Patents by Inventor Lai Kan Leung

Lai Kan Leung 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: 10305517
    Abstract: An apparatus is disclosed for current-mode filtering with switching. In an example aspect, the apparatus includes a filter including two input nodes, two output nodes, two differential paths, two bypass nodes respectively coupled between the two input nodes and the two output nodes along the two differential paths, a high-pass filter coupled between the two bypass nodes and the two output nodes, two low-pass switches, a band-pass switch, and a low-pass filter coupled in series with the high-pass filter along the two differential paths. The high-pass filter includes two series capacitors, which are respectively coupled between the two bypass nodes and the two output nodes, and two shunt inductors, which are respectively coupled to the two bypass nodes. The two low-pass switches are respectively coupled in parallel with the two series capacitors. The band-pass switch is coupled in series between the two shunt inductors.
    Type: Grant
    Filed: July 5, 2018
    Date of Patent: May 28, 2019
    Assignee: QUALCOMM Incorporated
    Inventors: Timothy Donald Gathman, Chirag Dipak Patel, Lai Kan Leung
  • Patent number: 10250314
    Abstract: Certain aspects of the present disclosure provide multi-way diversity receivers with multiple synthesizers. Such a multi-way diversity receiver may be implemented in a carrier aggregation (CA) transceiver. One example wireless reception diversity circuit generally includes three or more receive paths for processing received signals and two or more frequency synthesizing circuits configured to generate local oscillating signals to downconvert the received signals. Each of the frequency synthesizing circuits is shared by at most two of the receive paths, and each pair of the frequency synthesizing circuits may generate a pair of local oscillating signals having the same frequency.
    Type: Grant
    Filed: June 29, 2017
    Date of Patent: April 2, 2019
    Assignee: QUALCOMM Incorporated
    Inventors: Lai Kan Leung, Chiewcharn Narathong, Rajagopalan Rangarajan, Dongling Pan, Yiwu Tang, Aleksandar Miodrag Tasic
  • Publication number: 20190097608
    Abstract: Certain aspects of the present disclosure relate to multi-band filter architectures and methods for filtering signals using the multi-band filter architectures. One example multi-band filter generally includes a transconductance-capacitance (gm-C) filter and a reconfigurable load impedance coupled to an output of the gm-C filter, the reconfigurable load impedance comprising a first gyrator circuit coupled to a second gyrator circuit.
    Type: Application
    Filed: September 22, 2017
    Publication date: March 28, 2019
    Inventors: Timothy Donald GATHMAN, Lai Kan LEUNG, Chirag Dipak PATEL, Rajagopalan RANGARAJAN
  • Patent number: 10193580
    Abstract: Devices and techniques are described to extract specific frequency band signals from a wide-band radio-frequency signal. A network entity may include an antenna for receiving the wide-band radio-frequency signal and may include a receiver circuit for processing the wide-band radio-frequency signal. The receiver circuit may include a transconductance amplifier and a plurality of single-band circuits. The transconductance amplifier may be configured to generate an amplified wide-band radio-frequency signal and send it to one or more of the single-band circuits. Each single-band circuit may be configured to extract a different frequency band signal from the amplified wide-band radio-frequency signal.
    Type: Grant
    Filed: March 20, 2018
    Date of Patent: January 29, 2019
    Assignee: QUALCOMM Incorporated
    Inventors: Chirag Dipak Patel, Lai Kan Leung, Xinmin Yu, Timothy Donald Gathman, Ravi Sridhara
  • Patent number: 10193497
    Abstract: Methods, systems, and devices for wireless communication are described for enhanced broadband operation of an active mixer. In an example, an apparatus may include an active mixer that converts between radio frequency (RF) signals and intermediate frequency (IF) signals based at least in part on an alternating current (AC) local oscillator (LO) signal, wherein a direct current (DC) current generated within the active mixer is dependent in part on a bias voltage and the AC LO signal. The apparatus may include a mixer biasing circuit that generates the bias voltage for the active mixer, a magnitude of the bias voltage having an inverse relationship to an amplitude of the AC LO signal.
