With Frequency Conversion Patents (Class 455/190.1)
  • Patent number: 9685931
    Abstract: Certain aspects of the present disclosure provide circuits for generating high accuracy millimeter wave or radio frequency (RF) wideband in-phase (I) and quadrature (Q) oscillating signals having acceptable amplitude and phase mismatch over process, voltage, and temperature (PVT) variations with reduced cost, area, and power consumption. In one example apparatus, a polyphase filter having a first stage and a second stage is provided. Each stage comprises resistive elements and capacitive elements. Certain aspects of the present disclosure provide for intentional resistive and/or capacitive value mismatch between the resistive or capacitive values of one or multiple stages such that the phase mismatch between the resulting I and Q signals may be reduced without degrading the amplitude mismatch. Certain aspects of the present disclosure provide for replacing the resistive elements in at least one stage with transistors operating in the triode region, where the on-resistance is controlled by a feedback network.
    Type: Grant
    Filed: August 28, 2014
    Date of Patent: June 20, 2017
    Assignee: QUALCOMM Incorporated
    Inventors: Mazhareddin Taghivand, Tong Zhang, Mohammad Mahdi Ghahramani
  • Patent number: 9509351
    Abstract: A method includes providing a highly linear front end in a Radio Frequency (RF) receiver, implementing a high Effective Number of Bits (ENOB) Analog to Digital Converter (ADC) circuit in the RF receiver, and sampling, through the high ENOB ADC circuit, at a frequency having harmonics that do not coincide with a desired signal component of an input signal of the RF receiver to eliminate spurs within a data bandwidth of the RF receiver. The input signal includes the desired signal component and an interference signal component. The interference signal component has a higher power level than the desired signal component. The method also includes simultaneously accommodating the desired signal component and the interference signal component in the RF receiver based on an increased dynamic range of the RF receiver and the high ENOB ADC circuit provided through the highly linear front end and the high ENOB ADC circuit.
    Type: Grant
    Filed: July 27, 2012
    Date of Patent: November 29, 2016
    Assignee: TAHOE RF SEMICONDUCTOR, INC.
    Inventors: Michael Joseph Shaw, Jonathan Lee Kennedy, Darrell Lee Livezey, Joy Laskar
  • Patent number: 9478204
    Abstract: A sub-harmonic mixer comprising first and second input ports, and an output port, and arranged to output products of signals applied at the input ports. The sub-harmonic mixer comprises a first stage a second stage arranged in series with each other, with the input ports of the sub-harmonic mixer being input ports of the first stage, and the output port of the sub-harmonic mixer being an output port of the second stage. An output port of the first stage is connected to an input port of the second stage. The first stage is arranged to generate a fundamental product and a first third order intermodulation distortion product in-phase with each other. The second stage is arranged to generate a second third order intermodulation distortion product in anti-phase to the fundamental product generated by the second stage.
    Type: Grant
    Filed: September 4, 2012
    Date of Patent: October 25, 2016
    Assignee: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
    Inventor: Mingquan Bao
  • Patent number: 9236930
    Abstract: Systems and techniques for management of an antenna tuning frequency range. Frequency coverage needed for an antenna used in a portable communications device in a wireless communication network is determined based on communication protocols being used, with an active tuner being connected to a passively tuned antenna when a different frequency range is called for and with the active tuner being effectively isolated when only the range provided by the passively tuned antenna is needed to reduce the risk of RF mixing or intermodulation.
    Type: Grant
    Filed: June 13, 2013
    Date of Patent: January 12, 2016
    Assignee: Nokia Technologies Oy
    Inventors: Niels Bonne Larsen, Kevin Li
  • Patent number: 9037414
    Abstract: A system and method of identifying changes utilizing radio frequency polarization includes receiving a reflected and/or transmitted polarized radio frequency signal at a receiver, filtering, amplifying and conditioning the received signal, converting the received signal from an analog format to a digital format, processing the digital signal to elicit a polarization mode dispersion feature of the received signal, and comparing the polarization mode dispersion features to a known calibration to detect a change in a characteristic of the target object.
    Type: Grant
    Filed: January 13, 2012
    Date of Patent: May 19, 2015
    Assignee: University of Notre Dame du Lac
    Inventor: Thomas G. Pratt
  • Patent number: 9037107
    Abstract: A communication device is disclosed. The device may be in particular a radio transmitter and a receiver that can operate with low power consumption and with improved interference rejection, therefore particularly suitable for use in low-power communication systems, such as wireless sensor networks and wireless body area networks. In one aspect, multiple frequency tones (carriers) are used to carry information from the transmitter, such that a RF signal having multiple radio frequency components is produced and transmitted. In the receiver, an envelope detector is still the RF down-converter. After down-converting intermodulation components are extracted containing amplitude, phase and frequency information of the multiple radio frequency components. This allows the desired signal (the baseband information) to be distinguished from the carriers and unwanted interference.
