Patents by Inventor Meng Pan

Meng Pan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20090247095
    Abstract: According to one exemplary embodiment, a method of preventing harmonics from causing distortion in a communications system includes feeding a test signal through a pre-distortion circuit in the communications system to a transmitter in the communications system. The method continues by transmitting a distorted output signal produced by the transmitter to an analyzer, analyzing the distorted output signal to identify one or more undesired harmonics, and generating and sending calibration data from the analyzer to calibrate the pre-distortion circuit, thereby preventing the one or more undesired harmonics from causing distortion in the communications system. In one embodiment, a system to prevent harmonics from causing distortion in a communications system includes a pre-distortion circuit, a transmitter, and an analyzer configured to identify one or more undesired harmonics and to generate and send calibration data to prevent the undesired harmonics from causing distortion.
    Type: Application
    Filed: March 25, 2008
    Publication date: October 1, 2009
    Applicant: BROADCOM CORPORATION
    Inventor: Meng-An Pan
  • Patent number: 7596195
    Abstract: The invention enables a reversing IQ polarity in a bandpass filter so that the bandpass filter can filter signals with high side or low side injection.
    Type: Grant
    Filed: June 14, 2004
    Date of Patent: September 29, 2009
    Assignee: Broadcom Corporation
    Inventor: Meng-An Pan
  • Patent number: 7583143
    Abstract: Methods and systems for digitally controlling transmitter gain compensation are disclosed. Aspects of one method may include applying an effective negative resistance to differential outputs of amplifying circuitry to compensate for gain changes that may be due to temperature changes. The effective negative resistance may be provided via a plurality of load circuits coupled in parallel to the differential outputs. The plurality of load circuits may have similar effective negative resistances, or the plurality of load circuits may be binary weighted. Each load circuit may be selected via digital control signals that may enable the load circuit. This may allow adjusting of the effective negative resistance by selecting different load circuits.
    Type: Grant
    Filed: December 28, 2006
    Date of Patent: September 1, 2009
    Assignee: Broadcom Corporation
    Inventor: Meng-An Pan
  • Publication number: 20090197886
    Abstract: This invention is directed to a hexahydro-cycloheptapyrazole cannabinoid modulator compound of formula (I): and a method for use in treating, ameliorating or preventing a cannabinoid receptor mediated syndrome, disorder or disease.
    Type: Application
    Filed: April 7, 2009
    Publication date: August 6, 2009
    Inventors: Fina Liotta, Mingde Xia, Huajun Lu, Meng Pan, Michael P. Wachter
  • Patent number: 7555263
    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: August 8, 2000
    Date of Patent: June 30, 2009
    Assignee: Broadcom Corporation
    Inventors: Ahmadreza Rofougaran, Maryam Rofougaran, Brima Ibrahim, Jacob Rael, Shahla Khorram, Shervin Moloudi, Stephen Wu, Hooman Darabi, William T. Colleran, Ed Chien, Meng-An Pan
  • Patent number: 7554411
    Abstract: A method and apparatus are provided for enabling a transmitter to have a substantially linear magnitude response and a substantially linear phase response. The transmitter includes first and second programmable gain amplifiers (PGAs). The first PGA is tuned to have a resonant frequency that is less than an operating frequency of the first PGA. The second PGA is tuned to have a resonant frequency that is greater than an operating frequency of the second PGA. A magnitude response at an output of the first PGA and a magnitude response at an output of the second PGA combine to provide a substantially linear magnitude response across a frequency range that includes the operating frequency of the first or second PGA. According to an embodiment, the first and second PGAs have the same operating frequency.
    Type: Grant
    Filed: January 23, 2007
    Date of Patent: June 30, 2009
    Assignee: Broadcom Corporation
    Inventor: Meng-An Pan
  • Patent number: 7551029
    Abstract: A transconductance stage providing gain control includes an input stage to convert a first differential input voltage and a second differential input voltage to a first intermediate current and a second intermediate current, respectively. An output stage generates a first output current signal and a second output current signal based on the first and second intermediate currents, respectively. The output stage includes a first plurality of output transistors coupled to a first plurality of corresponding switch resistors and a second plurality of output transistors coupled to a second plurality of corresponding switch resistors. The number of activated switch resistors of the first plurality of switch resistors determines a gain of the first output current signal and a number of activated switch resistors of the second plurality of switch resistors determines a gain of the second output current signal.
