Fm Final Modulation Patents (Class 381/3)
  • Patent number: 11127405
    Abstract: Systems, methods, and computer-readable media are disclosed for systems and methods for selective requests for authentication for voice-based launching of applications. Example methods may include receiving first audio data representing an utterance, determining that the device is in a first operating mode when the audio data was received, determining that the device is in a locked state when the audio data is received, and receiving, from a remote system, a command to display information based at least on part on the audio data. Certain methods may include receiving an indication that the utterance was spoken by a user authorized to access the information while in the first operating mode and the locked state, and causing presentation of the information by the device.
    Type: Grant
    Filed: March 14, 2018
    Date of Patent: September 21, 2021
    Assignee: Amazon Technologies, Inc.
    Inventors: Kynan Dylan Antos, Jenny Toi Wah Lam, Mark Yoshitake, Ankur Narendra Bhai Vachhani, Blade Imsande McRae, Robert Williams, James Martin Conway, Nedim Fresko, Michael Wendling, Mustafa Husain
  • Patent number: 10616028
    Abstract: An apparatus is configured to, based on a first signal comprising one or more data transmission frames received from a first radio device by a second radio device. The first signal has a particular carrier frequency of a carrier wave thereof and the one or more data transmission frames comprising a plurality of symbols provided at a particular symbol frequency. The carrier frequency and symbol frequency based on a reference clock frequency of the first radio device. One or more of an estimate of the particular carrier frequency is determined and an estimate of the particular symbol frequency relative to a reference clock frequency of the second radio device and provide for transmission of a response signal from the second radio device to the first radio device.
    Type: Grant
    Filed: January 15, 2018
    Date of Patent: April 7, 2020
    Assignee: NXP B.V.
    Inventors: Marinus van Splunter, Arie Geert Cornelis Koppelaar, Frank Leong
  • Patent number: 9837061
    Abstract: Embodiments of systems and methods for blending multi-channel signals are described. In one embodiment, a method for blending multi-channel signals involves computing component signals from the multi-channel signals, cross-fading the component signals based on different temporal rates to generate cross-faded component signals and generating a blended multi-channel signal based on the cross-faded component signals. Other embodiments are also described.
    Type: Grant
    Filed: June 23, 2014
    Date of Patent: December 5, 2017
    Assignee: NXP B.V.
    Inventor: Temujin Gautama
  • Patent number: 9356638
    Abstract: An FM audio receiver can include a mono/stereo detector that causes the audio receiver to output either a monophonic or a stereophonic signal based on a received pilot tone energy. An accurate operation of the receiver, including but not limited to correct decoding of monophonic/stereophonic reception, can be based on the receiver operating with the same rated maximum system deviation (RMSD) as the received signal itself. Aspects of the disclosure describe a system and method of detecting and matching a receiver's RMSD to that of a received signal by demodulating a carrier bearing a an input signal over a first bandwidth, extracting a pilot energy signal from the input signal, and demodulating the carrier bearing the input signal over a second bandwidth if the pilot energy signal is within a pilot energy range for a first predetermined amount of time.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: May 31, 2016
    Assignee: Marvell International Ltd.
    Inventor: Chris Cheng-Chieh Lee
  • Patent number: 9258641
    Abstract: Audio capture based on logarithmic conversion. At least some of the illustrative embodiments are methods including capturing audio represented by an electrical signal, the electrical signal having both positive voltage portions and negative voltage portions. In some cases, the capture is by: performing logarithmic analog-to-digital conversion on the positive voltage portions to create a first plurality of digital values; and performing logarithmic analog-to-digital conversion on the negative voltage portions to create a second plurality of digital values; and storing representations of the first and second plurality of digital values to a storage medium.
    Type: Grant
    Filed: September 24, 2012
    Date of Patent: February 9, 2016
    Assignee: QBIZ, LLC
    Inventor: John R. Tuttle
  • Patent number: 9154171
    Abstract: A reconfigurable radio frequency circuit is arranged for receiving at least one carrier in a wireless communications terminal arranged to receive at least two carriers, each of the two carriers being transmitted in a different one of a plurality of operating frequency bands, and each of the plurality of operating frequency bands occupying a part of a first or a second frequency range. The circuit includes a combiner for connecting the output of a first receiver filter at a first operating frequency band within the first frequency range to the input of an amplifier and for connecting the output of a second receiver filter at a second operating frequency band within the second frequency range to the input of the amplifier. The amplifier has a selectable operating frequency range, the operating frequency range being selectable at least between the first frequency range and the second frequency range.