    Type: Grant
    Filed: November 16, 2012
    Date of Patent: May 19, 2015
    Assignee: Stichting IMEC Nederland
    Inventors: Xiongchuan Huang, Ruben De Francisco Martin, Guido Dolmans
  • Patent number: 8948708
    Abstract: Radio-frequency (RF) apparatus includes receiver analog circuitry that receives an RF signal and provides at least one digital signal to receiver digital circuitry that functions in cooperation with the receiver analog circuitry. The receiver analog circuitry and the receiver digital circuitry are partitioned so that interference effects between the receiver analog circuitry and the receiver digital circuitry tend to be reduced.
    Type: Grant
    Filed: May 21, 2014
    Date of Patent: February 3, 2015
    Assignee: Silicon Laboratories Inc.
    Inventors: Donald A. Kerth, Richard T. Behrens, Jeffrey W. Scott, G. Diwakar Vishakhadatta, G. Tyson Tuttle, Vishnu Srinivasan
  • Patent number: 8849226
    Abstract: A wireless receiver designed to conform to the standard IEEE 802.15.4. The receiver comprises an analog front-end and a digital decoder. The analog components of the front end include one or more amplifiers and an analog-to-digital converter (ADC). The digital decoder receives the output of the ADC and demodulates it in a demodulator which is driven at an a chip frequency by an internal or external clock. The demodulator comprises a sampler operable to sample the digital signal at a sampling frequency and a correlation unit operable to process a set of bits, referred to as a chip code, in the sampled digitized signal and output therefrom a set of correlation values. The set of correlation values is an indicator of likely mapping between the chip code that has been processed and a set of possible chip codes defined according to the standard. The demodulator further comprises a symbol selection unit and a frequency correction unit.
    Type: Grant
    Filed: August 11, 2010
    Date of Patent: September 30, 2014
    Assignee: Cascoda Limited
    Inventor: Wolfgang Bruchner
  • Patent number: 8843080
    Abstract: Radio-frequency (RF) apparatus includes receiver analog circuitry that receives an RF signal and provides at least one digital signal to receiver digital circuitry that functions in cooperation with the receiver analog circuitry. The receiver analog circuitry and the receiver digital circuitry are partitioned so that interference effects between the receiver analog circuitry and the receiver digital circuitry tend to be reduced.
    Type: Grant
    Filed: December 31, 2012
    Date of Patent: September 23, 2014
    Assignee: Silicon Laboratories Inc.
    Inventors: Donald Kerth, Richard Behrens, Jeffrey Scott, G. Diwakar Vishakhadatta, G. Tyson Tuttle, Vishnu Srinivasan
  • Patent number: 8818310
    Abstract: The noise response in a passive mixer circuit is improved by discharging the switching transistors in the mixer circuit in an appropriate time slot prior to activation. In addition to improving the noise response, tilt in conversion gains and linearity can be reduced. A passive mixer circuit includes bypass switches arranged in proximity to the switching transistors that make up the mixer core. These bypass switches, which are activated in intervals just prior to the active intervals of their neighboring switching transistors, discharge to ground accumulated charges on the switching transistors or on reactive components around switches.
    Type: Grant
    Filed: June 27, 2012
    Date of Patent: August 26, 2014
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventor: Reza Bagger
  • Patent number: 8755760
    Abstract: A radio receiver including a sampling unit, a provider, an arithmetic operation unit, an estimator, and a converter. The sampling unit samples a baseband signal transmitted from the radio transmitter, at a fractional multiple of a symbol rate, and generates fractional-multiple-sampling data. The provider provides reference data in which the known symbol sequence arranged in a frame by the radio transmitter is interpolated at a rate of the fractional multiple. The arithmetic operation unit performs an arithmetic operation for evaluation data in which the degree of consistency in waveform between the fractional-multiple-sampling data and the reference data is evaluated. The estimator estimates a reference timing from a shift amount at which the evaluation data shows the maximum degree of consistency in waveform. The converter converts the fractional-multiple-sampling data by using the reference timing as a reference thereby recovering the data having the symbol rate.
    Type: Grant
    Filed: September 13, 2012
    Date of Patent: June 17, 2014
    Assignee: International Business Machines Corporation
    Inventors: Yasunao Katayama, Daiju Nakano
  • Patent number: 8744389
    Abstract: A high-speed transmitter and receiver are provided. In one embodiment, a transmitter comprises a baseband processor structured to receive data and to convert the data into a multiplicity of high and low signal values, with each high and low signal value having a first timing interval. A local oscillator generates a clock signal at a second timing interval and a digital circuit combines the high and low signal values with the clock signal to produce a transmission signal directly at a transmission frequency. A receiver is configured to receive the signal. This Abstract is provided for the sole purpose of complying with the Abstract requirement rules that allow a reader to quickly ascertain the subject matter of the disclosure contained herein. This Abstract is submitted with the explicit understanding that it will not be used to interpret or to limit the scope or the meaning of the claims.
