layer.
    Type: Grant
    Filed: November 21, 2012
    Date of Patent: December 31, 2013
    Assignees: Electronics and Telecommunications Research Institute, Samsung Electronics Co., Ltd.
    Inventors: Moon-Sik Lee, Nam-Il Kim, Hyeong-Geun Park, Il-Gyu Kim, Young-Hoon Kim, Seung-Chan Bang
  • Patent number: 8514989
    Abstract: Disclosed is a radio frequency (RF) receiver for receiving a communication channel modulated on one or more carrier frequencies. The receiver may include a gain adjustable RF amplifier, a wideband signal power measurement circuit, and control logic. The control logic may be adapted to use outputs of one or more measurement circuits to classify interfering signals based on measured signal power and spectral proximity to the one or more channel carrier frequencies, and to adjust the gain of the radio frequency amplifier based on the classification.
    Type: Grant
    Filed: August 24, 2009
    Date of Patent: August 20, 2013
    Assignee: Siano Mobile Silicon Ltd.
    Inventors: Roy Oren, Noam Lavi
  • Patent number: 8462887
    Abstract: A receiver is set forth that includes a tuner circuit and a converter circuit. The tuner circuit provides an analog signal corresponding to a modulated signal that is received on a selected channel. The converter circuit includes a sample clock that is used to convert the analog signal to a digital signal at a conversion rate corresponding to the frequency of the sample clock. The sample clock is selectable between at least two different clock frequencies.
    Type: Grant
    Filed: August 19, 2011
    Date of Patent: June 11, 2013
    Assignee: Marvell International Ltd.
    Inventors: King Chun Tsai, Patrick Clement, David Cousinard
  • Patent number: 8442451
    Abstract: Circuits, methods, and apparatus that provide isolation between receive and transmit circuits in a wireless transceiver. One example provides switches that can be included on an integrated circuit with at least portions of a wireless transceiver. These switches vary the impedance of transmitter and receiver circuits between a termination impedance and a high impedance by inserting or removing components in parallel with matching networks. Signal losses are minimized since these switches are shunt connected to input and output paths on the wireless circuit and are not connected directly in either signal path.
    Type: Grant
    Filed: June 30, 2010
    Date of Patent: May 14, 2013
    Assignee: Marvell International Ltd.
    Inventors: Chun-Geik Tan, Randy Tsang, Wayne A. Loeb
  • Patent number: 8428206
    Abstract: A method and system of fine timing synchronization for an OFDM signal. The OFDM signal is coarse timing synchronized, generating a synchronization sequence and a CFR (Channel Frequency Response). The synchronization sequence is removed. A correlation coefficient of the correlation between the CFR applied to a number of carriers and the number of carriers with different window shifts is calculated. The largest window shift corresponding to a downsampling factor is indicated by the lowest correlation coefficient greater than a threshold. The CFR is downsampled by the downsampling factor, and an inverse FFT is performed on the downsampled CFR with a reduced number of calculations reduced by the downsampling factor, transforming the CFR into a CIR. A fine timing synchronization position is determined from the CIR and is utilized by an FFT unit within an OFDM receiver to accurately receive OFDM symbols of the OFDM signal.
    Type: Grant
    Filed: March 5, 2009
    Date of Patent: April 23, 2013
    Assignee: NXP B.V.
    Inventor: Yan Li
  • Patent number: 8428543
    Abstract: A receiver arrangement with AC coupling is specified in which a filter arrangement (3) is provided in a baseband signal processing chain in a homodyne receiver and can be switched between at least two high-pass filter cut-off frequencies. In this case, a brief changeover is made to a higher cut-off frequency when varying the gain of a low-noise baseband amplifier (2), for example when the received field strength changes, during the reception mode. The described arrangement allows changes to be carried out to the gain in baseband during the normal reception mode. The present receiver is accordingly suitable for code division multiple access methods, such as those which are provided in the UMTS Standard.