    Type: Grant
    Filed: March 10, 2006
    Date of Patent: June 23, 2009
    Assignee: Broadcom Corporation
    Inventor: Meng-An Pan
  • Publication number: 20090154597
    Abstract: A transmitter includes a dual mode modulator and an amplifier coupled to the dual mode modulator. The dual mode modulator implements a linear modulation scheme during a first mode of the modulator to produce a variable envelope modulated signal. The dual mode modulator implements a non-linear modulation scheme during a second mode of the modulator to produce a constant envelope modulated signal. The amplifier is biased as a linear amplifier during the first mode of the modulator and is biased as a non-linear amplifier during the second mode of the modulator. A feed-forward connection between the dual mode modulator and the amplifier is used to indicate a change in modulation mode and to adjust the bias of the amplifier. A power of the constant envelope modulated signal is increased such that an operating point of the amplifier remains substantially constant during the first and second modes of the modulator.
    Type: Application
    Filed: January 5, 2009
    Publication date: June 18, 2009
    Applicant: Broadcom Corporation
    Inventor: Meng-An PAN
  • Patent number: 7548733
    Abstract: A method and apparatus are provided for enabling a transmitter to have a substantially linear magnitude response and a substantially linear phase response. The transmitter includes first and second power amplifier drivers (PADs) having respective first and second non-linear phase responses. The first non-linear phase response is based on a first bias applied to the first PAD, and the second non-linear phase response is based on a second bias applied to the second PAD. The first and second PADs are coupled in parallel to provide a combined substantially linear phase response. According to an embodiment, the first and second PADs have respective first and second average input capacitances. Signal swings about the first and second biases vary the respective first and second average input capacitances, which may be combined to provide a combined average input capacitance that is substantially insensitive to the signal swings about the first and second biases.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: June 16, 2009
    Assignee: Broadcom Corporation
    Inventor: Meng-An Pan
  • Publication number: 20090137213
    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: Application
    Filed: November 18, 2008
    Publication date: May 28, 2009
    Applicant: Broadcom Corporation
    Inventors: Ahmadreza Rofougaran, Maryam Rofougaran, Jacob Rael, Syed Masood, Brima Ibrahim, Hung-Ming Chien, Stephen Wu, Meng-An Pan
  • Publication number: 20090099143
    Abstract: This invention is directed to a tetrahydro-indazole cannabinoid modulator compound of formula I: and a method for use in treating, ameliorating or preventing a cannabinoid receptor mediated syndrome, disorder or disease.
    Type: Application
    Filed: October 8, 2008
    Publication date: April 16, 2009
    Inventors: Bharat Lagu, Fina Liotta, Meng Pan, Michael P. Wachter, Mingde Xia Xia
  • Patent number: 7512378
    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: July 20, 2007
    Date of Patent: March 31, 2009
    Assignee: Broadcom Corporation
    Inventors: Ahmadreza Rofougaran, Maryam Rofougaran, Meng-An Pan, Hung-Ming Chien, Shahla Khorram, William T. Colleran, Jacob Rael, Masood Syed, Brima Ibrahim, Stephen Wu, Shervin Moloudi
  • Publication number: 20090048235
    Abstract: This invention is directed to a cannabinoid modulator compound of formula (I): or a form thereof, and methods for use in treating, ameliorating or preventing a cannabinoid receptor mediated syndrome, disorder or disease.
    Type: Application
    Filed: August 11, 2008
    Publication date: February 19, 2009
    Inventors: Mingde Xia, Meng Pan, Michael P. Wachter
  • Publication number: 20090010310
    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: Application
    Filed: July 31, 2008
    Publication date: January 8, 2009
    Applicant: Broadcom Corporation
    Inventors: Ahmadreza Rofougaran, Maryam Rofougaran, Meng-An Pan, Hung-Ming Chien, Shahla Khorram, William T. Colleran, Jacob Rael, Masood Syed, Brima Ibrahim, Stephen Wu, Shervin Moloudi
  • Patent number: 7474880
    Abstract: A transmitter includes a dual mode modulator and an amplifier coupled to the dual mode modulator. The dual mode modulator implements a linear modulation scheme during a first mode of the modulator to produce a variable envelope modulated signal. The dual mode modulator implements a non-linear modulation scheme during a second mode of the modulator to produce a constant envelope modulated signal. The amplifier is biased as a linear amplifier during the first mode of the modulator and is biased as a non-linear amplifier during the second mode of the modulator. A feed-forward connection between the dual mode modulator and the amplifier is used to indicate a change in modulation mode and to adjust the bias of the amplifier. A power of the constant envelope modulated signal is increased such that an operating point of the amplifier remains substantially constant during the first and second modes of the modulator.