    Type: Grant
    Filed: March 1, 2013
    Date of Patent: October 6, 2015
    Assignee: BROADCOM CORPORATION
    Inventors: Seppo Rousu, Juha Valtanen
  • Patent number: 9025773
    Abstract: The approach shown provides for an efficient implementation of time response, level response and frequency response alignment between two audio sources such as DAB and FM that may be time offset from each other by as much as 2 seconds, and produces an aurally undetectable transition between the sources. Computational load is significantly reduced over the approaches known in the prior art.
    Type: Grant
    Filed: April 21, 2012
    Date of Patent: May 5, 2015
    Assignee: Texas Instruments Incorporated
    Inventors: John Elliott Whitecar, Trudy D. Stetzler
  • Publication number: 20150078554
    Abstract: A personal listening system uses the FM broadcast band for transmission and reception. The system includes a base unit and physically separate right- and left-ear listening units. The base unit includes an FM stereo transmitter. Each listening unit demodulates and amplifies the received signal, but the right-ear unit only amplifies the right channel and the left-ear unit only amplifies the left channel. The base unit may be a digital music player, book reader, video player, smart cellular telephone, or any other portable device. The base unit may include a display for displaying the selected FM frequency. The base unit may be a self-contained or integrated unit, or a device that couples to a digital music player, smart cellular telephone or other device to receive the audio signal therefrom. The right- and left-ear listening units may be any type of on-ear, in-ear or around-ear sound delivery devices including earbuds.
    Type: Application
    Filed: October 14, 2014
    Publication date: March 19, 2015
    Inventor: John G. Posa
  • Publication number: 20150063571
    Abstract: The present invention relates to a system that integrates various transmission/reception technologies, e.g. satellite, frequency modulated (FM), etc. for specific highway use, allowing the use of one and the same frequency-modulated frequency along a road in a synchronized manner.
    Type: Application
    Filed: March 25, 2013
    Publication date: March 5, 2015
    Inventor: Carlos Antonio Coelho
  • Publication number: 20140355764
    Abstract: Systems and methods are disclosed that may be implemented to process a received RF spectrum that includes both analog modulated and digitally modulated RF signals to blend between a digital demodulated signal and an analog demodulated signal obtained from the received RF spectrum prior to performing one or more signal quality mitigation operations on the blended signal (e.g., such as stereo blend, hi-cut, etc.). In one embodiment, the digital demodulated signal and the analog demodulated signal may include at least some of the same information, e.g., such as information from simulcast digital and analog channels that are obtained from the same received RF spectrum.
    Type: Application
    Filed: May 31, 2013
    Publication date: December 4, 2014
    Inventor: Javier Elenes
  • Patent number: 8867748
    Abstract: A personal listening system uses the FM broadcast band for transmission and reception. The system includes a base unit and physically separate right- and left-ear listening units. The base unit includes an FM stereo transmitter. Each listening unit demodulates and amplifies the received signal, but the right-ear unit only amplifies the right channel and the left-ear unit only amplifies the left channel. The base unit may be a digital music player, book reader, video player, smart cellular telephone, or any other portable device. The base unit may include a display for displaying the selected FM frequency. The base unit may be a self-contained or integrated unit, or a device that couples to a digital music player, smart cellular telephone or other device to receive the audio signal therefrom. The right- and left-ear listening units may be any type of on-ear, in-ear or around-ear sound delivery devices including earbuds.
    Type: Grant
    Filed: December 19, 2011
    Date of Patent: October 21, 2014
    Inventor: John G. Posa
  • Publication number: 20140226822
    Abstract: The present document relates to audio signal processing, in particular to an apparatus and a corresponding method for improving an audio signal of an FM stereo radio receiver. In particular, the present document relates to a method and system for reliably detecting the quality of a received FM stereo radio signal and for selecting an appropriate processing based on the detected quality. An apparatus (20) configured to estimate the quality of a received multi-channel FM radio signal is described. The received multi-channel FM radio signal is representable as a mid signal and a side signal, and the side signal is indicative of a difference between a left signal and a right signal.
    Type: Application
    Filed: October 1, 2012
    Publication date: August 14, 2014
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Jonas Engdegard, Heiko Purnhagen, Leif Sehlstrom
  • Patent number: 8774416
    Abstract: The invention refers to a method for a receiver (1) having a signal path (3) incorporating a tuner (4), a frequency demodulator circuit (5) for supplying an analog stereo multiplex signal comprising a baseband stereo sum signal, a 19 kHz stereo pilot and a stereo difference signal, which is double sideband amplitude-modulated on a suppressed 38 kHz subcarrier, a sampler (6) for converting the analog stereo multiplex signal into a time discrete digital stereo multiplex signal and a stereo decoder (7) for decoding the time discrete digital stereo multiplex signal into a time-discrete digital stereo sum and a time discrete digital stereo difference signal. According to the invention the analog stereo multiplex signal is converted into a time discrete digital stereo multiplex signal and then the time discrete digital stereo multiplex signal is shifted over a frequency of 19 kHz to extract the pilot tone.