    Type: Grant
    Filed: October 12, 2011
    Date of Patent: June 3, 2014
    Assignee: Intellectual Ventures Holding 73 LLC
    Inventors: Ismail Lakkis, Yasaman Bahreini, John Santhoff
  • Patent number: 8725085
    Abstract: A front-end module (FEM) includes first and second frequency band power amplifiers (PA), first and second frequency band receiver-transmitter (RX-TX) isolation modules, and an antenna interface unit. The PAs are operable to amplify first and second frequency band outbound RF signals, respectively. The RX-TX isolation modules are operable to isolate first and second frequency band inbound RF signals from first and second frequency band outbound RF signals in accordance with first and second frequency band isolation tuning signal, respectively. The antenna interface unit is operably tuned in accordance with an antenna interface tuning signal to output at least one of the first frequency band outbound RF signal and the second frequency band outbound RF signal and to receive at least one of the first frequency band inbound RF signal and the second frequency band inbound RF signal.
    Type: Grant
    Filed: March 30, 2011
    Date of Patent: May 13, 2014
    Assignee: Broadcom Corporation
    Inventors: Hooman Darabi, Ahmadreza (Reza) Rofougaran
  • Publication number: 20140128015
    Abstract: A direct sampling tuner includes a low noise amplifier and an optional dynamically configurable band pass filter coupled to the lose noise amplifier. The optional filter is configured to pass a selected band of channels. The tuner further includes a relatively high accuracy, multi-bit analog-to-digital converter (“ADC”) coupled to the LNA or to the optional dynamically configurable band pass filter. The ADC operates at greater than about twice a frequency of a sampled signal. The ADC directly samples the spectrum of the selected channels at the Nyquist rate, thus avoiding image problems presented by conventional tuners.
    Type: Application
    Filed: January 13, 2014
    Publication date: May 8, 2014
    Applicant: Broadcom Corporation
    Inventor: Leonard DAUPHINEE
  • Patent number: 8693973
    Abstract: A coplanar waveguide (CPW) based subharmonic mixer working at 670 GHz using GaAs Schottky diodes. One example of the mixer has a LO input, an RF input and an IF output. Another possible mixer has a LO input, and IF input and an RF output. Each input or output is connected to a coplanar waveguide with a matching network. A pair of antiparallel diodes provides a signal at twice the LO frequency, which is then mixed with a second signal to provide signals having sum and difference frequencies. The output signal of interest is received after passing through a bandpass filter tuned to the frequency range of interest.
    Type: Grant
    Filed: May 2, 2012
    Date of Patent: April 8, 2014
    Assignee: California Institute of Technology
    Inventors: Goutam Chattopadhyay, Erich T. Schlecht, Choonsup Lee, Robert H. Lin, John J. Gill, Seth Sin, Imran Mehdi
  • 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: 8634786
    Abstract: Provision of gigabit-rate data transmission over wireless radio links, using carrier frequencies in the millimeter-wave range (>30 GHz). More specifically, a circuit for detection of amplitude-shift keyed (ASK) or other amplitude modulations (AM) which can be easily incorporated into an integrated circuit receiver system is described, making the receiver capable of supporting both complex IQ modulation schemes and simpler, non-coherent on-off or multiple-level keying signals. Several novel radio architectures are also described which, with the addition of a frequency discriminator network, have the capability of handling frequency shift keyed (FSK) or other frequency modulations (FM), as well as AM and complex IQ modulation schemes. These radio architectures support this wide variety of modulations by efficiently sharing detector hardware components.
    Type: Grant
    Filed: August 20, 2012
    Date of Patent: January 21, 2014
    Assignee: International Business Machines Corporation
    Inventors: Troy J. Beukema, Scott K. Reynolds
  • Patent number: 8634787
    Abstract: Provision of gigabit-rate data transmission over wireless radio links, using carrier frequencies in the millimeter-wave range (>30 GHz). More specifically, a circuit for detection of amplitude-shift keyed (ASK) or other amplitude modulations (AM) which can be easily incorporated into an integrated circuit receiver system is described, making the receiver capable of supporting both complex IQ modulation schemes and simpler, non-coherent on-off or multiple-level keying signals. Several novel radio architectures are also described which, with the addition of a frequency discriminator network, have the capability of handling frequency shift keyed (FSK) or other frequency modulations (FM), as well as AM and complex IQ modulation schemes. These radio architectures support this wide variety of modulations by efficiently sharing detector hardware components.
    Type: Grant
    Filed: August 20, 2012
    Date of Patent: January 21, 2014
    Assignee: International Business Machines Corporation
    Inventors: Troy J. Beukema, Scott K. Reynolds
  • Patent number: 8599312
    Abstract: According to one aspect, a mixed-signal tuner for analog and digital TV reception incorporates a demodulator for analog TV, employing various features for resolving limitations of the analog circuitry and for achieving compatibility with various global TV standards. Such features, which may be present in one or more embodiments, include the use of a variable sample rate in all digital clocks for frequency planning, and use of a microcontroller (MCU) to control various circuitry of the tuner.
