Patents by Inventor Paul Cheng-Po Liang

Paul Cheng-Po Liang 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: 9160462
    Abstract: A communications apparatus is disclosed. A first radio module provides a first wireless communications service and communicates with a first communications device in compliance with a first protocol. A second radio module provides a second wireless communications service and communicates with a second communications device in compliance with a second protocol. A transmission noise suppression device is operative to process downlink signals received by the first radio module to cancel transmission noise comprised in the downlink signals, where the transmission noise is generated when the second radio module is processing uplink signals to be transmitted.
    Type: Grant
    Filed: February 26, 2013
    Date of Patent: October 13, 2015
    Assignee: MEDIATEK INC.
    Inventors: Chih-Yuan Lin, Qiang Zhou, Charles Chien, Paul Cheng Po Liang, Wen-Wei Yang
  • Patent number: 9118535
    Abstract: A method of configuring at least one frequency dependent (FD), in-phase/quadrature (I/Q), imbalance compensation filter within a radio frequency (RF) module is described. The method includes applying an input signal to an input of the RF module, receiving a filtered I-path signal for the RF module and deriving at least one I-path filtering estimate value therefrom, receiving a filtered Q-path signal for the RF module and deriving at least one Q-path filtering estimate value therefrom, and configuring the at least one FD I/Q imbalance compensation filter based at least partly on at least one ratio between the derived I-path and Q-path filtering estimate values.
    Type: Grant
    Filed: March 12, 2014
    Date of Patent: August 25, 2015
    Assignee: MediaTek Singapore Pte. Ltd.
    Inventors: Balachander Narasimhan, Charles Chien, Sheng-Hong Yan, Paul Cheng Po Liang
  • Publication number: 20150236729
    Abstract: A communication unit comprises a radio frequency, RF, transmitter comprising: a power amplifier, PA, module; an envelope tracking system operably coupled to the PA module and arranged to variably control a supply voltage for the PA module; and a load control system operably coupled to an output of the PA module and arranged to control a power amplifier output load.
    Type: Application
    Filed: February 16, 2014
    Publication date: August 20, 2015
    Applicant: MEDIATEK INC.
    Inventors: Chia-Sheng Peng, Wei-Cheng Liu, Sheng-Hong Yan, Paul Cheng Po Liang
  • Publication number: 20150236877
    Abstract: A communication unit comprises a radio frequency, RF, transmitter comprising: a power amplifier, PA, module; an envelope tracking system operably coupled to the PA module and arranged to variably control a supply voltage for the PA module; and a load control system operably coupled to an output of the PA module and arranged to control a power amplifier output load.
    Type: Application
    Filed: February 14, 2014
    Publication date: August 20, 2015
    Applicant: MEDIATEK INC.
    Inventors: Chia-Sheng Peng, Wei-Cheng Liu, Sheng-Hong Yan, Paul Cheng Po Liang
  • Patent number: 9100078
    Abstract: A radio frequency (RF) receiver includes a digital tuning engine; I-path and Q-path analog filters, tuned by the digital tuning engine; and a digital compensation circuit. The digital tuning engine executes a RC (resistor-capacitor) time constant calibration to adjust respective cut-off frequencies of the I-path analog filter and the Q-path analog filter. The digital tuning engine executes a filter mismatch calibration to match the I-path analog filter and the Q-path analog filter. The digital tuning engine executes a filter residual mismatch calibration to match an I-path response from the I-path analog filter to the digital compensation circuit and a Q-path response from the Q-path analog filter to the digital compensation circuit.
    Type: Grant
    Filed: March 13, 2013
    Date of Patent: August 4, 2015
    Assignee: MEDIATEK INC.
    Inventors: Sheng-Hong Yan, Sheng-Hao Chen, Paul Cheng Po Liang, Jen-Che Tsai
  • Patent number: 9088319
    Abstract: A radio frequency (RF) transmitter architecture includes at least one digital signal processing module. The at least one digital signal processing module is configurable to operate in at least a first mode wherein the at least one digital signal processing module is arranged to receive a digital input signal, select, from a reduced set of digital power amplifier (DPA) control values, a plurality of DPA control values based at least partly on the received digital input signal, perform interpolation of the plurality of selected DPA control values to determine a DPA control value from a non-reduced set of DPA control values representative of the received digital input signal, and output to at least one DPA component the determined DPA control value representative of the received digital input signal.
