Patents by Inventor Loke Tan

Loke Tan 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).

  • Patent number: 9560420
    Abstract: The present invention is an integrated cable modem tuner. In one embodiment, the upstream path and the downstream path are integrated on a common semiconductor substrate. The down-stream path can include a TV tuner and digital receiver portion that is integrated on a common semiconductor substrate with the power amplifier of the upstream path. In another embodiment, the TV tuner is implemented on a first semiconductor substrate and the digital receiver portion and the power amplifier are configured on a second semiconductor substrate. However, the two substrates are mounted on a common carrier so that the cable modem appears to be a single chip configuration to the user.
    Type: Grant
    Filed: November 4, 2013
    Date of Patent: January 31, 2017
    Assignee: Broadcom Corporation
    Inventors: Donald G. McMullin, Lawrence M. Burns, Leonard Dauphinee, Ramon A. Gomez, Loke Tan
  • Patent number: 9106242
    Abstract: A method and apparatus is disclosed to compensate for impairments within a data converter such that its output is a more accurate representation of its input. The data converter includes a main data converter, a reference data converter, and a correction module. The main data converter may be characterized as having the impairments. As a result, the output of the main data converter is not the most accurate representation of its input. The reference data converter is designed such that the impairments are not present. The correction module estimates the impairments present within the main data converter using its output and the reference data converter to generate corrections coefficients. The correction module adjusts the output of the main data converter using the corrections coefficients to improve the performance of the data converter.
    Type: Grant
    Filed: April 22, 2013
    Date of Patent: August 11, 2015
    Assignee: Broadcom Corporation
    Inventors: Ramon Gomez, Loke Tan, Bruce Currivan, Steven Jaffe, Thomas Kolze, Lin He
  • Patent number: 9042436
    Abstract: An apparatus is disclosed to compensate for non-linear effects resulting from the transmitter, the receiver, and/or the communication channel in a communication system. A receiver of the communication system contains an image cancellation module that compensates for images generated during the modulation and/or demodulation process. The image cancellation module includes a fine carrier correction loop to correct for frequency offsets between the transmitter and receiver. The image cancellation module includes a coarse acquisition mode and a decision directed mode. The decision directed mode allows for a larger signal-to-noise ratio for the receiver when compared against the coarse acquisition mode.
    Type: Grant
    Filed: March 26, 2013
    Date of Patent: May 26, 2015
    Assignee: Broadcom Corporation
    Inventors: Bruce J. Currivan, Loke Tan, Thomas Kolze, Hanli Zou, Lin He
  • Patent number: 9030341
    Abstract: Various multi-lane ADCs are disclosed that substantially compensate for impairments present within various signals that result from various impairments, such as phase offset, amplitude offset, and/or DC offset to provide some examples, such that their respective digital output samples accurately represent their respective analog inputs. Generally, the various multi-lane ADCs determine various statistical relationships, such as various correlations to provide an example, between these various signals and various known calibration signals to quantify the phase offset, amplitude offset, and/or DC offset that may be present within the various signals. The various multi-lane ADCs adjust the various signals to substantially compensate for the phase offset, amplitude offset, and/or DC offset based upon these various statistical relationships such that their respective digital output samples accurately represent their respective analog inputs.
    Type: Grant
    Filed: July 19, 2012
    Date of Patent: May 12, 2015
    Assignee: Broadcom Corporation
    Inventors: Loke Tan, Steven Jaffe, Hong Liu, Lin He, Randall Perlow, Peter Cangiane, Ramon Gomez, Giuseppe Cusmai
  • Patent number: 8907825
    Abstract: Imbalance and distortion cancellation for composite analog to digital converter (ADC). Such an ‘ADC’ is implemented using two or more ADCs may be employed for sampling (e.g., quantizing, digitizing, etc.) of an analog (e.g., continuous time) signal in accordance with generating a digital (e.g., discrete time) signal. Using at least two ADCs allows for the accommodation and sampling of various signals having a much broader dynamic range without suffering degradation in signal to noise ratio (SNR). Generally, the signal provided via at least one of the paths corresponding to at least one of the respective ADCs is scaled (e.g., attenuated), so that the various ADCs effectively sample signals of different magnitudes. The ADCs may respectively correspond to different magnitude and/or power levels (e.g., high power, lower power, any intermediary power level, etc.). Various implementations of compensation may be performed along the various paths corresponding to the respective ADCs.