    Type: Grant
    Filed: October 22, 2009
    Date of Patent: December 3, 2013
    Assignee: Silicon Laboratories Inc.
    Inventors: Alan Hendrickson, David Trager, Mitch Reid, Li Gao, John Khoury
  • Patent number: 8543079
    Abstract: Provision of gigabit-rate data transmission over wireless radio links, using carrier frequencies in the millimeter-wave range (>30 GHz). More specifically, a circuit for detection of amplitude-shift keyed (ASK) or other amplitude modulations (AM) which can be easily incorporated into an integrated circuit receiver system is described, making the receiver capable of supporting both complex IQ modulation schemes and simpler, non-coherent on-off or multiple-level keying signals. Several novel radio architectures are also described which, with the addition of a frequency discriminator network, have the capability of handling frequency shift keyed (FSK) or other frequency modulations (FM), as well as AM and complex IQ modulation schemes. These radio architectures support this wide variety of modulations by efficiently sharing detector hardware components.
    Type: Grant
    Filed: August 20, 2012
    Date of Patent: September 24, 2013
    Assignee: International Business Machines Corporation
    Inventors: Troy J. Beukema, Scott K. Reynolds
  • Patent number: 8514915
    Abstract: Coverage for a wireless network is improved using a frequency shifting scheme. A wireless signal in a frequency band is shifted to another band, and carried in the shifted band to another location where the signal is shifted back to the original frequency band. The frequency shifting may utilize frequency shifting schemes such as mixer/filter and heterodyne. The wireless signal can be frequency shifted by converting it to other representing signals (such as I/Q components) and forming the frequency-shifted signal from the representations. The transmission medium may use dedicated wiring or existing service wiring in a residence or building, including LAN, telephone, AC power and CATV wiring. The system may be enclosed as a stand-alone unit, housed in integrated form as part of a service outlet or as a snap-on/plug-in module.
    Type: Grant
    Filed: April 5, 2012
    Date of Patent: August 20, 2013
    Assignee: Corning MobileAccess Ltd
    Inventors: Yehuda Binder, Ami Hazani
  • Patent number: 8478219
    Abstract: A down-conversion module for a heterodyne receiver comprises a first mixer circuit, a second mixer circuit and an interconnection. The first mixer circuit includes first and second differential control terminals and is arranged to produce a first down-converted differential voltage signal at a first down-converted frequency as a function of a first RF differential input signal applied to the first differential control terminals and of a first RF differential reference frequency signal applied to the second differential control terminals.
    Type: Grant
    Filed: July 25, 2008
    Date of Patent: July 2, 2013
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Saverio Trotta, Ralf Reuter
  • Patent number: 8427586
    Abstract: The tuner comprises an RF input for receiving a high frequency signal, a downconverter including a mixer for downconverting the high frequency signal, an IF filter coupled to an output of the mixer, an SAW filter coupled to an output of the IF filter and a gain-controlled IF amplifier coupled to an output of the SAW filter for providing an amplified IF signal for a subsequent demodulator. The IF filter includes a controllable damping stage which is in particular usable for improving the noise performance of the tuner. The tuner is designed in a preferred embodiment for reception of analog and digital television signals and the controllable damping stage provides a damping in case of reception of an analog television signal for improving a signal/noise ratio of the analog television signal. The damping stage comprises for example a switching stage utilizing one or several varactor diodes as damping elements.
    Type: Grant
    Filed: January 27, 2009
    Date of Patent: April 23, 2013
    Assignee: Thomson Licensing
    Inventors: Kim Suan Pang, Vinod Menon
  • Patent number: 8417192
    Abstract: Systems and methods are disclosed for transmitting and receiving RF signals. An exemplary RF transceiver includes a signal generator, a frequency multiplier circuit, a receiver circuit, a transmitter circuit, and a switching device. The signal generator is configured to output a first signal and a second signal. The first signal comprises a local oscillator signal, and a frequency of the second signal is derived from a frequency of the first signal. The frequency multiplier circuit is configured to upconvert the output of the signal generator by frequency multiplication. The receiver circuit is configured to process a received signal using an upconverted first signal, and the transmitter circuit is configured to provide an upconverted second signal to a transmitter channel. The switching device is configured to provide the upconverted first signal to the receiver circuit and the upconverted second signal to the transmitter circuit.
    Type: Grant
    Filed: August 29, 2008
    Date of Patent: April 9, 2013
    Assignee: Lockheed Martin Corporation
    Inventors: Vernon T. Brady, Scott A. Faulkner
  • Patent number: 8401512
    Abstract: A MMIC (microwave monolithic integrated circuit) based FET mixer and method for the same is provided. In particular, adjacent transistors, such as FETs (field effect transistors) share terminals reducing physical layout separation and interconnections. A smaller die size is realized with the improved system geometry herein provided.