    Type: Grant
    Filed: December 4, 2017
    Date of Patent: January 29, 2019
    Assignee: QUALCOMM Incorporated
    Inventors: Xinmin Yu, Timothy Donald Gathman, Lai Kan Leung
  • Patent number: 10153934
    Abstract: In certain aspects, a circuit comprises a low noise amplifier (LNA) configured to receive a radio frequency (RF) signal, a first mixer coupled to the low noise amplifier (LNA), and a first trans-impedance filter coupled to the first mixer. The first trans-impedance filter comprises a tunable inductor and capacitor (LC) network configured to be a portion of a doubly terminated LC ladder filter and a trans-impedance amplifier (TIA) coupled to the tunable inductor and capacitor (LC) network. The circuit further comprises a second mixer coupled to the low noise amplifier (LNA) and a second trans-impedance filter coupled to the second mixer.
    Type: Grant
    Filed: October 11, 2017
    Date of Patent: December 11, 2018
    Assignee: QUALCOMM Incorporated
    Inventors: Timothy Donald Gathman, Chirag Dipak Patel, Lai Kan Leung, Xinmin Yu, Rajagopalan Rangarajan
  • Publication number: 20180278277
    Abstract: Devices and techniques are described to extract specific frequency band signals from a wide-band radio-frequency signal. A network entity may include an antenna for receiving the wide-band radio-frequency signal and may include a receiver circuit for processing the wide-band radio-frequency signal. The receiver circuit may include a transconductance amplifier and a plurality of single-band circuits. The transconductance amplifier may be configured to generate an amplified wide-band radio-frequency signal and send it to one or more of the single-band circuits. Each single-band circuit may be configured to extract a different frequency band signal from the amplified wide-band radio-frequency signal.
    Type: Application
    Filed: March 20, 2018
    Publication date: September 27, 2018
    Inventors: Chirag Dipak Patel, Lai Kan Leung, Xinmin Yu, Timothy Donald Gathman, Ravi Sridhara
  • Publication number: 20180205413
    Abstract: Various aspects described herein relate to low-loss multi-band multiplexing schemes for a wireless communications system, for example, a 5th Generation (5G) New Radio (NR) system. In an aspect, a multiplexer for multi-band wireless communications comprises at least one tuning component configured to transmit or receive at least one signal within a frequency band that is selected from a plurality of frequency bands. The multiplexer further comprises at least one combining component, communicatively coupled with the at least one tuning component, configured to transmit or receive the at least one signal within the selected frequency band. In an aspect, the at least one tuning component is integrated on a chip and the at least one combining component is not integrated on the chip.
    Type: Application
    Filed: January 16, 2018
    Publication date: July 19, 2018
    Inventors: Chirag Dipak PATEL, Lai Kan LEUNG, Zhang JIN, Chinmaya MISHRA, Ravi SRIDHARA, Youngchang YOON
  • Publication number: 20180159474
    Abstract: Methods, systems, and devices for wireless communication are described for enhanced broadband operation of an active mixer. In an example, an apparatus may include an active mixer that converts between radio frequency (RF) signals and intermediate frequency (IF) signals based at least in part on an alternating current (AC) local oscillator (LO) signal, wherein a direct current (DC) current generated within the active mixer is dependent in part on a bias voltage and the AC LO signal. The apparatus may include a mixer biasing circuit that generates the bias voltage for the active mixer, a magnitude of the bias voltage having an inverse relationship to an amplitude of the AC LO signal.
    Type: Application
    Filed: December 4, 2017
    Publication date: June 7, 2018
    Inventors: Xinmin Yu, Timothy Donald Gathman, Lai Kan Leung
  • Patent number: 9985618
    Abstract: An apparatus includes a phase detector coupled to an output of a frequency multiplier. A digital loop filter is coupled to the phase detector, and a duty cycle correction circuit is coupled to the digital loop filter.