    Type: Grant
    Filed: April 18, 2011
    Date of Patent: April 23, 2013
    Assignee: Intel Mobile Communications GmbH
    Inventors: Bernd Adler, Dieter Pimingsdorfer, Harald Pretl, Werner Schelmbauer
  • Patent number: 8406702
    Abstract: A clock signal generating arrangement for a communication device generates a system clock signal at an output for use as a timing reference. The clock signal generating arrangement comprises a reference clock generator for generating a reference clock signal, a main clock generator for generating a main clock signal having a greater accuracy than the reference clock signal, a clock adjust circuit coupled to the reference clock generator for generating a compensated reference clock signal to compensate for error in the reference clock signal and a clock signal selector coupled to the reference clock generator the main clock generator and the clock adjust circuit.
    Type: Grant
    Filed: March 26, 2008
    Date of Patent: March 26, 2013
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Michael Crowley, Norman Beamish, Sean Sexton, Kenneth Stebbings
  • Patent number: 8369432
    Abstract: A mobile station (14) transmits a signal after connection is established, by using the same number of subcarriers as the number of subcarriers equal to or smaller than a predetermined number used for transmitting a connection request signal (TCCH). A base station (12) detects the number of subcarriers used for transmitting the connection request signal (TCCH) (S106), and controls in accordance with the detected number of subcarriers the passband width of a bandpass filter having a passband with a variable width accommodating the predetected number of subcarriers, for separating a signal of the mobile station (14) falling within the passband from a received signal (S108).
    Type: Grant
    Filed: February 25, 2009
    Date of Patent: February 5, 2013
    Assignee: Kyocera Corporation
    Inventor: Nobuyuki Tanaka
  • Patent number: 8346194
    Abstract: A radio broadcast receiver includes a front end unit for tuning by changing a local oscillation frequency; and a control unit for managing by dividing the receiving band into a third frequency domain including a third frequency obtained by subtracting the intermediate frequency from an upper end frequency of the receiving band, a first frequency domain including a first frequency obtained by adding the intermediate frequency to a lower end frequency of the receiving band, and a second frequency domain where the first frequency domain and third frequency domain overlap, and for switching, when tuning is made across the frequency domains, the local oscillation frequency to an upper local oscillation frequency when the tuning frequency is higher than the third frequency by controlling the front end unit, and to a lower local oscillation frequency when it is lower than the first frequency by controlling the front end unit.
    Type: Grant
    Filed: August 21, 2009
    Date of Patent: January 1, 2013
    Assignee: Mitsubishi Electronic Corporation
    Inventor: Kazuhiro Nakata
  • Patent number: 8340219
    Abstract: Provided are a receiver and a receiving method for a scalable bandwidth in a mobile station of an Orthogonal Frequency Division Multiplexing (OFDM) system. The receiving method includes the steps of: (a) filtering a received RF signal; (b) oscillating a frequency according to a center frequency control signal to output a local oscillation frequency; (c) down-converting the filtered RF signal by using the local oscillation frequency; (d) scalable-filtering the down-converted signal while adjusting a bandwidth according to a bandwidth control signal; (e) controlling gain of the scalable-filtered signal; (f) converting the gain-controlled analog signal into a digital signal by using a sampling frequency matching with a corresponding bandwidth according to an ADC control signal; and (g) demodulating the converted digital signal, outputting the center frequency control signal, the bandwidth control signal, and the ADC control signal according to control information received from an upper layer.
    Type: Grant
    Filed: October 10, 2007
    Date of Patent: December 25, 2012
    Assignees: Electronics and Telecommunications Research Institute, Samsung Electronics Co., Ltd.
    Inventors: Moon-Sik Lee, Nam-Il Kim, Hyeong-Geun Park, Il-Gyu Kim, Young-Hoon Kim, Seung-Chan Bang
  • Patent number: 8335503
    Abstract: In an idle state transition from a macro mobile network to a femtocell, a mobile station looks for the femtocell to operate in a frequency band typically assigned to a macro network. For normal macro network operations, mobile stations look for base stations operating on various channels, e.g. based on hashing of respective mobile station identifiers. Femtocells generate a pilot beacon on a carrier frequency to enable mobile station acquisition, e.g. to redirect a mobile station to the operating frequency of the femtocell. To avoid the need to continually cycle or hop through all possible macro assigned carrier frequencies, pilot beacon transmissions of a particular femtocell are prioritized to correspond to the mobile station(s) expected to utilize that femtocell, e.g. by using existing network information, provisioning device information or self learning/calculating information regarding the carrier most likely to be used by any particular mobile station expected to use the femtocell.