    Type: Grant
    Filed: October 27, 2003
    Date of Patent: July 8, 2014
    Assignee: NXP, B.V.
    Inventor: Rafael Jan Jozef Meeusen
  • Patent number: 8688045
    Abstract: Exemplary embodiments include a frequency modulation (FM) transmitter and a non-FM receiver, which may be implemented on the same IC chip. The FM transmitter may include a digital FM modulator, a lowpass filter, an amplifier, and an LC tank circuit. The digital FM modulator may receive a digital input signal, perform FM modulation with the digital input signal, and provide a digital FM signal. The lowpass filter may filter the digital FM signal and provide a filtered FM signal. The amplifier may amplify the filtered FM signal and provide an output FM signal. The LC tank circuit may filter the output FM signal. The digital FM modulator may perform FM modulation by changing a variable divider ratio of a multi-modulus divider within a PLL. A delta-sigma modulator may receive the digital input signal and generate a modulator output signal used to obtain the variable divider ratio.
    Type: Grant
    Filed: November 19, 2008
    Date of Patent: April 1, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: I-Hsiang Lin, Tzu-wang Pan, Yi Zeng
  • Publication number: 20140072122
    Abstract: The invention provides an audio signal processing system in which a magnitude spectrum of a frequency domain audio signal is processed based on a measure of multipath interference. The processing keeps the magnitude spectrum approximately fixed during periods of multipath interference, for example by replacing it with a temporally smoothed version of the magnitude spectrum. The magnitude spectrum (processed if required) and the phase spectrum are combined to derive a frequency domain output, which is transformed to the time domain.
    Type: Application
    Filed: September 10, 2013
    Publication date: March 13, 2014
    Applicant: NXP B.V .
    Inventor: Temujin Gautama
  • Patent number: 8619997
    Abstract: A receiving apparatus includes: a local oscillator to output first- and second-local-oscillator signals whose phases are orthogonal to each other; a mixer to output first- and second-intermediate-frequency signals; a first filter to allow a component from a desired signal to pass therethrough, and eliminate a component from an image signal having a frequency symmetrical with that of the desired signal, in the first- and second-intermediate-frequency signals; a second filter to allow a component from the image signal to pass therethrough, and eliminate a component from the desired signal, in the first- and second-intermediate-frequency signals; a comparator to compare levels between output signals of the first and second filters; and a control unit to switch a frequency of the first- and second-local-oscillator signals to a difference frequency between a frequency of the desired signal and the intermediate frequency or a sum frequency thereof, according to a comparison result of the comparator.
    Type: Grant
    Filed: December 17, 2010
    Date of Patent: December 31, 2013
    Assignees: Sanyo Semiconductor Co., Ltd., Semiconductor Components Industries, LLC
    Inventors: Kazunari Kurokawa, Satoru Sekiguchi
  • Patent number: 8615092
    Abstract: A sound processing device includes: a plurality of sound input units; a detecting unit for detecting a frequency component of each sound input to the plurality of sound signal unit, the each sound arriving from a direction approximately perpendicular to a line determined by arrangement positions of two sound input units among the plurality of sound input units; a correction coefficient unit for obtaining a correction coefficient for correcting a level of at least one of the sound signals generated from the input sounds by the two sound input units so as to match the levels of the sound signals with each other based on the sound of the detected frequency component; a correcting unit for correcting the level of at least one of the sound signals using the obtained correction coefficient; and a processing unit for performing a sound process based on the sound signal with the corrected level.
    Type: Grant
    Filed: May 26, 2010
    Date of Patent: December 24, 2013
    Assignee: Fujitsu Limited
    Inventor: Naoshi Matsuo
  • Patent number: 8571576
    Abstract: A processor for a user-portable device, the user-portable device comprising FM transmission circuitry, wherein the processor is configured to obtain a first set of valid geo-specific FM transmission parameters for the current geographical location of the user-portable device based on received global positioning satellite (GPS) data for the current geographical location of the user-portable device; and provide signalling to configure the FM transmission circuitry to use the valid first set of geo-specific FM transmission parameters.
    Type: Grant
    Filed: November 16, 2009
    Date of Patent: October 29, 2013
    Assignee: Nokia Corporation
    Inventors: Seemal Brandt, Ralf Brandt
  • Publication number: 20130279700
    Abstract: The approach shown provides for an efficient implementation of time response, level response and frequency response alignment between two audio sources such as DAB and FM that may be time offset from each other by as much as 2 seconds, and produces an aurally undetectable transition between the sources. Computational load is significantly reduced over the approaches known in the prior art.