    Type: Grant
    Filed: April 8, 2010
    Date of Patent: March 19, 2013
    Assignee: Viasat, Inc.
    Inventor: Kenneth V. Buer
  • Patent number: 8391815
    Abstract: A radio receiver including a sampling unit, a provider, an arithmetic operation unit, an estimator, and a converter. The sampling unit samples a baseband signal transmitted from the radio transmitter, at a fractional multiple of a symbol rate, and generates fractional-multiple-sampling data. The provider provides reference data in which the known symbol sequence arranged in a frame by the radio transmitter is interpolated at a rate of the fractional multiple. The arithmetic operation unit performs an arithmetic operation for evaluation data in which the degree of consistency in waveform between the fractional-multiple-sampling data and the reference data is evaluated. The estimator estimates a reference timing from a shift amount at which the evaluation data shows the maximum degree of consistency in waveform. The converter converts the fractional-multiple-sampling data by using the reference timing as a reference thereby recovering the data having the symbol rate.
    Type: Grant
    Filed: November 17, 2010
    Date of Patent: March 5, 2013
    Assignee: International Business Machines Corporation
    Inventors: Yasunao Katayama, Daiju Nakano
  • 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: 8249542
    Abstract: This disclosure addresses providing gigabit-rate data transmission over wireless radio links, using carrier frequencies in the millimeter-wave range (>30 GHz). More specifically, a circuit for detection of amplitude-shift keyed (ASK) or other amplitude modulations (AM) which can be easily incorporated into an integrated circuit receiver system is described, making the receiver capable of supporting both complex IQ modulation schemes and simpler, non-coherent on-off or multiple-level keying signals. Several novel radio architectures are also described which, with the addition of a frequency discriminator network, have the capability of handling frequency shift keyed (FSK) or other frequency modulations (FM), as well as AM and complex IQ modulation schemes. These radio architectures support this wide variety of modulations by efficiently sharing detector hardware components.
    Type: Grant
    Filed: July 22, 2008
    Date of Patent: August 21, 2012
    Assignee: International Business Machines Corporation
    Inventors: Troy J. Beukema, Scott K. Reynolds
  • Patent number: 8184681
    Abstract: Systems, methods and apparatus for improving the coverage of a wireless network based on frequency shifting scheme. A wireless signal in a frequency band is shifted to another distinct band, and carried in the shifted band, using wired or wireless mediums to another location, wherein the wireless signal is shifted back to the original frequency band. The frequency shifting may make use of a conventional frequency shifting schemes such as mixer/filter and heterodyne. In one embodiment the wireless signal is frequency shifted by converting it to other representing signals (such as I/Q components) and forming the frequency-shifted signal from the representations. The system is may be used to increase in-door or outdoor coverage, as well as bridging between in-door and outdoor networks. The medium may use dedicated wiring or existing service wiring in a residence or building, including LAN, telephone, AC power and CATV wiring.
    Type: Grant
    Filed: September 17, 2010
    Date of Patent: May 22, 2012
    Assignee: Corning MobileAccess Ltd
    Inventors: Yehuda Binder, Ami Hazani
  • Publication number: 20120083231
    Abstract: Noise in an audio output is reduced even if a mixing signal leaks to another tuner. A broadcast wave is received from a broadcast station by an antenna to which a mixing signal is mixed by a mixer to obtain an IF signal and demodulated by a demodulator. An oscillator outputs a mixing signal having a frequency difference of at least a barely audible frequency within an audio frequency band from any broadcast station center frequency allocated at a predetermined frequency spacing, the mixing signal is mixed with the signal received by the antenna, and the IF signal is obtained.
    Type: Application
    Filed: September 23, 2011
    Publication date: April 5, 2012
    Applicant: ON SEMICONDUCTOR TRADING, LTD.
    Inventor: Shinji Kurihara
  • Patent number: 8150349
    Abstract: An apparatus and method for audio conversion is provided to upgrade the resolution of transmission frequency of an FM (frequency modulation) transmitter and reduce the size of the FM transmitter by applying frequency coarse tune and fine tune. The apparatus comprises a digital FM modulator, a digital frequency synthesizer, a signal converter, and an analog frequency converter. The digital FM modulator modulates a digital audio input signal into a first digital audio signal. The digital frequency synthesizer converts the first digital audio signal into a second digital audio signal, whose frequency is determined according to a first frequency conversion parameter. The signal converter converts the second digital audio signal into an analog audio signal. The analog frequency converter generates an audio transmission signal with a predetermined frequency according to a second clock signal and the analog audio signal while the second clock signal is generated according to a first clock signal.
