Patents by Inventor Cedric Fung Lam

Cedric Fung Lam 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: 11901696
    Abstract: A method (700) of biasing a tunable laser (310) during burst-on and burst-off states includes receiving a burst mode signal (514) indicative of the burst-on state or the burst-off state and when the burst mode signal is indicative of the burst-on state: delivering a first bias current (IGAIN) to an anode of a gain-section diode (590a) disposed on a shared substrate of the tunable laser; and delivering a second bias current (IPH) to an anode of phase-section diode (590b) disposed on the shared substrate. The second bias current is less than the first bias current. When the burst mode signal transitions to be indicative of the burst-off state, the method also includes delivering the first bias current to the anode of the gain-section diode; and delivering the second bias current to the anode of the phase-section diode wherein the first bias current is less than the second bias current.
    Type: Grant
    Filed: May 7, 2019
    Date of Patent: February 13, 2024
    Assignee: Google LLC
    Inventors: Tao Zhang, Cedric Fung Lam, Shuang Yin, Xiangjun Zhao, Liang Du, Changhong Joy Jiang, Adam Edwin Taylor Barratt, Claudio Desanti, Muthu Nagarajan
  • Patent number: 11600965
    Abstract: A method (900) includes a gain current (IGAIN) to an anode of a gain-section diode (D0) disposed on a shared substrate of a tunable laser (310), delivering a modulation signal to an anode of an Electro-absorption section diode (D2) disposed on the shared substrate of the tunable laser, and receiving a burst mode signal (330) indicative of a burst-on state or a burst-off state. When the burst mode signal is indicative of the burst-off state, the method includes sinking a sink current (ISINK) away from the gain current at the anode of the gain-section diode. When the burst mode signal transitions to be indicative of the burst-on state from the burst-off state, the method includes ceasing the sinking of the sink current away from the gain current and delivering an overshoot current (IOVER) to the anode of the gain-section diode.
    Type: Grant
    Filed: May 6, 2019
    Date of Patent: March 7, 2023
    Assignee: Google LLC
    Inventors: Tao Zhang, Cedric Fung Lam, Shuang Yin, Xiangjun Zhao, Liang Du, Changhong Joy Jiang, Adam Edwin Taylor Barratt, Claudio Desanti, Muthu Nagarajan
  • Patent number: 11594856
    Abstract: A method (900) includes delivering a first bias current (IGAIN) to an anode of gain-section diode (590a) and delivering a second bias current (IPH) to an anode of a phase-section diode (590b). The method also includes receiving a burst mode signal (514) indicative of a burst-on state or a burst-on state, and sinking a first sink current (ISINK) away from the first bias current when the burst mode signal is indicative of the burst-off state. When the burst mode signal transitions to be indicative of the burst-on state from the burst-off state, the method also includes sinking a second sink current away from the second bias current at the anode of the phase-section diode and ceasing the sinking of the first sink current away from the first bias current at the anode of the gain section diode.
    Type: Grant
    Filed: May 7, 2019
    Date of Patent: February 28, 2023
    Assignee: Google LLC
    Inventors: Tao Zhang, Cedric Fung Lam, Shuang Yin, Xiangjun Zhao, Liang Du, Changhong Joy Jiang, Adam Edwin Taylor Barratt, Claudio Desanti, Muthu Nagarajan
  • Publication number: 20220210854
    Abstract: A computer-implemented method when executed by data processing hardware of customer premises equipment installed at an exterior portion of a premises of a user causes the data processing hardware to perform operation. The operations include receiving, via a local area network associated with the user, a first communication from a user device located within an interior of the premises of the user. The operations also include receiving, via a low-power wide area network, a second communication from a low-power device located exterior of the premises of the user. The operations also include transmitting, via a broadband connection using a fixed wireless access network, the first communication and the second communication to a remote server.
    Type: Application
    Filed: December 28, 2021
    Publication date: June 30, 2022
    Applicant: Google LLC
    Inventors: Cedric Fung Lam, Milo Steven Medin
  • Publication number: 20210203130
    Abstract: A method (900) includes delivering a first bias current (IGAIN) to an anode of a gain-section diode (590a) and delivering a second bias current (IPH) to an anode of a phase-section diode (590b). The method also includes receiving a burst mode signal (514) indicative of a burst-on state or a burst-on state, and sinking a first sink current (ISINK) away from the first bias current when the burst mode signal is indicative of the burst-off state. When the burst mode signal transitions to be indicative of the burst-on state from the burst-off state, the method also includes sinking a second sink current away from the second bias current at the anode of the phase-section diode and ceasing the sinking of the first sink current away from the first bias current at the anode of the gain section diode.
    Type: Application
    Filed: May 7, 2019
    Publication date: July 1, 2021
    Applicant: Google LLC
    Inventors: Tao Zhang, Cedric Fung Lam, Shuang Yin, Xiangjun Zhao, Liang Du, Changhong Joy Jiang, Adam Edwin Taylor Barratt, Claudio Desanti, Muthu Nagarajan
  • Publication number: 20210203129
    Abstract: A method (900) includes a gain current (IGAIN) to an anode of a gain-section diode (D0) disposed on a shared substrate of a tunable laser (310), delivering a modulation signal to an anode of an Electro-absorption section diode (D2) disposed on the shared substrate of the tunable laser, and receiving a burst mode signal (330) indicative of a burst-on state or a burst-off state. When the burst mode signal is indicative of the burst-off state, the method includes sinking a sink current (ISINK) away from the gain current at the anode of the gain-section diode. When the burst mode signal transitions to be indicative of the burst-on state from the burst-off state, the method includes ceasing the sinking of the sink current away from the gain current and delivering an overshoot current (IOVER) to the anode of the gain-section diode.