    Type: Application
    Filed: April 21, 2012
    Publication date: October 24, 2013
    Applicant: Texas Instruments Incorporated
    Inventors: John Elliott Whitecar, Trudy D Stetzler
  • Patent number: 8526622
    Abstract: Television audio signal encoders include a matrix that sums a left channel audio signal and a right channel audio signal to produce a sum signal. The matrix also subtracts one of the left and right audio signals from the other to produce a difference signal. The encoders also include a configurable infinite impulse response digital filter that selectively uses one or more sets of filter coefficients to filter the difference signal and/or the sum signals. Each selectable set of filter coefficients is associated with a unique filtering application to prepare the difference signal for transmission. Decoders with the matrix are also disclosed.
    Type: Grant
    Filed: September 7, 2010
    Date of Patent: September 3, 2013
    Assignee: THAT Corporation
    Inventors: Matthew S. Barnhill, Roger R. Darr
  • Publication number: 20130182851
    Abstract: A processing unit for processing a multi-channel audio signal has a delay element (40) for delaying an FM sum signal (sum) and a converter arrangement (T) for converting an FM difference signal (duff) and a noise signal (diffnoise) to the frequency domain. Frequency-based noise suppression is used to derive a de-noised frequency-domain difference signal using a gain function which is limited to a maximal and a minimal value. This is then converted to the time domain, and the first and second audio signals are calculated from a delayed sum signal (sum2) and the de-noised time domain difference signal (diff2).
    Type: Application
    Filed: January 8, 2013
    Publication date: July 18, 2013
    Applicant: NXP B.V.
    Inventor: NXP B.V.
  • Patent number: 8406717
    Abstract: Systems and techniques for digital processing of FM stereo signals are described. In some implementations, a receiver system is provided. The receiver system can include a received signal input configured to receive a digital signal based on a received mono signal or a received stereo signal. The receiver system can also include a stereo detector coupled with the received signal input, the stereo detector configured to produce a stereo detection signal indicating either a received stereo signal or a received mono signal. The receiver system can further include a digital signal processor coupled with the stereo detector, the digital signal processor configured to process the digital signal based on stereo transmission when the stereo detection signal indicates a received stereo signal and process the digital signal based on mono transmission when the stereo detection signal indicates a received mono signal.
    Type: Grant
    Filed: July 9, 2008
    Date of Patent: March 26, 2013
    Assignee: Marvell International Ltd.
    Inventor: Hui-Ling Lou
  • Publication number: 20120230495
    Abstract: An electronic circuit (100) for use in a wireless receiver (1720). The circuit (100) includes an audio demodulator (15), an audio envelope portion (35) operable to deliver an audio envelope signal, a high pass filter (38) coupled between the audio demodulator (15) and the audio envelope portion (35), a volume control (25) fed by the audio demodulator (15) and operable to provide a controllable audio signal output, and a controller (45) responsive to the audio envelope portion (35) to provide an attenuation control to the volume control (25). Other circuits, receivers, processes of operation, processes of manufacture, and processes of testing are disclosed.
    Type: Application
    Filed: June 29, 2011
    Publication date: September 13, 2012
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Sriram Murali, Aravind Ganesan
  • Publication number: 20120207307
    Abstract: The invention relates to an apparatus for improving a stereo audio signal of an FM stereo radio receiver. The apparatus comprises a parametric stereo (PS) parameter estimation stage. The parameter estimation stage is configured to determine one or more parametric stereo parameters based on the stereo audio signal in a frequency-variant or frequency-invariant manner. Preferably, these PS parameters are time- and frequency-variant. Moreover, the apparatus comprises an upmix stage. The upmix stage is configured to generate the improved stereo signal based on a first audio signal and the one or more parametric stereo parameters. The first audio signal is obtained from the stereo audio signal, e.g. by a downmix operation in a downmix stage. The PS parameter estimation stage may be part of a PS encoder. The upmix stage may be part of a PS decoder.
    Type: Application
    Filed: September 7, 2010
    Publication date: August 16, 2012
    Inventors: Jonas Engdegard, Heiko Purnhagen, Karl Jonas Roeden
  • Publication number: 20120201387
    Abstract: An FM radio receiving apparatus includes a stereo decoder unit 301 for separating a stereo signal of a received FM stereo broadcasting wave into voice signals of individual channels, a binarization processing unit 302 for binarizing the individual voice signals of the channels separated by the stereo decoder unit, and a correlation deciding unit 303 for storing the voice signals of the individual channels binarized by the binarization processing unit 302 for a prescribed time period, and for deciding correlation from the voice signals of the individual channels stored, and the FM radio receiving apparatus controls the degree of separation of the individual channels of the stereo signal in accordance with the correlation decided by the correlation deciding unit 303.