    Type: Grant
    Filed: June 27, 2008
    Date of Patent: April 3, 2012
    Assignee: MStar Semiconductor, Inc
    Inventor: ShouFang Chen
  • Patent number: 8145162
    Abstract: A tuner device includes tuner circuits, where each of the tuner circuits includes a radio frequency amplifier amplifying a radio frequency signal of a transmitted broadcast wave, a frequency mixing circuit performing frequency conversion for the transmitted radio frequency signal, and a local oscillation circuit transmitting a local oscillation signal to the frequency mixing circuit, wherein the local oscillation circuit includes, at least, a reference signal source, a first frequency divider, and a second frequency divider, oscillates a local oscillation signal having a local oscillation frequency, and makes a difference between local oscillation frequencies of the tuner circuits, the difference being generated when the tuner circuits receive the broadcast waves of the same frequency, greater than or equal to a predetermined value.
    Type: Grant
    Filed: October 27, 2009
    Date of Patent: March 27, 2012
    Assignee: Sony Corporation
    Inventor: Mitsuru Ikeda
  • Patent number: 8145177
    Abstract: A receiving apparatus includes: a frequency conversion portion that has at least a mixer that down-converts a frequency of a reception radio-frequency signal by mixing the radio-frequency signal and an output from a voltage-controlled oscillator and outputs the down-converted radio-frequency signal; and a resistor element that has a resistance value to set a DC bias voltage of an input transistor in the mixer to which the radio-frequency signal is inputted to a center value of a dynamic range.
    Type: Grant
    Filed: September 23, 2009
    Date of Patent: March 27, 2012
    Assignee: Sony Corporation
    Inventor: Toshikazu Yoshida
  • Patent number: 8086209
    Abstract: A mixer such as an I/Q mixer, having an amplifier having first and second inputs and an output. The first input corresponding to, for example, an I input, and the second input corresponding to, for example, a Q input. The mixer also including a multiple way (M-way) switch having a single input in communication with the output of the amplifier; a frequency control input; and at least four outputs. The frequency control input is configured to receive a periodic signal, and the M-way switch is configured to switch a signal received on the single input to each of the at least four outputs at a switching frequency that is determined by the periodic signal. The M-way switch is operable to switch the input signal received on the single input to each of the at least four outputs in a serial fashion.
    Type: Grant
    Filed: October 29, 2007
    Date of Patent: December 27, 2011
    Assignee: Broadcom Corporation
    Inventor: Eric Rodal
  • Patent number: 8050649
    Abstract: A downconversion mixer with IM2 cancellation includes a mixer, an IM2 generator, and a scaling unit. The mixer frequency downconverts an input RF signal with an LO signal and generates an output baseband signal. The IM2 generator includes first and second field effect transistors (FETs) that receive the input RF signal and generate an intermediate signal having IM2 distortion. The scaling unit scales the intermediate signal to generate a scaled signal and further combines the scaled signal with the output baseband signal to cancel IM2 distortion in the output baseband signal. The IM2 generator may further include first and second amplifiers coupled between the source and gate of the first and second FETs, respectively. Different amounts of IM2 distortion and different temperature variation patterns may be generated in the intermediate signal by using different gains for the amplifiers.
    Type: Grant
    Filed: August 30, 2005
    Date of Patent: November 1, 2011
    Assignee: QUALCOMM Incorporated
    Inventors: Minghui Chen, Yue Wu
  • Patent number: 8019311
    Abstract: Methods and systems for recovering a DC component in a zero-IF radio receiver are disclosed that involve receiving a frequency modulated radio frequency broadcast signal, down-converting the frequency modulated radio frequency broadcast signal directly to an original baseband frequency signal, wherein the original baseband frequency signal includes an original DC component, filtering the original baseband signal to obtain a filtered baseband signal, wherein the original DC component is removed, analyzing modulus values of the filtered baseband signal to determine an estimated quantity for the original DC component, and adding the estimated quantity for the original DC component to the filtered baseband signal to compensate for removal of the original DC component such that a reconstructed baseband signal is obtained.
    Type: Grant
    Filed: June 27, 2008
    Date of Patent: September 13, 2011
    Assignee: iBiquity Digital Corporation
    Inventors: Michael Nekhamkin, Liangkai Yu
  • Patent number: 7904037
    Abstract: An exemplary embodiment of the present invention described and shown in the specification and drawings is a transceiver with a receiver, a transmitter, a local oscillator (LO) generator, a controller, and a self-testing unit. All of these components can be packaged for integration into a single IC including components such as filters and inductors. The controller for adaptive programming and calibration of the receiver, transmitter and LO generator. The self-testing unit generates is used to determine the gain, frequency characteristics, selectivity, noise floor, and distortion behavior of the receiver, transmitter and LO generator. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.
    Type: Grant
    Filed: November 18, 2008
    Date of Patent: March 8, 2011
    Assignee: Broadcom Corporation
    Inventors: Ahmadreza Rofougaran, Maryam Rofougaran, Jacob Rael, Syed Masood, Brima Ibrahim, Hung-Ming Chien, Stephen Wu, Meng-An Pan
  • Patent number: 7885624
    Abstract: A communication system with variable filter bandwidth includes a first mixer circuit configured to receive a communication signal and shift the frequency range of the communication signal to a first frequency range. A second mixer circuit is configured to receive the same communication signal and shift the frequency range of the communication signal to a second frequency range. An activation circuit is coupled to the first and second mixer circuits so as to provide an activation signal that activates at least one of the mixer circuits. A plurality of filter circuits are provided such that each filter circuit is configured to receive a signal from a corresponding mixer circuit, when the corresponding mixer circuit is activated.