    Type: Grant
    Filed: February 23, 2009
    Date of Patent: December 18, 2012
    Assignee: Cellco Partnership
    Inventors: Christopher Michael Desmond, Alicia Lauren Aull, Charles Albert Sanders, Michael Kearns, Eugene A. Carucci
  • Patent number: 8306491
    Abstract: In one embodiment, the present invention includes a method for determining if a frequency control instruction would cause a first capacitor bank to reach a limit and adjusting the first capacitor bank in a first direction using a calibration value and adjusting a second capacitor bank in a second direction if the first capacitor bank would reach the limit. Furthermore, the calibration value may be calculated and stored in accordance with other embodiments. In such manner, small changes in capacitance and correspondingly small changes in frequency may be effected.
    Type: Grant
    Filed: July 17, 2009
    Date of Patent: November 6, 2012
    Assignee: Silicon Laboratories Inc.
    Inventors: Lawrence Der, Dana Taipale, Scott Willingham
  • Patent number: 8284875
    Abstract: Certain embodiments of the present disclosure provide a method for frequency-domain gain control in system utilizing orthogonal frequency division multiplexing (OFDM) multiple input multiple output (MIMO). The proposed method reduces the complexity of the system while maximizing the internal accuracy of the OFDM MIMO decoder and preserving the performance of the system.
    Type: Grant
    Filed: January 15, 2010
    Date of Patent: October 9, 2012
    Assignee: Qualcomm Incorporated
    Inventors: Jong Hyeon Park, Michael L. McCloud, Brian C. Banister
  • Patent number: 8270544
    Abstract: According to one aspect of the present invention, an apparatus is provided to enable weather band radio signals to be received and processed using a digital signal processor (DSP). The DSP can include functionality to implement both frequency modulation (FM) demodulation and weather band data demodulation, i.e., specific area encoding (SAME) demodulation. In one such embodiment, soft decision samples of a SAME message can be combined, and based on a combined result, a hard decision unit can generate a bit value of weather band data.
    Type: Grant
    Filed: January 3, 2012
    Date of Patent: September 18, 2012
    Assignee: Silicon Laboratories Inc.
    Inventor: Junsong Li
  • Patent number: 8228127
    Abstract: Systems and methods for operating with oscillators configured to produce an oscillating signal having an arbitrary frequency are described. The frequency of the oscillating signal may be shifted to remove its arbitrary nature by application of multiple tuning signals or values to the oscillator. Alternatively, the arbitrary frequency may be accommodated by adjusting operation one or more components of a circuit receiving the oscillating signal.
    Type: Grant
    Filed: March 10, 2010
    Date of Patent: July 24, 2012
    Assignee: Sand 9, Inc.
    Inventors: Reimund Rebel, Klaus Juergen Schoepf, Jan H. Kuypers
  • Patent number: 8229380
    Abstract: A radio wave receiving apparatus includes: an antenna to receive a radio wave; a tuning member to allow a reception frequency of the antenna to be tuned to an intended frequency, in which tuning member a frequency characteristic is variable; a receiving member to receive a reception signal from the antenna to demodulate a modulation wave; a positive feedback member to perform a positive feedback in a signal path including the tuning member; and a switching member to turn on/off a feedback operation of the positive feedback member.
    Type: Grant
    Filed: January 27, 2012
    Date of Patent: July 24, 2012
    Assignee: Casio Computer Co., Ltd.
    Inventor: Kaoru Someya
  • Patent number: 8224276
    Abstract: A method and circuit for signal processing in a receiver that can be tuned to different carriers, the method determining the energy of the adjacent carriers N+1 and N?1, wherein a carrier N contains a signal of interest and the receiver is tuned to it, from the digital signal, in that the energy value of the carriers N+1 and N?1 determined are compared with a threshold value, and in the case where the threshold value is exceeded, a frequency shift of the signal by +?f or ??f is effected in the second method step prior to the filtering, and the frequency shift thus produced is reversed by a frequency shift by ??f or +?f prior to the filtering, and the signal is decoded.