    Type: Grant
    Filed: May 29, 2011
    Date of Patent: December 9, 2014
    Assignee: Broadcom Corporation
    Inventors: Thomas J. Kolze, Bruce J. Currivan, Ramon Gomez, Loke Tan, Lin He
  • Patent number: 8732788
    Abstract: The present invention is an integrated set-top box. In one embodiment, the up-stream path and the down-stream path are integrated on a common semiconductor substrate. The down-stream path can include a TV tuner and a digital receiver portion that is integrated on the common semiconductor substrate with a power amplifier of the up-stream path. In another embodiment, the TV tuner is implemented on a first semiconductor substrate and the digital receiver portion and the power amplifier are configured on a second semiconductor substrate. However, the two substrates are mounted on a common carrier so that the set-top box appears to be a single chip configuration to the user.
    Type: Grant
    Filed: May 20, 2005
    Date of Patent: May 20, 2014
    Assignee: Broadcom Corporation
    Inventors: Donald G. McMullin, Lawrence M. Burns, Leonard Dauphinee, Ramon A. Gomez, Loke Tan
  • Publication number: 20140059632
    Abstract: The present invention is an integrated cable modem tuner. In one embodiment, the upstream path and the downstream path are integrated on a common semiconductor substrate. The down-stream path can include a TV tuner and digital receiver portion that is integrated on a common semiconductor substrate with the power amplifier of the upstream path. In another embodiment, the TV tuner is implemented on a first semiconductor substrate and the digital receiver portion and the power amplifier are configured on a second semiconductor substrate. However, the two substrates are mounted on a common carrier so that the cable modem appears to be a single chip configuration to the user.
    Type: Application
    Filed: November 4, 2013
    Publication date: February 27, 2014
    Applicant: Broadcom Corporation
    Inventors: Donald G. McMULLIN, Lawrence M. Burns, Leonard Dauphinee, Ramon A. Gomez, Loke Tan
  • Publication number: 20140002284
    Abstract: Various multi-lane ADCs are disclosed that substantially compensate for impairments present within various signals that result from various impairments, such as phase offset, amplitude offset, and/or DC offset to provide some examples, such that their respective digital output samples accurately represent their respective analog inputs. Generally, the various multi-lane ADCs determine various statistical relationships, such as various correlations to provide an example, between these various signals and various known calibration signals to quantify the phase offset, amplitude offset, and/or DC offset that may be present within the various signals. The various multi-lane ADCs adjust the various signals to substantially compensate for the phase offset, amplitude offset, and/or DC offset based upon these various statistical relationships such that their respective digital output samples accurately represent their respective analog inputs.
    Type: Application
    Filed: July 19, 2012
    Publication date: January 2, 2014
    Applicant: Broadcom Corporation
    Inventors: Loke TAN, Steven Jaffe, Hong Liu, Lin He, Randall Perlow, Peter Cangiane, Ramon Gomez, Giuseppe Cusmai
  • Publication number: 20130314261
    Abstract: A method and apparatus is disclosed to compensate for impairments within a data converter such that its output is a more accurate representation of its input. The data converter includes a main data converter, a reference data converter, and a correction module. The main data converter may be characterized as having the impairments. As a result, the output of the main data converter is not the most accurate representation of its input. The reference data converter is designed such that the impairments are not present. The correction module estimates the impairments present within the main data converter using its output and the reference data converter to generate corrections coefficients. The correction module adjusts the output of the main data converter using the corrections coefficients to improve the performance of the data converter.
    Type: Application
    Filed: April 22, 2013
    Publication date: November 28, 2013
    Applicant: Broadcom Corporation
    Inventors: Ramon GOMEZ, Loke TAN, Bruce CURRIVAN, Steven JAFFE, Thomas KOLZE, Lin HE
  • Patent number: 8578434
    Abstract: The present invention is an integrated cable modem tuner. In one embodiment, the upstream path and the downstream path are integrated on a common semiconductor substrate. The down-stream path can include a TV tuner and digital receiver portion that is integrated on a common semiconductor substrate with the power amplifier of the upstream path. In another embodiment, the TV tuner is implemented on a first semiconductor substrate and the digital receiver portion and the power amplifier are configured on a second semiconductor substrate. However, the two substrates are mounted on a common carrier so that the cable modem appears to be a single chip configuration to the user.