    Type: Grant
    Filed: June 1, 2009
    Date of Patent: February 8, 2011
    Assignee: Agere Systems Inc.
    Inventor: Erik Busking
  • Patent number: 7813451
    Abstract: Systems, methods and apparatus for improving the coverage of a wireless network based on frequency shifting scheme. A wireless signal in a frequency band is shifted to another distinct band, and carried in the shifted band, using wired or wireless mediums to another location, wherein the wireless signal is shifted back to the original frequency band. The frequency shifting may make use of a conventional frequency shifting schemes such as mixer/filter and heterodyne. In one embodiment the wireless signal is frequency shifted by converting it to other representing signals (such as I/Q components) and forming the frequency-shifted signal from the representations. The system is may be used to increase in-door or outdoor coverage, as well as bridging between in-door and outdoor networks. The medium may use dedicated wiring or existing service wiring in a residence or building, including LAN, telephone, AC power and CATV wiring.
    Type: Grant
    Filed: January 11, 2006
    Date of Patent: October 12, 2010
    Assignee: MobileAccess Networks Ltd.
    Inventors: Yehuda Binder, Ami Hazani
  • Patent number: 7791478
    Abstract: In some embodiments of a radio frequency identification (RFID) system, multiple bits of data may be encoded at the same time based on a frequency shift key (FSK) modulation technique using multiple frequencies, by permitting any or all of the frequencies to be modulated on a carrier wave at the same time. In some embodiments a parallel but asymmetric down-conversion of the frequencies may allow both frequencies to be detected with identical filters.
    Type: Grant
    Filed: December 1, 2005
    Date of Patent: September 7, 2010
    Assignee: Intel Corporation
    Inventor: Joshua Posamentier
  • Publication number: 20100210229
    Abstract: An broadcasting receiver suitable for receiving a broadcasting signal transmitted in an IBOC signal format, includes: a narrowband filtering means suitable for processing an analog broadcasting signal included in the broadcasting signal; a wideband filtering means suitable for processing a digital broadcasting signal included in the broadcasting signal; a demodulating means for demodulating the broadcasting signal; a signal level detecting means for detecting a level of the broadcasting signal; a digital determining means for determining whether the broadcasting signal includes digital broadcasting signal or not; and a filter switching means for switching filtering means for use in processing the broadcasting signal to be input to the demodulating means between the narrowband filtering means and the wideband filtering means, according to the level of the detected broadcasting signal, when the digital determining means determines that the broadcasting signal does not include the digital broadcasting signal.
    Type: Application
    Filed: August 30, 2007
    Publication date: August 19, 2010
    Inventors: Kazuyoshi Inako, Kazuo Koyama, Masanori Ishida, Naoki Nakajima
  • Patent number: 7702305
    Abstract: An instrumentation receiver architecture for processing an RF signal has a dual-IF channel architecture, a low-band IF channel and a high-band IF channel, and a tunable oscillator, such as a yttrium-iron-garnet (YIG) tunable oscillator (YTO), a voltage controlled oscillator (VCO), a bank of VCOs and the like, providing a different mixing frequency range to each channel, generally a higher frequency range to the high-band IF channel than to the low-band IF channel. At the input to the high-band IF channel is a bank of preselection filters for selecting a frequency band from the RF signal for processing by the high-band IF channel. A switch selects the output from one of the low-band and high-band IF channels for further processing.
    Type: Grant
    Filed: February 13, 2007
    Date of Patent: April 20, 2010
    Assignee: Tektronix, Inc.
    Inventor: Jeffrey D. Earls
  • Patent number: 7664475
    Abstract: A multi-band wireless transceiver having a plurality of signal-processing paths, and further having a function of making wireless communication through a plurality of frequency bands by selecting one of the signal-processing paths, includes a band identification circuit for identifying a frequency band, the band identification circuit identifying a frequency band in dependence on a frequency-band information received from a controller which controls an operation of the multi-band wireless transceiver, and selecting one of the signal-processing paths in accordance with the identified frequency band.
    Type: Grant
    Filed: September 6, 2005
    Date of Patent: February 16, 2010
    Assignee: NEC Corporation
    Inventor: Masaki Ichihara
  • Patent number: 7653145
    Abstract: Frequency translation and applications of the same are described herein, including RF modem and wireless local area network (WLAN) applications. In embodiments, the WLAN invention includes an antenna, an LNA/PA module, a receiver, a transmitter, a control signal generator, a demodulation/modulation facilitation module, and a MAC interface. The WLAN receiver includes at least one universal frequency translation module that frequency down-converts a received EM signal. In embodiments, the UFT based receiver is configured in a multi-phase embodiment to reduce or eliminate re-radiation that is caused by DC offset. The WLAN transmitter includes at least one universal frequency translation module that frequency up-converts a baseband signal in preparation for transmission over the wireless LAN. In embodiments, the UFT based transmitter is configured in a differential and multi-phase embodiment to reduce carrier insertion and spectral growth.