    Type: Grant
    Filed: January 30, 2009
    Date of Patent: July 17, 2012
    Assignee: ST-Ericsson SA
    Inventors: Volker Aue, Sebastien Amiot
  • Patent number: 8160523
    Abstract: A channel detecting method executes a process for instructing a broadcast wave scan start, a process for performing tuning control, a process for starting initialization/operation of an OFDM demodulation section and starting the counting of a synchronous establishment timer unit, a process for determining that broadcasting is being conducted, a process for determining the expiration of the synchronous establishment timer unit, a process for outputting a TS signal and notifying that a broadcast parameter is being detected, a process for instructing transition to the next channel, a process for making a decision as to a final channel, a process for performing a transition operation, and a process for terminating a broadcast wave scan. When no broadcast is being conducted, a demodulation unit, an error correction unit and a decoder are not operated.
    Type: Grant
    Filed: October 16, 2007
    Date of Patent: April 17, 2012
    Assignee: Oki Semiconductor Co., Ltd.
    Inventor: Shigeru Amano
  • Patent number: 8131237
    Abstract: Disclosed is a radio wave receiving apparatus including: an antenna to receive a radio wave; a tuning member to allow a reception frequency of the antenna to be tuned to an intended frequency, in which tuning member a frequency characteristic is variable; a receiving member to receive a reception signal from the antenna to demodulate a modulation wave; a positive feedback member to perform a positive feedback in a signal path including the tuning member; and a switching member to turn on/off a feedback operation of the positive feedback member.
    Type: Grant
    Filed: June 17, 2009
    Date of Patent: March 6, 2012
    Assignee: Casio Computer Co., Ltd.
    Inventor: Kaoru Someya
  • Patent number: 8095098
    Abstract: Apparatus and methods for the management of radio frequency spectrum within a network such as a CATV network. In one aspect of the invention, an improved signal reflector apparatus adapted for use in the network is disclosed, the reflector circuit being designed to strongly reflect signal frequencies at the lower end of the CATV reverse band, and/or above the higher end of the forward band, while simultaneously allowing the rest of the reverse band and the entire forward band to pass freely through the device. This selective filtering of the spectrum allows control signals generated within a premises or private network to be directed (by reflection) to other devices within that network. A blocking element (e.g., amplifier) may also be used to provide control of the transmission and attenuation profile of the reflector apparatus. The passage of power signals such as DC or low frequency AC is also optionally provided.
    Type: Grant
    Filed: June 1, 2005
    Date of Patent: January 10, 2012
    Assignee: Time Warner Cable Inc.
    Inventors: Paul D. Brooks, Robert L. Romerein
  • Patent number: 8046015
    Abstract: A receiver is tuned to a transmission frequency of a data signal after the receiver has already locked onto a frequency carrying the data signal. A frequency offset between a locked frequency of a tuner on the receiver and the actual transmission frequency is determined by a comparator. If the frequency offset is greater than a threshold value, then the tuner is stepped to another frequency and the frequency offset is determined again. The direction of the tuning step can be determined by comparing multiple frequency offsets. An average value of multiple frequency offset measurements may also be used to determine if the tuner should retune to another frequency by comparison with the threshold value.
    Type: Grant
    Filed: August 10, 2007
    Date of Patent: October 25, 2011
    Assignee: General Instrument Corporation
    Inventors: Dipak R. Patel, Navaneetha Krishna Kankipati, Craig G. Martin
  • Patent number: 8010072
    Abstract: A technique for improving frequency synthesizer performance by frequency-compensating charge pump current in order to maintain a consistent loop bandwidth over a wide operating frequency range is described. A relationship between the capacitance value associated with a voltage controlled oscillator resonant tank and the magnitude of current pulses in a related charge pump is exploited to bound the loop bandwidth of the frequency synthesizer over both operating frequency and process variation. A control state machine generates digital coarse tune values that dynamically select a capacitance for the resonant tank, such that the voltage controlled oscillator operates within an optimal control voltage range. Each dynamically selected capacitance value is then used to determine the magnitude of current pulses in the charge pump.
    Type: Grant
    Filed: June 18, 2008
    Date of Patent: August 30, 2011
    Assignee: Atheros Communications, Inc.