    Type: Grant
    Filed: May 20, 2005
    Date of Patent: November 5, 2013
    Assignee: Broadcom Corporation
    Inventors: Donald G. McMullin, Lawrence M. Burns, Leonard Dauphinee, Ramon A. Gomez, Loke Tan
  • Publication number: 20130085703
    Abstract: Embodiments provide histogram-based methods and system to estimate the transfer function of an ADC, and subsequently to linearize a non-linear ADC transfer function. Embodiments include blind algorithms that require no a priori knowledge of the input signal distribution. Embodiments can be implemented using cumulative (i.e., cumulative distribution function (CDF)) or non-cumulative (i.e., probability density function (PDF)) histograms. According to embodiments, a non-linear transfer function can be estimated by linearly approximating successive local intervals of the transfer function. Linearly approximated successive local intervals of the transfer function can then be used to fully characterize and closely estimate the transfer function.
    Type: Application
    Filed: September 30, 2011
    Publication date: April 4, 2013
    Applicant: Broadcom Corporation
    Inventors: Ray (Ramon) GOMEZ, Bruce J. Currivan, Lin He, Loke Tan, Frank Van der Goes, Cy (Chun-Ying) Chen, Jiangfeng Wu, Thomas Kolze
  • Patent number: 8239914
    Abstract: A highly integrated set-top box is implemented on a single semiconductor substrate. For instance, an analog RF tuner is implemented on the same substrate with a digital receiver, and audio-video back-end circuits. The single chip set-top box can be used for satellite, cable, internet, or terrestrial TV applications, or other applications. As a result, the substrate area, assembly time, and associated costs per chip are reduced.
    Type: Grant
    Filed: July 22, 2005
    Date of Patent: August 7, 2012
    Assignee: Broadcom Corporation
    Inventors: Martin Kuhlmann, Ramon A. Gomez, Loke Tan
  • Patent number: 8208530
    Abstract: An apparatus and method for correcting IQ imbalance are presented. An exemplary receiver for processing I and Q signals from a tuner includes: a non-decision directed (NDD) imbalance canceller coupled to receive the I and Q signals, and a decision directed (DD) imbalance canceller coupled to the non-decision directed imbalance canceller. The DD imbalance canceller converges after the NDD imbalance canceller converges, so as to correct IQ imbalances in the receiver. An exemplary method for processing I and Q signals from a tuner includes: (a) converging a NDD imbalance canceller to correct a majority of IQ imbalances, and (b) subsequently converging a DD imbalance canceller to correct a remainder of IQ imbalances not corrected in step (a). The apparatus and method correct frequency-dependent and frequency-independent IQ imbalances.
    Type: Grant
    Filed: January 19, 2006
    Date of Patent: June 26, 2012
    Assignee: Broadcom Corporation
    Inventors: Loke Tan, Hanli Zou, William Ngai
  • Publication number: 20110227768
    Abstract: Imbalance and distortion cancellation for composite analog to digital converter (ADC). Such an ‘ADC’ is implemented using two or more ADCs may be employed for sampling (e.g., quantizing, digitizing, etc.) of an analog (e.g., continuous time) signal in accordance with generating a digital (e.g., discrete time) signal. Using at least two ADCs allows for the accommodation and sampling of various signals having a much broader dynamic range without suffering degradation in signal to noise ratio (SNR). Generally, the signal provided via at least one of the paths corresponding to at least one of the respective ADCs is scaled (e.g., attenuated), so that the various ADCs effectively sample signals of different magnitudes. The ADCs may respectively correspond to different magnitude and/or power levels (e.g., high power, lower power, any intermediary power level, etc.). Various implementations of compensation may be performed along the various paths corresponding to the respective ADCs.
    Type: Application
    Filed: May 29, 2011
    Publication date: September 22, 2011
    Applicant: BROADCOM CORPORATION
    Inventors: Thomas J. Kolze, Bruce J. Currivan, Ramon Gomez, Loke Tan, Lin He
  • Patent number: 8009075
    Abstract: A method and apparatus is disclosed to extend a dynamic input range of an analog to digital converter (ADC). A composite ADC may include one or more ADCs. The one or more ADCs compare a signal metric of an analog input signal to quantization levels to produce intermediate digital output signals using one or more non-clipping input values. The composite ADC may select among the one or more intermediate digital output signals based on the signal metric of the analog input signal to produce a final digital output.