    Type: Grant
    Filed: April 20, 2012
    Date of Patent: July 21, 2015
    Assignee: MediaTek Singapore Pte. Ltd.
    Inventors: Chun-Hsien Peng, Julia Liu, Chao Lu, Hua Wang, Paul Cheng Po Liang
  • Publication number: 20140376420
    Abstract: A communications apparatus has a transmitter path and a training signal generator. The transmitter path is arranged for transmitting a transmission signal. The training signal generator is arranged for generating a training signal in a receiver band, and injecting the training signal to the transmitter path. The training signal is utilized to obtain an accurate estimation of the channel which helps to suppress transmission noise comprised in at least one received signal of the communications apparatus, and the transmission noise is generated by the transmitter path. Specifically, the communications apparatus further has a receiver path and a transmission noise suppression device. The receiver path is arranged for receiving a received signal. The transmission noise suppression device is arranged for receiving the training signal, and processing the received signal to suppress transmission noise comprised in the received signal according to at least the training signal.
    Type: Application
    Filed: December 19, 2013
    Publication date: December 25, 2014
    Applicant: MediaTek Singapore Pte. Ltd.
    Inventors: Qiang Zhou, Balachander Narasimhan, Charles Chien, Jonathan Richard STRANGE, Paul Cheng Po Liang
  • Publication number: 20140355717
    Abstract: A radio frequency transmitter includes a digital power amplifier and a bias control circuit. The digital power amplifier is arranged for receiving at least a radio frequency input signal, a digital amplitude control word signal and at least one bias voltage to generate a radio frequency output signal. The bias control circuit is coupled to the digital power amplifier, and is arranged for adjusting the at least one bias voltage according to a power control signal.
    Type: Application
    Filed: April 15, 2014
    Publication date: December 4, 2014
    Applicant: MEDIATEK INC.
    Inventors: Chao Lu, Chun-Hsien Peng, Paul Cheng Po Liang
  • Publication number: 20140314184
    Abstract: A wireless transmitter has a digital baseband module and a radio-frequency (RF) transmitter. The digital baseband module generates a multi-mode modulated signal by using a plurality of digital synthesizers. The RF transmitter has a frequency synthesizer and a digital power amplifier (DPA). The frequency synthesizer generates an oscillation signal with an RF carrier frequency. The DPA generates a multi-standard RF signal according to the multi-mode modulated signal and the oscillation signal.
    Type: Application
    Filed: December 18, 2013
    Publication date: October 23, 2014
    Applicant: MEDIATEK INC.
    Inventors: Ho-Chi Huang, Chun-Hsien Peng, Paul Cheng Po Liang
  • Publication number: 20140273907
    Abstract: A method of configuring at least one frequency dependent (FD), in-phase/quadrature (I/Q), imbalance compensation filter within a radio frequency (RF) module is described. The method includes applying an input signal to an input of the RF module, receiving a filtered I-path signal for the RF module and deriving at least one I-path filtering estimate value therefrom, receiving a filtered Q-path signal for the RF module and deriving at least one Q-path filtering estimate value therefrom, and configuring the at least one FD I/Q imbalance compensation filter based at least partly on at least one ratio between the derived I-path and Q-path filtering estimate values.
    Type: Application
    Filed: March 12, 2014
    Publication date: September 18, 2014
    Applicant: MediaTek Singapore Pte. Ltd.
    Inventors: Balachander Narasimhan, Charles Chien, Sheng-Hong Yan, Paul Cheng Po Liang
  • Publication number: 20140187182
    Abstract: A method of calibrating an envelope tracking system for a supply voltage for a power amplifier module within a radio frequency (RF) transmitter of a wireless communication unit is described. The method comprising, within at least one signal processing module of the wireless communication unit, applying a training signal comprising an envelope that varies with time to an input of the RF transmitter, receiving at least an indication of instantaneous output signal values for the power amplifier module in response to the training signal, calculating instantaneous gain values based at least partly on the received output power values, and adjusting a mapping function between an instantaneous envelope of a waveform signal to be amplified by the power amplifier module and the power amplifier module supply voltage to achieve a power amplifier module gain, for example that is monotonically increasing as a function of power amplifier output power.