    Type: Application
    Filed: February 15, 2010
    Publication date: August 9, 2012
    Inventors: Yuji Matsuda, Tatsuya Obata
  • Publication number: 20120155649
    Abstract: A personal listening system uses the FM broadcast band for transmission and reception. The system includes a base unit and physically separate right- and left-ear listening units. The base unit includes an FM stereo transmitter. Each listening unit demodulates and amplifies the received signal, but the right-ear unit only amplifies the right channel and the left-ear unit only amplifies the left channel. The base unit may be a digital music player, book reader, video player, smart cellular telephone, or any other portable device. The base unit may include a display for displaying the selected FM frequency. The base unit may be a self-contained or integrated unit, or a device that couples to a digital music player, smart cellular telephone or other device to receive the audio signal therefrom. The right- and left-ear listening units may be any type of on-ear, in-ear or around-ear sound delivery devices including earbuds.
    Type: Application
    Filed: December 19, 2011
    Publication date: June 21, 2012
    Inventor: John G. Posa
  • Patent number: 8050412
    Abstract: A demodulator (10) converts television signals to video baseband signals and audio baseband signals including stereo signals representing a right channel signal value and a left channel signal value. A DSP (60) recursively finds a preferred coefficient value for a scaling that reduces stereo separation due to amplitude variation of the right and left channel signal values. The preferred coefficient value is thereafter used for scaling the right and left channel signal values.
    Type: Grant
    Filed: December 14, 2004
    Date of Patent: November 1, 2011
    Assignee: Broadcom Corporation
    Inventor: David Chaohua Wu
  • Patent number: 8045717
    Abstract: A stereo decoder and a method therefor are provided. The stereo decoder receives a MPX signal from an FM demodulator, and comprises a first auto-calibration circuit, a band-pass filter, a second auto-calibration circuit, a slicer and a PLL circuit. The first auto-calibration circuit generates a first control signal. The band-pass filter generates the pilot signal by filtering the MPX signal with a center frequency set by the first control signal. The second auto-calibration circuit generates a second control signal. The slicer converts the pilot signal into a square wave signal. The PLL circuit comprises a voltage controlled oscillator for generating an oscillation frequency in response to the second control signal. The PLL circuit receives the square wave signal to generate the reference signal around the predetermined frequency in response to the oscillation frequency.
    Type: Grant
    Filed: April 13, 2006
    Date of Patent: October 25, 2011
    Assignee: Media Tek Inc.
    Inventors: Chieh Hung Chen, Hsiang-Hui Chang, Chih-Chien Huang
  • Publication number: 20110243333
    Abstract: The disclosed BTSC encoder includes a left high pass filter means for receiving a digital left channel audio signal and for digitally high pass filtering the digital left channel audio signal and thereby generating a digital left filtered signal; a right high pass filter means for receiving a digital right channel audio signal and for digitally high pass filtering the digital right channel audio signal and thereby generating a digital right filtered signal; a matrix means for receiving the digital left and digital right filtered signals, and including means for summing the digital left and digital right filtered signals and thereby generating a digital sum signal, and including means for subtracting one of the digital left and digital right filtered signals from the other of the digital left and digital right filtered signals and thereby generating a digital difference signal; a difference channel processing means for digitally processing the digital difference signal; and a sum channel processing means for d
    Type: Application
    Filed: June 29, 2011
    Publication date: October 6, 2011
    Applicant: THAT CORPORATION
    Inventor: Christopher M. Hanna
  • Patent number: 8009835
    Abstract: A front-end processing circuit applies predetermined processing to an input signal and outputs a processed signal. A frequency modulation circuit applies frequency modulation to the output signal of the front-end processing circuit and outputs a processed signal. The front-end processing circuit includes a variable amplifier and a level detector. The variable amplifier receives a feedback signal and amplifies a signal by an amplification factor corresponding to the feedback signal. The level detector outputs the feedback signal to the variable amplifier in accordance with a level of a signal obtainable in a circuit succeeding the variable amplifier. The front-end processing circuit maintains the signal supplied to the frequency modulation circuit at a constant level.
    Type: Grant
    Filed: September 28, 2006
    Date of Patent: August 30, 2011
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Masaki Kinoshita, Nobuo Takahashi, Satoshi Terada
  • Publication number: 20110194699
    Abstract: Aspects of a method and system for enhanced sound quality for stereo audio are provided. In this regard, levels of audio signals received via an FM radio channel may be controlled based on a signal-to-noise ratio (SNR) of the RF channel. The SNR of the FM radio channel may be determined based on signal strength in an unused portion of the FM radio channel. The recovered audio signals may comprise an FM multiplex signal, and an unused portion of the FM radio channel may be a guard band adjacent to a carrier of the FM multiplex signal. A level of one or both of a mono component and a stereo component of an FM multiplex signal may be controlled based on the SNR.