    Type: Grant
    Filed: May 11, 2009
    Date of Patent: August 30, 2011
    Assignee: Broadcom Corporation
    Inventors: Bruce J. Currivan, Thomas J. Kolze, Lin He, Loke Tan, Ramon Gomez, Francesco Gatta
  • Patent number: 7978795
    Abstract: An apparatus comprising a slicer configured to produce a symbol decision value and a symbol error value utilizing, at least in part, a slicer input signal; and an automatic gain controller configured to facilitate the automatic control of a gain applied to the slicer input signal by producing a gain control signal, the automatic gain controller comprising a decision-directed amplitude error detector configured to utilize, at least in part, the symbol decision value and the symbol error value to produce an amplitude error signal, and a loop filter configured to utilize the amplitude error signal to produce the gain control signal.
    Type: Grant
    Filed: November 27, 2007
    Date of Patent: July 12, 2011
    Assignee: Broadcom Corporation
    Inventors: Bruce Currivan, Loke Tan, Thomas Kolze
  • Patent number: 7952502
    Abstract: Imbalance and distortion cancellation for composite analog to digital converter (ADC). Such an ‘ADC’ is implemented using two or more ADCs may be employed for sampling (e.g., quantizing, digitizing, etc.) of an analog (e.g., continuous time) signal in accordance with generating a digital (e.g., discrete time) signal. Using at least two ADCs allows for the accommodation and sampling of various signals having a much broader dynamic range without suffering degradation in signal to noise ratio (SNR). Generally, the signal provided via at least one of the paths corresponding to at least one of the respective ADCs is scaled (e.g., attenuated), so that the various ADCs effectively sample signals of different magnitudes. The ADCs may respectively correspond to different magnitude and/or power levels (e.g., high power, lower power, any intermediary power level, etc.). Various implementations of compensation may be performed along the various paths corresponding to the respective ADCs.
    Type: Grant
    Filed: November 18, 2010
    Date of Patent: May 31, 2011
    Assignee: Broadcom Corporation
    Inventors: Thomas J. Kolze, Bruce J. Currivan, Ramon Gomez, Loke Tan, Lin He
  • Publication number: 20110063148
    Abstract: Imbalance and distortion cancellation for composite analog to digital converter (ADC). Such an ‘ADC’ is implemented using two or more ADCs may be employed for sampling (e.g., quantizing, digitizing, etc.) of an analog (e.g., continuous time) signal in accordance with generating a digital (e.g., discrete time) signal. Using at least two ADCs allows for the accommodation and sampling of various signals having a much broader dynamic range without suffering degradation in signal to noise ratio (SNR). Generally, the signal provided via at least one of the paths corresponding to at least one of the respective ADCs is scaled (e.g., attenuated), so that the various ADCs effectively sample signals of different magnitudes. The ADCs may respectively correspond to different magnitude and/or power levels (e.g., high power, lower power, any intermediary power level, etc.). Various implementations of compensation may be performed along the various paths corresponding to the respective ADCs.
    Type: Application
    Filed: November 18, 2010
    Publication date: March 17, 2011
    Applicant: BROADCOM CORPORATION
    Inventors: Thomas J. Kolze, Bruce J. Currivan, Ramon Gomez, Loke Tan, Lin He
  • Publication number: 20100052967
    Abstract: A method and apparatus is disclosed to extend a dynamic input range of an analog to digital converter (ADC). A composite ADC may include one or more ADCs. The one or more ADCs compare a signal metric of an analog input signal to quantization levels to produce intermediate digital output signals using one or more non-clipping input values. The composite ADC may select among the one or more intermediate digital output signals based on the signal metric of the analog input signal to produce a final digital output.
    Type: Application
    Filed: May 11, 2009
    Publication date: March 4, 2010
    Applicant: Broadcom Corporation
    Inventors: Bruce J. Currivan, Thomas J. Kolze, Lin He, Loke Tan, Ramon Gomez, Francesco Gatta
  • Publication number: 20090135896
    Abstract: An apparatus comprising a slicer configured to produce a symbol decision value and a symbol error value utilizing, at least in part, a slicer input signal; and an automatic gain controller configured to facilitate the automatic control of a gain applied to the slicer input signal by producing a gain control signal, the automatic gain controller comprising a decision-directed amplitude error detector configured to utilize, at least in part, the symbol decision value and the symbol error value to produce an amplitude error signal, and a loop filter configured to utilize the amplitude error signal to produce the gain control signal.
    Type: Application
    Filed: November 27, 2007
    Publication date: May 28, 2009
    Applicant: BROADCOM CORPORATION
    Inventors: Bruce Currivan, Loke Tan, Thomas Kolze