    Type: Application
    Filed: August 1, 2013
    Publication date: July 3, 2014
    Applicant: MEDIATEK INC.
    Inventors: Sheng-Hong Yan, Paul Cheng Po Liang
  • Patent number: 8766838
    Abstract: A method and apparatus for performing modulation of a radio frequency, RF, signal within a digital-to-RF converter. The method includes determining a desired digital control word switching frequency value based at least partly on at least one parameter corresponding to a bandwidth of the RF signal to be modulated and at least one from a group including: at least one parameter corresponding to an RF channel frequency of the RF signal to be modulated; and at least one parameter corresponding to a power level of the RF signal to be modulated. The method further includes dynamically configuring at least one digital control module to output at least one digital control word signal in accordance with the desired digital control word switching frequency value, and performing modulation of the RF signal in accordance with the at least one digital control word signal output by the at least one digital control module.
    Type: Grant
    Filed: March 13, 2013
    Date of Patent: July 1, 2014
    Assignee: MediaTek Singapore Pte. Ltd.
    Inventors: Hua Wang, Paul Cheng Po Liang
  • Publication number: 20140177755
    Abstract: A radio frequency (RF) transmitter includes a power amplifier comprising a plurality of power amplifier cells. At least one digital signal processing module of the RF transmitter is operably coupled to the power amplifier and comprises at least one digital pre-distortion component arranged to apply at least one digital pre-distortion codeword to the plurality of power amplifier cells, wherein the at least one digital pre-distortion codeword is applied to at least one of the plurality of power amplifier cells via a digital filter. A combiner is arranged to combine outputs of the plurality of power amplifier cells thereby generating an analogue RF signal for transmission over an RF interface based at least partly on the digitally filtered at least one digital pre-distortion codeword.
    Type: Application
    Filed: August 22, 2013
    Publication date: June 26, 2014
    Applicant: MediaTek Singapore Pte. Ltd.
    Inventors: Chao Lu, Hua Wang, Paul Cheng Po Liang, Sang Won Son
  • Publication number: 20140119416
    Abstract: One communication system includes a first die, a second die and a front-end circuit. The first die has an up-converter and a digital baseband (DBB) processing circuit. The second die has a down-converter. The front-end circuit couples an antenna to the first and second dies. Another exemplary communication system includes a first die, a second die and a front-end circuit. The first die performs digital baseband (DBB) processing, and generates a first signal with a higher frequency according to a second signal, wherein the second signal is derived from an output signal of the DBB processing. The second die generates a third signal with a lower frequency according to a fourth signal. The front-end circuit couples the first signal from the first die to an antenna and couples the fourth signal from the antenna to the second die.
    Type: Application
    Filed: March 13, 2013
    Publication date: May 1, 2014
    Applicant: MEDIATEK INC.
    Inventors: Ho-Chi Huang, Paul Cheng Po Liang
  • Publication number: 20140015701
    Abstract: A method and apparatus for performing modulation of a radio frequency, RF, signal within a digital-to-RF converter. The method includes determining a desired digital control word switching frequency value based at least partly on at least one parameter corresponding to a bandwidth of the RF signal to be modulated and at least one from a group including: at least one parameter corresponding to an RF channel frequency of the RF signal to be modulated; and at least one parameter corresponding to a power level of the RF signal to be modulated. The method further includes dynamically configuring at least one digital control module to output at least one digital control word signal in accordance with the desired digital control word switching frequency value, and performing modulation of the RF signal in accordance with the at least one digital control word signal output by the at least one digital control module.
    Type: Application
    Filed: March 13, 2013
    Publication date: January 16, 2014
    Applicant: Mediatek Singapore Pte. Ltd.
    Inventors: Hua Wang, Paul Cheng Po Liang
  • Publication number: 20130237260
    Abstract: A communications apparatus is disclosed. A first radio module provides a first wireless communications service and communicates with a first communications device in compliance with a first protocol. A second radio module provides a second wireless communications service and communicates with a second communications device in compliance with a second protocol. A transmission noise suppression device is operative to process downlink signals received by the first radio module to cancel transmission noise comprised in the downlink signals, where the transmission noise is generated when the second radio module is processing uplink signals to be transmitted.