    Type: Grant
    Filed: May 12, 2016
    Date of Patent: May 29, 2018
    Assignee: QUALCOMM Incorporated
    Inventors: Dongmin Park, Jong Min Park, Lai Kan Leung
  • Publication number: 20180138822
    Abstract: A method and system for self-powering a clock input buffer is disclosed. The system includes an input node adapted to receive an alternating current (AC) signal having an instantaneous voltage oscillating between a minimum voltage and a maximum voltage. The system includes a pass transistor having a voltage controlled terminal, a first transfer terminal, and a second transfer terminal. The first transfer terminal connects to the input node and the second transfer terminal connects to a power node. The circuit also includes a plurality of transistors adapted to form a logic gate connected to the power node, and having a sensing terminal connected to the input node and an output terminal connected to the voltage controlled terminal. The logic gate produces a control voltage on the output terminal in response to an input voltage on the sensing terminal. The circuit also includes an energy-storage element having a first terminal connected to the power node.
    Type: Application
    Filed: November 11, 2016
    Publication date: May 17, 2018
    Inventors: Dongmin Park, Jong Min Park, Lai Kan Leung
  • Publication number: 20180062655
    Abstract: A level-shifter is provided in which the devices may all be sized approximately the same yet a known startup state is provided at power-up by forming the level-shifter using a one-sided NMOS latch. The one-sided NMOS latch is powered through a pair of head-switch transistors. A pair of pull-down transistors function to flip a binary state for the one-sided NMOS latch.
    Type: Application
    Filed: August 31, 2016
    Publication date: March 1, 2018
    Inventors: Dongmin Park, Jong Min Park, Lai Kan Leung
  • Publication number: 20180013600
    Abstract: An apparatus includes a low noise amplifier (LNA) multiplexer configured to receive a plurality of radio frequency (RF) signals at a plurality of input terminals and to combine the plurality of RF signals into a combined RF signal that is output at an output terminal. The LNA multiplexer includes a plurality of input signal paths, and each input signal path is coupleable to a respective input terminal of the plurality of input terminals and is configured to receive a respective RF signal of the plurality of RF signals. The apparatus further includes an LNA demultiplexer configured to receive the combined RF signal at an input port coupled to the output terminal and to distribute the combined RF signal to a plurality of output ports, each output port of the plurality of output ports configured to output the combined RF signal to a respective downconverter of a plurality of downconverters.
    Type: Application
    Filed: September 25, 2017
    Publication date: January 11, 2018
    Inventors: Aleksandar Miodrag Tasic, Chiewcharn Narathong, Christian Holenstein, Dongling Pan, Yiwu Tang, Rajagopalan Rangarajan, Lai Kan Leung
  • Publication number: 20170302358
    Abstract: Certain aspects of the present disclosure provide multi-way diversity receivers with multiple synthesizers. Such a multi-way diversity receiver may be implemented in a carrier aggregation (CA) transceiver. One example wireless reception diversity circuit generally includes three or more receive paths for processing received signals and two or more frequency synthesizing circuits configured to generate local oscillating signals to downconvert the received signals. Each of the frequency synthesizing circuits is shared by at most two of the receive paths, and each pair of the frequency synthesizing circuits may generate a pair of local oscillating signals having the same frequency.
    Type: Application
    Filed: June 29, 2017
    Publication date: October 19, 2017
    Inventors: Lai Kan LEUNG, Chiewcharn NARATHONG, Rajagopalan RANGARAJAN, Dongling PAN, Yiwu TANG, Aleksandar Miodrag TASIC
  • Patent number: 9774485
    Abstract: Multiplex modules for use in carrier aggregation receivers are disclosed. In an exemplary embodiment, an apparatus includes an LNA multiplexer configured to receive a plurality of RF signals at a plurality of input terminals and to combine the RF signals into a combined RF signal that is output from an output terminal. The apparatus also includes an LNA demultiplexer configured to receive the combined RF signal at an input port that is connected to the output terminal and to distribute the combined RF signal to a plurality of output ports.