    Type: Grant
    Filed: January 25, 2005
    Date of Patent: January 26, 2010
    Assignee: ParkerVision, Inc.
    Inventors: David F. Sorrells, Michael J. Bultman, Robert W. Cook, Richard C. Looke, Charley D. Moses, Jr., Gregory S. Rawlins, Michael W. Rawlins
  • Patent number: 7643808
    Abstract: A first and a second signal (base band and local oscillator), respectively modulated to a first and a second frequency, are mixed to deliver an output signal at a frequency obtained by combining the first and second frequencies. The mixing is accomplished through a variable resistance stage controlled by the second signal and connected between a first and a second potential to deliver the mixed output signal. A control stage is configured to drive the resistance variation of the variable resistance stage according to the first signal.
    Type: Grant
    Filed: July 5, 2006
    Date of Patent: January 5, 2010
    Assignee: STMicroelectronics S.A.
    Inventor: Vincent Knopik
  • Patent number: 7606542
    Abstract: A disclosed method tunes a signal from a channelized spectrum having a predetermined channel spacing. A signal of interest having a predetermined maximum bandwidth is mixed with a local oscillator signal, which has a frequency that is an integer multiple of the channel spacing or one-half of a channel spacing displaced from an integer multiple of the channel spacing. The local oscillator signal is selected to frequency translate the signal of interest to within a near-baseband passband whose lower edge is spaced from DC by at least about the maximum bandwidth of the signal of interest. Problems associated with 1/f noise, DC offsets, and self-mixing products are avoided or substantially diminished. Other methods and systems are also disclosed.
    Type: Grant
    Filed: June 15, 2005
    Date of Patent: October 20, 2009
    Assignee: University of Washington
    Inventor: Edwin A. Suominen
  • Patent number: 7587224
    Abstract: The method and apparatus of the present invention provide for a configurable radio front end topology that allows selectable operation in a single balanced mode and in a double balanced mode of operation. Logic associated with a baseband processor determines whether to operate in a single or double balanced mode of operation and produces the mode control signal to control selective coupling of circuit components according to the specified mode. Switching circuitry is used to switch a Balun in and out of connectivity. Further, a pair of LO polarity blocks are operable to determine the polarity of a differential LO received by associated mixers according to whether a single balanced or double balanced mode is in use.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: September 8, 2009
    Assignee: Broadcom Corporation
    Inventor: Alireza Zolfaghari
  • Patent number: 7558548
    Abstract: A method and apparatus to receive and down convert high frequency radio signals to low frequency or base band frequency is disclosed. A mixer used with a sampler produces a multi mode/multi band software enhanced radio receiver capable of supporting multiple air interfaces. The local oscillator of the disclosed mixer is harmonically related to the sampler frequency. A signal is first down converted by the mixer to a lower frequency or intermediate frequency, the signal is then sub sampled by the sub sampler, the signal is then converted to discrete time and all further processes are discrete. Successive decimation, filtering and demodulation in discrete or continuous time achieve selectivity and down conversion to base band.
    Type: Grant
    Filed: November 2, 2005
    Date of Patent: July 7, 2009
    Inventor: Alon Konchistky
  • Patent number: 7548726
    Abstract: An exemplary embodiment of the present invention described and shown in the specification and drawings is a transceiver with a receiver, a transmitter, a local oscillator (LO) generator, a controller, and a self-testing unit. All of these components can be packaged for integration into a single IC including components such as filters and inductors. The controller for adaptive programming and calibration of the receiver, transmitter and LO generator. The self-testing unit generates is used to determine the gain, frequency characteristics, selectivity, noise floor, and distortion behavior of the receiver, transmitter and LO generator. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.
    Type: Grant
    Filed: October 27, 2000
    Date of Patent: June 16, 2009
    Assignee: Broadcom Corporation
    Inventor: Ahmadreza Rofougaran
  • Patent number: 7535976
    Abstract: A receiver to process a RF input signal having a plurality of channels includes a direct down conversion circuit, a demodulation circuit, and a local oscillator circuit. The direct down conversion circuit provides a downconverted signal based on the RF input signal and a local oscillator signal. The demodulation circuit receives the downconverted signal and provides a demodulated signal. The local oscillator circuit sets a frequency of the local oscillator signal based on a selected channel of the plurality of channels.
    Type: Grant
    Filed: July 30, 2004
    Date of Patent: May 19, 2009
    Assignee: Broadcom Corporation
    Inventors: Steven Jaffee, Donald McMullin, Ramon Gomez