    Inventor: Lalitkumar Nathawad
  • Patent number: 8005437
    Abstract: A radio transceiver device includes circuitry for radiating electromagnetic signals at a very high radio frequency both through space, as well as through wave guides that are formed within a substrate material. In one embodiment, the substrate comprises a dielectric substrate formed within a board, for example, a printed circuit board. In another embodiment of the invention, the wave guide is formed within a die of an integrated circuit radio transceiver. A plurality of transceivers with different functionality is defined. Substrate transceivers are operable to transmit through the wave guides, while local transceivers are operable to produce very short range wireless transmissions through space. A third and final transceiver is a typical wireless transceiver for communication with remote (non-local to the device) transceivers. Additionally, a multi-mode transceiver is operable to configure transmit and receive circuitry based upon transmission path.
    Type: Grant
    Filed: June 14, 2007
    Date of Patent: August 23, 2011
    Assignee: Broadcom Corporation
    Inventor: Ahmadreza Rofougaran
  • Publication number: 20110195683
    Abstract: A tuning method and tuner apparatus having a plurality of frequency conversion stages for concurrently receiving more than one channel. To avoid disturbance by oscillator pulling, a multi-phased local oscillator signal required by sub-mixers of a DAC mixer share the same timing reference. To minimize the complexity, die area and power dissipation of the local oscillation generation, a tuning offset is accepted from each of the down-conversion stages, and loss of receiver performance by the tuning offset is avoided by a control function for controlling the receiver circuit to process an increased dynamic range introduced by the tuning offset.
    Type: Application
    Filed: December 28, 2010
    Publication date: August 11, 2011
    Applicant: NXP B.V.
    Inventors: Johannes Hubertus Antonius BREKELMANS, Nenad PAVLOVIC, Jan van SINDEREN
  • Patent number: 7991378
    Abstract: Methods and apparatus for automatic frequency control in wireless receivers configured to simultaneously receive multiple carrier signals at distinct radio frequencies are disclosed. An exemplary wireless device comprises at least first and second radio front-end circuits configured to receive first and second wireless communication signals transmitted via first and second radio-frequency carriers at distinct first and second radio frequencies, respectively, a control processor configured to designate a master carrier signal and a slave carrier signal from among the received wireless communication signals, and a frequency error estimation circuit configured to estimate a first receiver frequency error using the received master carrier signal. The control processor is further configured to calculate a second receiver frequency error from the first receiver frequency error, for use in compensating one or more receiver processes performed on the slave carrier signal.
    Type: Grant
    Filed: August 26, 2008
    Date of Patent: August 2, 2011
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Bengt Lindoff, Bo Bernhardsson, Fredrik Nordström
  • Patent number: 7970361
    Abstract: A user equipment (UE) without service in a communication system measures the radio-frequency (RF) power in a bandwidth received by the UE on the possible downlink carriers in a frequency band that is supported by the UE. The bandwidth is typically the bandwidth of communication channels in the communication system. If the UE supports more than one frequency band, the UE may scan more than one of those frequency bands. The UE processes the measurement results with a noise-reducing enhancement technique, such as a median filter, and then examines the processed results for a particular spectral shape, e.g., a shape that corresponds to a cell signal.
    Type: Grant
    Filed: November 28, 2007
    Date of Patent: June 28, 2011
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Ali G. Nader, Béla Rathonyi
  • Patent number: 7929937
    Abstract: A system and method for blind estimation of carrier frequency offsets (CFOs) and separation of user signals in wireless communications systems are provided. Blind estimation of CFOs (i.e., without knowledge of the conditions of the transmitter or the transmission medium/channel) is carried out in order to improve reception quality by a wireless communications device. A received RF signal is over-sampled by a pre-defined over-sampling factor, and polyphase components are extracted from the over-sampled signal. The polyphase components are used to construct a virtual receiver output matrix, e.g., a model of the received signal and its associated output matrix. System response conditions are blindly estimated by applying a blind system estimation algorithm to the virtual receiver output matrix.
    Type: Grant
    Filed: October 24, 2007
    Date of Patent: April 19, 2011
    Assignee: The Trustees of Princeton University
    Inventors: Visa Koivunen, Athina Petropulu, H. Vincent Poor, Yuanning Yu
  • Patent number: 7929928
    Abstract: A frequency phase correction system and method are described that provides a receiver with a greater ability to lock onto relatively weak radio frequency signals by determining and estimating an amount of frequency error in a local frequency reference of the receiver, and using the error estimate to maintain frequency coherence with a received signal, thereby allowing tracking over a longer period of time, enabling longer integration times to capture weaker signals without losing frequency coherence.