    Type: Grant
    Filed: March 20, 2015
    Date of Patent: September 26, 2017
    Assignee: QUALCOMM Incorporated
    Inventors: Aleksandar Miodrag Tasic, Chiewcharn Narathong, Christian Holenstein, Dongling Pan, Yiwu Tang, Rajagopalan Rangarajan, Lai Kan Leung
  • Patent number: 9712226
    Abstract: Certain aspects of the present disclosure provide multi-way diversity receivers with multiple synthesizers. Such a multi-way diversity receiver may be implemented in a carrier aggregation (CA) transceiver. One example wireless reception diversity circuit generally includes three or more receive paths for processing received signals and two or more frequency synthesizing circuits configured to generate local oscillating signals to downconvert the received signals. Each of the frequency synthesizing circuits is shared by at most two of the receive paths, and each pair of the frequency synthesizing circuits may generate a pair of local oscillating signals having the same frequency.
    Type: Grant
    Filed: April 2, 2015
    Date of Patent: July 18, 2017
    Assignee: QUALCOMM Incorporated
    Inventors: Lai Kan Leung, Chiewcharn Narathong, Rajagopalan Rangarajan, Dongling Pan, Yiwu Tang, Aleksandar Miodrag Tasic
  • Publication number: 20170187364
    Abstract: An apparatus includes a phase detector coupled to an output of a frequency multiplier. A digital loop filter is coupled to the phase detector, and a duty cycle correction circuit is coupled to the digital loop filter.
    Type: Application
    Filed: May 12, 2016
    Publication date: June 29, 2017
    Inventors: Dongmin Park, Jong Min Park, Lai Kan Leung
  • Patent number: 9681447
    Abstract: Certain aspects of the present disclosure provide methods and apparatus for dynamically adjusting a voltage-controlled oscillator (VCO) frequency, a local oscillator (LO) divider ratio, and/or a receive path when adding or discontinuing reception of a component carrier (CC) in a carrier aggregation (CA) scheme. This dynamic adjustment is utilized to avoid (or at least reduce) VCO, LO, and transmit signal coupling issues with multiple component carriers, with minimal (or at least reduced) current consumption by the VCO and the LO divider.
    Type: Grant
    Filed: March 3, 2015
    Date of Patent: June 13, 2017
    Assignee: QUALCOMM Incorporated
    Inventors: Yiwu Tang, Rajagopalan Rangarajan, Chiewcharn Narathong, Lai Kan Leung, Aleksandar Miodrag Tasic, Dongling Pan
  • Patent number: 9615369
    Abstract: Methods and apparatus including: setting up a plurality of configurations for a plurality of local oscillator (LO) paths of a carrier aggregation (CA) transceiver operating with a plurality of bands; calculating and comparing frequencies for each LO path of the plurality of LO paths and at least one divider ratio of LO dividers for each band of the plurality of bands to identify frequency conflicts; and reconfiguring the LO dividers for the plurality of LO paths and the plurality of bands when the frequency conflicts are identified.
    Type: Grant
    Filed: March 11, 2015
    Date of Patent: April 4, 2017
    Assignee: QUALCOMM INCORPORATED
    Inventors: Rajagopalan Rangarajan, Chiewcharn Narathong, Lai Kan Leung, Dongling Pan, Aleksandar Miodrag Tasic, Yiwu Tang
  • Publication number: 20170094641
    Abstract: An apparatus comprising a transmit path, a plurality of local oscillators and a control unit. The control unit may be configured to: receive an upcoming resource block (RB) allocation; determine whether the upcoming RB allocation is the same as the current RB allocation; in response to determining that the upcoming RB allocation is different than the current RB allocation: select an unused LO of the plurality of LOs; determine whether a number of allocated RBs associated with the upcoming RB allocation is greater than a threshold; and in response to determining that the number of allocated RBs associated with the upcoming RB allocation is not greater than the threshold, tune the selected LO to a frequency corresponding to the upcoming RB allocation.
    Type: Application
    Filed: April 1, 2016
    Publication date: March 30, 2017
    Inventors: Bhushan Shanti Asuri, Jingcheng Zhuang, Praveen Sampath, Shrenik Patel, Jeremy Darren Dunworth, Lai Kan Leung, Gurkanwal Singh Sahota, Jong Min Park