    Type: Application
    Filed: February 5, 2010
    Publication date: August 11, 2011
    Inventors: Thomas Baker, Brima Ibrahim, Hea Joung Kim
  • Publication number: 20110170698
    Abstract: An input signal is input via a first resistor to an inverting input terminal of an operational amplifier. A second resistor is provided on a feedback path between an output terminal and the inverting input terminal of the operational amplifier. A control voltage Vcnt output from the operational amplifier is input to a VCO. A frequency divider frequency-divides an output signal Sout of the VCO. A phase comparator compares an output signal from the frequency divider with a reference clock signal and outputs a voltage according to a phase difference. A loop filter removes a high-frequency component of an output voltage Vcp of the phase comparator and outputs the voltage to a non-inverting input terminal of the operational amplifier.
    Type: Application
    Filed: March 28, 2011
    Publication date: July 14, 2011
    Applicant: ROHM CO., LTD.
    Inventors: Hirofumi KOMORI, Takeshi SAGARA
  • Patent number: 7961890
    Abstract: A parametric representation of a multi-channel audio signal describes the spatial properties of the audio signal well with compact side information when a coherence information, describing the coherence between a first and a second channel, is derived within a hierarchical encoding process only for channel pairs including a first channel having only information of a left side with respect to a listening position and including a second channel having only information from a right side with respect to a listening position. As within the hierarchical process the multiple audio channels of the audio signal are downmixed iteratively into monophonic channels, one can pick the relevant parameters from an encoding step involving only channel pairs carrying the information needed to describe the spatial properties of the multi-channel audio signal.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: June 14, 2011
    Assignees: Fraunhofer-Gesellschaft zur Foerderung der Angewandten Forschung, e.V., Coding Technologies AB, Koninklijke Philips Electronics N.V.
    Inventors: Andreas Hölzer, Jürgen Herre, Heiko Purnhagen, Kristofer Kjörling, Jonas Röden, Lars Villemoes, Jonas Engdegard, Jeroen Breebaart, Erik Schuijers, Werner Oomen
  • Patent number: 7936228
    Abstract: An input signal is input via a first resistor to an inverting input terminal of an operational amplifier. A second resistor is provided on a feedback path between an output terminal and the inverting input terminal of the operational amplifier. A control voltage Vcnt output from the operational amplifier is input to a VCO. A frequency divider frequency-divides an output signal Sout of the VCO. A phase comparator compares an output signal from the frequency divider with a reference clock signal and outputs a voltage according to a phase difference. A loop filter removes a high-frequency component of an output voltage Vcp of the phase comparator and outputs the voltage to a non-inverting input terminal of the operational amplifier.
    Type: Grant
    Filed: December 5, 2006
    Date of Patent: May 3, 2011
    Assignee: Rohm Co., Ltd.
    Inventors: Hirofumi Komori, Takeshi Sagara
  • Publication number: 20110043367
    Abstract: An intelligent notification appliance circuit has a controller and one or more addressable notification appliances coupled with a single pair of wires. The controller outputs integrated power, audio and control signals, and transmits the integrated signals to the one or more addressable notification appliances. Thus, the one or more addressable notification appliances are powered, operated, controlled, and monitored using the intelligent notification appliance circuit. When the intelligent notification appliance circuit is implemented in a fire and/or mass notification system, that system is able to provide integrated audio signals, power signals and control signals over a single pair of wires. The integrated audio signals may carry data indicative of live or recorded music and/or voice messages, such as: mass notification messages, general page, voice evacuation, and the like.
    Type: Application
    Filed: August 19, 2009
    Publication date: February 24, 2011
    Inventors: Donald Edward BECKER, Dennis Ted Rock, Morris Stoops, Jan A. Braam, William Edwards, Bruce Ray Montgomery, JR.
  • Patent number: 7822211
    Abstract: A stereo decoding system comprises an oscillator, a bandpass filter, a PLL unit and a stereo decoder. The oscillator generates a first signal with a center frequency. The bandpass filter receives a stereo multiplexed signal and the first signal to filter out a pilot signal. The PLL unit receives the pilot signal to generate a PLL output signal. The stereo decoder receives the stereo multiplexed signal and the PLL output signal to separate a left channel signal and a right channel signal from the stereo multiplexed signal.
    Type: Grant
    Filed: July 12, 2006
    Date of Patent: October 26, 2010
    Assignee: Mediatek Inc.