    Type: Grant
    Filed: November 24, 2004
    Date of Patent: April 19, 2011
    Assignee: SiRF Technology Inc.
    Inventors: Daniel Babitch, Steven A. Gronemeyer, Lionel Garin, Ashutosh Pande, Leon Kuo-Liang Peng, Gengsheng Zhang, Nicolas Patrick Vantalon
  • Patent number: 7929936
    Abstract: A receiver arrangement with AC coupling is specified in which a filter arrangement (3) is provided in a baseband signal processing chain in a homodyne receiver and can be switched between at least two high-pass filter cut-off frequencies. In this case, a brief changeover is made to a higher cut-off frequency when varying the gain of a low-noise baseband amplifier (2), for example when the received field strength changes, during the reception mode. The described arrangement allows changes to be carried out to the gain in baseband during the normal reception mode. The present receiver is accordingly suitable for code division multiple access methods, such as those which are provided in the UMTS Standard.
    Type: Grant
    Filed: June 21, 2002
    Date of Patent: April 19, 2011
    Assignee: Infineon Technologies AG
    Inventors: Bernd Adler, Dieter Pimingsdorfer, Harald Pretl, Werner Schelmbauer
  • Patent number: 7920837
    Abstract: Methods and systems for wireless communication are disclosed and may include band-limiting a wireless signal utilizing a programmable bandpass filter, generating a first signal by undersampling utilizing a clock signal and generating a second signal by undersampling the signal utilizing a delayed version of the clock signal, which may then be subtracted from the first signal. The filter may comprise a microstrip or a coplanar waveguide bandpass filter. The delay may be variable, and may be defined as an inverse of a frequency difference between the desired channel and a blocker signal. The bandwidth of the filter may be centered at the desired channel. The clock signal may be generated at a frequency which may be an integer sub-harmonic of the desired channel, and may be greater than twice a bandwidth of the filter. The delay may be controlled by a programmable delay circuit, which may comprise CMOS inverters.
    Type: Grant
    Filed: September 28, 2007
    Date of Patent: April 5, 2011
    Assignee: Broadcom Corporation
    Inventors: Ahmadreza Rofougaran, Maryam Rofougaran
  • Patent number: 7805123
    Abstract: A technique of frequency hopping communication capable of high-speed switching of a plurality of signals having ultra-wide band 528 MHz bandwidth at high-speed and setting and switching a band center frequency and the number of bands arbitrary is provided. A radio transceiver has a frequency hopping communication function of UWB system for switching the ultra wide band signal. In the device, high-speed frequency hopping is realized by controlling an SSB mixer in a local oscillator circuit and switching the frequency of a DDS. The device sets NCO data to the DDS and switches a quadrature phase signal of an output, and switches a signal input of an input terminal of the SSB mixer by a control of a phase switching switch. One of a sum component and a difference component of a mixture of first and second quadrature phase signals is outputted from the output terminal of the SSB mixer.
    Type: Grant
    Filed: April 20, 2007
    Date of Patent: September 28, 2010
    Assignee: Renesas Technology Corp.
    Inventors: Yoshikazu Sugiyama, Isao Ikuta, Yusaku Katsube
  • Patent number: 7805118
    Abstract: A satellite receiving system (200, 300) and a method for adjusting a satellite receiving system include an input (113); a first oscillator (106) with theoretical frequency (FOSC1) and real frequency (FOSC1?), a first frequency mixer (105) delivering a signal at a first intermediate frequency (F2), a second oscillator (302) with frequency (FOSC2), a second frequency mixer (301) delivering a signal at a second intermediate frequency (FOUT), a microcontroller (202), which controls a real frequency (FVCO) of the second oscillator, and an output (110). An external signal (112) at a determined frequency (F1) is supplied to the input (113). A nominal value (FOSC2) of the frequency of the second oscillator is determined as a function of the input frequency (F1), the theoretical frequency (FOSC1) of the first oscillator and the second intermediate frequency (FOUT). The frequency of the second oscillator is controlled, via the microcontroller, at the determined nominal value.
    Type: Grant
    Filed: March 16, 2005
    Date of Patent: September 28, 2010
    Assignee: STMicroelectronics SA
    Inventors: Jean-Yves Couet, Anis Ben Abdallah