    Type: Application
    Filed: February 26, 2013
    Publication date: September 12, 2013
    Applicant: MEDIATEK INC.
    Inventors: Chih-Yuan LIN, Qiang ZHOU, Charles CHIEN, Paul Cheng Po LIANG, Wen-Wei YANG
  • Patent number: 8489046
    Abstract: A multi-mode communications transmitter includes a signal decomposer that converts rectangular-coordinate in-channel and quadrature channel signals into polar-coordinate amplitude and angle component signals and form therefrom first and second modulation signals. The signal decomposition process performed by the signal decomposer combines envelope-reduction and restoration (ERR) with filtering to reduce the bandwidths of the first and second modulation signals compared to the bandwidths of the unmodified amplitude and angle component signals. The reduction in signal bandwidths eases the design requirements of the electrical components needed to process and generate the signals applied to the power supply and radio frequency (RF) input ports of the multi-mode communications transmitter's power amplifier (PA).
    Type: Grant
    Filed: July 21, 2008
    Date of Patent: July 16, 2013
    Assignee: Panasonic Corporation
    Inventors: Paul Cheng-Po Liang, Koji Takinami
  • Patent number: 8385464
    Abstract: A baseband circuit for a communications transmitter includes a baseband modulator, a pulse-shaping filter, and an AMPR reduction circuit. The baseband modulator is configured to generate a sequence of symbols formatted in accordance with a non-constant envelope modulation scheme. The pulse-shaping filter is configured to band-limit the sequence of samples to provide a sequence of samples. The AMPR reduction circuit is configured to analyze and modify one or more samples in the sequence of samples, if a sample in the sequence of samples that has been previously analyzed by the AMPR reduction circuit is determined to have a magnitude less than a predetermined low-magnitude threshold.
    Type: Grant
    Filed: June 11, 2009
    Date of Patent: February 26, 2013
    Assignee: Panasonic Corporation
    Inventors: Paul Cheng-Po Liang, Hua Wang, Kenichi Mori
  • Patent number: 8385469
    Abstract: A low cost high-efficiency all-digital transmitter using all-digital power amplifiers (“DPA”) and various mapping techniques to generate an output signal, which substantially reproduces a baseband signal at a carrier frequency. A baseband signal generator generates a baseband signal which is quantized by a signal processor using a quantization map. A DPA control mapper outputs control signals to phase selectors using the quantized signal and a quantization table. Each phase selector receives one of the control signals and outputs a waveform at a carrier frequency with a phase corresponding to the control signals, or an inactive signal. Each DPA in a DPA array has an assigned weight, receives one of the waveforms from the phase selectors, and outputs a power signal according to the weight of the DPA and the phase of the received waveform. The combined power signal substantially reproduces the baseband signal at the carrier frequency.
    Type: Grant
    Filed: January 20, 2010
    Date of Patent: February 26, 2013
    Assignee: Panasonic Corporation
    Inventors: Hua Wang, Toru Matsuura, Gregoire le Grand de Mercey, Paul Cheng-Po Liang, Koji Takinami, Richard W. D. Booth
  • Patent number: 8351558
    Abstract: The disclosure provides an effective means for fine-resolution determination of the frequency content of an RF signal using low speed digital circuits. The disclosure relates to a method and apparatus for decomposing a high frequency RF signal into several low frequency signals or data streams without loss of any information and without the use of extraneous circuit components such as local oscillators, mixers or offset phase-locked loops. Single or multiple phase oscillator outputs are fed directly to a single or multiple direct RF frequency-to-digital (DrfDC) circuits. The front end of the DrfDC circuit decomposes a high frequency signal into several low frequency signals without loss of any information. The low frequency signals are processed by the back-end of the DrfDC and converted into digital data streams. The digital data streams are then combined and averaged to represent the frequency of the input RF signal.
    Type: Grant
    Filed: September 25, 2009
    Date of Patent: January 8, 2013
    Assignee: Panasonic Corporation
    Inventors: Richard H. Strandberg, Paul Cheng-Po Liang