    Inventors: Hsiang-Hui Chang, Chih-Chien Huang, Chieh Hung Chen
  • Patent number: 7801311
    Abstract: A stereo decoder includes a first digital filter for producing a first filtered composite audio signal and a second digital filter for producing a second filtered composite audio signal. A sum/difference network produces a left channel signal and a right channel signal. A processor executes operational instructions that calculate a first corner frequency of a first digital filter based on a signal quality of the FM signal, calculate a first set of filter coefficients for the first digital filter based on the first corner frequency and an approximation of a filter transform, calculate a second corner frequency of a second digital filter based on the signal quality, and calculate a second set of filter coefficients for the second digital filter, based on the second corner frequency and the approximation of the filter transform.
    Type: Grant
    Filed: September 15, 2005
    Date of Patent: September 21, 2010
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Jon David Hendrix, Thomas Glen Ragan
  • Patent number: 7787630
    Abstract: A novel system and method for correcting the residual phase offset between a recovered pilot signal and the received stereo signal. The invention uses a Costas loop as an auxiliary loop in addition to the pilot recovery phase locked loop (PLL) to lock onto the stereo component itself. This auxiliary loop functions to generate a pilot to stereo component phase correction signal that is added to the stereo carrier phase The resultant phase is used to generate the recovered pilot carrier used to demodulate the stereo MPX signal. The Costas loop is activated together with the main pilot recovery PLL that locks onto the pilot tone in the demodulated MPX signal. The auxiliary Costas loop is operative to track and determine a residual phase error of up to several degrees.
    Type: Grant
    Filed: August 16, 2006
    Date of Patent: August 31, 2010
    Assignee: Texas Instruments Incorporated
    Inventors: Gregory Lerner, Nir Tal, Ofer Friedman
  • Publication number: 20100177902
    Abstract: An audio transmission system of an FM carrier frequency signal conveys an analog audio signal with minimum distortion, high signal to noise ratio, and minimum phase distortion. The system employs digital data processing blocks to generate a VHF FM carrier signal which is subsequently converted to an UHF FM carrier frequency signal for transmission wirelessly to a receiver for reproducing the audio signal.
    Type: Application
    Filed: January 15, 2009
    Publication date: July 15, 2010
    Inventors: Allen Kam Kwong Wong, Wai Ho Cheung
  • Patent number: 7693290
    Abstract: A sound reproduction device such as a radio receiver or a cellular phone includes an antenna, a control unit and a speaker. The control unit determines whether a radio wave receiving condition is satisfactory. The receiving condition is represented by field strength of the radio wave or a degradation of a sound signal in the radio wave. If the receiving condition is not satisfactory, the control unit adds an acoustic effect to the sound signal thereby to notify listeners of degradation of receiving condition. The acoustic effect may be a changing of sound image localization, a changing of a frequency characteristic and a changing of a reverberation characteristic. The acoustic effect is stopped for a specified period after the acoustic effect is added, even when the receiving condition is not satisfactory.
    Type: Grant
    Filed: July 26, 2005
    Date of Patent: April 6, 2010
    Assignee: DENSO CORPORATION
    Inventor: Tomoaki Mizuno
  • Patent number: 7667553
    Abstract: In a frequency modulator, a VCO oscillates at a frequency according to a voltage applied to an input terminal. A divider divides an output signal of the VCO. A phase comparator compares the output of the divider with a reference clock signal and outputs a voltage corresponding to a phase difference. A loop filter is provided on a path leading from an output terminal of the phase comparator to the input terminal of the VCO, and the loop filter removes a high-frequency component of an output voltage of the phase comparator. A terminal for inputting a modulation signal is provided in the loop filter, separately from a terminal connected with the path leading from the output terminal of the phase comparator to the input terminal of the VCO.
    Type: Grant
    Filed: February 15, 2007
    Date of Patent: February 23, 2010
    Assignee: Rohm Co., Ltd.
    Inventor: Takeshi Sagara
  • Publication number: 20090268916
    Abstract: An FM transmitter improved in degree of freedom of selecting components.
    Type: Application
    Filed: June 27, 2006
    Publication date: October 29, 2009
    Applicants: NIIGATA SEIMITSU CO., LTD., RICOH COMPANY, LTD.
    Inventor: Hiroshi Miyagi
  • Publication number: 20090225990
    Abstract: A clock generating circuit having a simple constitution and an audio system are disclosed. The clock generating circuit (300) comprises an oscillator (12) for generating a reference frequency signal by means of a crystal oscillator (10) of a resonance frequency of 32.
    Type: Application
    Filed: April 25, 2006
    Publication date: September 10, 2009
    Applicants: NIIGATA SEIMITSU CO., LTD., RICOH COMPANY, LTD.