    Type: Grant
    Filed: March 24, 2005
    Date of Patent: January 6, 2009
    Assignee: Broadcom Corporation
    Inventor: Meng-An Pan
  • Patent number: 7463868
    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: April 19, 2005
    Date of Patent: December 9, 2008
    Assignee: Broadcom Corporation
    Inventors: Ahmadreza Rofougaran, Maryam Rofougaran, Jacob Rael, Syed Masood, Brima Ibrahim, Hung-Ming Chien, Stephen Wu, Meng-An Pan
  • Patent number: 7452997
    Abstract: This invention is directed to a tetrahydro-indazole cannabinoid modulator compound of formula I: and a method for use in treating, ameliorating or preventing a cannabinoid receptor mediated syndrome, disorder or disease.
    Type: Grant
    Filed: March 23, 2005
    Date of Patent: November 18, 2008
    Assignee: Janssen Pharmaceutica, N.V.
    Inventors: Bharat Lagu, Fina Liotta, Meng Pan, Michael P. Wachter, Mingde Xia Xia
  • Patent number: 7440732
    Abstract: A transmitter includes a first mixer to generate a first output signal by up-converting a first baseband signal having a first DC offset component. A second mixer generates a second output signal by up-converting a second baseband signal having a second DC offset component. The second output signal is subtracted from the first output signal to generate a transmitter output signal. The transmitter output signal includes a local oscillator (LO) leakage signal caused by the first and/or second DC offset components. A third mixer produces a third output signal by up-converting the first DC offset component. A fourth mixer produces a fourth output signal by up-converting the second DC offset component. The fourth output signal is subtracted from the third output signal to generate a LO leakage cancellation signal. The LO leakage cancellation signal is subtracted from the transmitter output signal, thereby reducing a power of the LO leakage signal.
    Type: Grant
    Filed: August 26, 2005
    Date of Patent: October 21, 2008
    Assignee: Broadcom Corporation
    Inventor: Meng-An Pan
  • Publication number: 20080139139
    Abstract: Methods and systems for a transmitter LOFT cancellation scheme that maintains IQ balance are disclosed. Aspects of one method may include providing current compensation to both differential inputs of a mixer for each of I and Q channels. An initial current compensation of X units may be provided, followed by subsequent compensation as needed. The initial compensation may be provided to each differential input of the mixers used for I and Q channels. The subsequent current compensation for the I channel may be independent of the subsequent current compensation for the Q channel. Subsequent current compensation to a first differential input for a mixer may be increased by Y units while decreasing current compensation to the second differential input of the mixer by Y units. In this manner, the DC common mode level for the mixer may remain the same at the initial DC compensation current of X units for both mixers.
    Type: Application
    Filed: December 28, 2006
    Publication date: June 12, 2008
    Inventor: Meng-An Pan
  • Publication number: 20080139132
    Abstract: Various aspect of a system for a linearized transmitter including a power amplifier may include at least one transconductance amplifier that enables generation of a single analog quadrature signal. Transmitter mixers may enable generation of a plurality of upconverted RF signals in a corresponding plurality of RF processing chains based on the generated single analog quadrature signal. In various embodiments of the invention, a gain stage, for example gain stage, may also be referred to as an RF processing chain. Power amplifier circuit may enable generation of a corresponding plurality of RF output signals within a wireless communication system based on the generated plurality of upconverted RF signals.
    Type: Application
    Filed: June 13, 2007
    Publication date: June 12, 2008
    Inventors: Meng-An Pan, Ali Afsahi, Vikram Magoon, Arya Behzad