    Inventor: Hiroshi Miyagi
  • Patent number: 7557862
    Abstract: An integrated digital BTSC encoder is implemented on a single CMOS integrated circuit chip with an all digital RF modulator. A set top box is provided that allows for a fully integrated solution which may be used with legacy television systems and also with other audio/visual equipment connected to the set top box.
    Type: Grant
    Filed: February 23, 2004
    Date of Patent: July 7, 2009
    Assignee: Broadcom Corporation
    Inventors: Amy Hundhausen, Hosahalli Srinivas, Gopal Venkatesan, Erik Berg
  • Publication number: 20090028346
    Abstract: A digitized FM (frequency modulation) stereo multiplexing circuit for an FM stereo transmitter has a digital audio I/O interface, a digitized FM stereo multiplexing circuit, a low-pass filter and an FM circuit. When a digital audio data is inputted, a digital audio decoder decodes the digital audio data to acquire left and right channel audio signals. The left and right channel audio signals are inputted to an over-sampling unit circuits to process sampling and then to output to an FM stereo multiplexer. The FM stereo multiplexer then generates a master signal and a secondary signal by processing the sampled left and right channel audio signals. In the meanwhile a switch signal and a pilot signal are acquired with an address counter to output from a memory unit. Then the master signal, the secondary signal and the pilot signal are combined as the digital FM stereo data.
    Type: Application
    Filed: January 23, 2008
    Publication date: January 29, 2009
    Inventors: Tain-Rein Chen, Wan-Jung Lin, Shih-Bin Wen, Chien-Shan Chiang
  • Patent number: 7474707
    Abstract: A method of processing a baseband multiplex signal comprises the steps of frequency modulating the baseband multiplex signal to produce a first modulated signal, filtering the first modulated signal to produce a first filtered signal, demodulating the filtered signal to produce a demodulated baseband multiplex signal, correcting the demodulated baseband multiplex signal to reduce or eliminate distortion in a predetermined frequency range of the demodulated baseband multiplex signal to produce a corrected signal, and frequency modulating the corrected signal to produce a second modulated signal. An apparatus that operates in accordance with the method is also provided.
    Type: Grant
    Filed: September 9, 2004
    Date of Patent: January 6, 2009
    Assignee: iBiquity Digital Corporation
    Inventor: Brian William Kroeger
  • Publication number: 20090002198
    Abstract: A marine throttle mounted stereo control system consisting of a throttle mounting base having a control shaft pivotally mounted to the mounting base, which is mounted adjacent an operators seat within a boat cockpit. The throttle control has a stereo control which is remotely located from the boats stereo audio system.
    Type: Application
    Filed: June 27, 2007
    Publication date: January 1, 2009
    Inventor: Darren A. Bach
  • Publication number: 20080285761
    Abstract: A pre-emphasis filter emphasizes a high-frequency component of an input audio signal. A limiter circuit detects that the output signal from the pre-emphasis filter reaches a predetermined upper limit level. A filter adjusting circuit changes the frequency characteristic of the pre-emphasis filter when a limit operation is generated in the limiter circuit.
    Type: Application
    Filed: January 23, 2008
    Publication date: November 20, 2008
    Applicant: ROHM CO., LTD.
    Inventors: Tatsuya MANO, Koji SAITO, Hisashi FURUMOTO
  • Publication number: 20080260165
    Abstract: A digital modulator performs BPSK on differential data, filters it, and outputs the resultant data. A determining unit determines a combination of continuous two values of differential data. In a waveform generator, waveform generation rules are set for each of the combinations. On the basis of the waveform generation rule corresponding to the combination determined by the data determining unit, the waveform generator sequentially outputs a digital waveform signal.
    Type: Application
    Filed: February 4, 2008
    Publication date: October 23, 2008
    Applicant: ROHM CO., LTD.
    Inventors: Koji SAITO, Hisashi FURUMOTO
  • Patent number: 7428308
    Abstract: Apparatus and method for transmitting and reproducing stereophonic audio signals are disclosed. The method comprises splitting first and second channels into two frequency bands, combining the lower frequency band signals of the two channels, and transmitting the combined signals of the two channels or signals representative thereof. The apparatus comprises: a splitter for splitting each of the two channels into two frequency bands, a combiner, for combining the lower frequency band signals of the two channels, and a transmitter for transmitting the combined signals, or signals representative thereof, and the higher frequency band signals of the two channels, or signals representative thereof.
    Type: Grant
    Filed: January 10, 2003
    Date of Patent: September 23, 2008
    Assignee: Zarlink Semiconductor Limited
    Inventors: Marcus Richard Jones, Terence Christopher Aliwell