    Type: Application
    Filed: May 6, 2019
    Publication date: July 1, 2021
    Applicant: Google LLC
    Inventors: Tao Zhang, Cedric Fung Lam, Shuang Yin, Xiangjun Zhao, Liang Du, Changhong Joy Jiang, Adam Edwin Taylor Barratt, Claudio Desanti, Muthu Nagarajan
  • Publication number: 20210167577
    Abstract: A method (600) for tuning a tunable laser (310) includes delivering a bias current (IDBR) to an anode of a distributed Bragg reflector (DBR) section diode (D2) disposed on a shared substrate of the tunable laser and receiving a burst mode signal (440) indicative of a burst-on state or a burst-off state. When the burst mode signal is indicative of the burst-off state, the method includes offsetting the bias current at the anode of the DBR section diode by one of sourcing a push current with the bias current to the anode of the DBR section diode or sinking a pull current away from the bias current at the anode of the DBR section diode. When the burst mode signal is indicative of the burst-on state, the method also includes ceasing any offsetting of the bias current at the anode of the DBR section diode.
    Type: Application
    Filed: May 7, 2019
    Publication date: June 3, 2021
    Applicant: Google LLC
    Inventors: Tao Zhang, Cedric Fung Lam, Xiangjun Zhao, Shuang Yin, Liang Du, Changhong Joy Jiang, Adam Edwin Taylor Barratt, Claudio Desanti, Muthu Nagarajan
  • Publication number: 20210151952
    Abstract: A method (700) of biasing a tunable laser (310) during burst-on and burst-off states includes receiving a burst mode signal (514) indicative of the burst-on state or the burst-off state and when the burst mode signal is indicative of the burst-on state: delivering a first bias current (IGAIN) to an anode of a gain-section diode (590a) disposed on a shared substrate of the tunable laser; and delivering a second bias current (IPH) to an anode of phase-section diode (590b) disposed on the shared substrate. The second bias current is less than the first bias current. When the burst mode signal transitions to be indicative of the burst-off state, the method also includes delivering the first bias current to the anode of the gain-section diode; and delivering the second bias current to the anode of the phase-section diode wherein the first bias current is less than the second bias current.
    Type: Application
    Filed: May 7, 2019
    Publication date: May 20, 2021
    Applicant: Google LLC
    Inventors: Tao Zhang, Cedric Fung Lam, Shuang Yin, Xiangjun Zhao, Liang Du, Changhong Joy Jiang, Adam Edwin Taylor Barratt, Claudio Desanti, Muthu Nagarajan
  • Patent number: 10992387
    Abstract: A method of combining optical signals from a plurality of optical fibers into a single optical signal includes receiving, at corresponding optical-signal receivers optically coupled to corresponding trunk fibers, respective optical signals. The method further includes determining, by the corresponding optical-signal receivers, when each respective optical signal is received. When the respective optical signal is received, the method includes performing the following steps: converting, by the corresponding optical-signal receiver, the respective optical signal to a corresponding electrical signal; transmitting, by the corresponding optical-signal receiver, the corresponding electrical signal to a corresponding input channel of an electrical-multiplexing device; and configuring the electrical-multiplexing device to select the corresponding input channel.
    Type: Grant
    Filed: September 12, 2019
    Date of Patent: April 27, 2021
    Assignee: Google LLC
    Inventors: Cedric Fung Lam, Xiangjun Zhao, Shuang Yin, Muthu Nagarajan, Tao Zhang, Liang Du, Adam Edwin Taylor Barratt, Changhong Joy Jiang, Claudio Desanti
  • Publication number: 20210083770
    Abstract: A method of combining optical signals from a plurality of optical fibers into a single optical signal includes receiving, at corresponding optical-signal receivers optically coupled to corresponding trunk fibers, respective optical signals. The method further includes determining, by the corresponding optical-signal receivers, when each respective optical signal is received. When the respective optical signal is received, the method includes performing the following steps: converting, by the corresponding optical-signal receiver, the respective optical signal to a corresponding electrical signal; transmitting, by the corresponding optical-signal receiver, the corresponding electrical signal to a corresponding input channel of an electrical-multiplexing device; and configuring the electrical-multiplexing device to select the corresponding input channel.
    Type: Application
    Filed: September 12, 2019
    Publication date: March 18, 2021
    Applicant: Google LLC
    Inventors: Cedric Fung Lam, Xiangjun Zhao, Shuang Yin, Muthu Nagarajan, Tao Zhang, Liang Du, Adam Edwin Taylor Barratt, Changhong Joy Jiang, Claudio Desanti
  • Patent number: 10666379
    Abstract: A method of establishing communication between an optical line terminal and an optical network unit within an optical access network includes receiving a signal indication from an optical transceiver of an optical line terminal. The signal indication includes: (i) a loss-of-signal indication indicating non-receipt of an upstream optical signal from the optical network unit; or (ii) a signal-received indication indicating receipt of the upstream optical signal from the optical network unit. The method includes determining whether the signal indication includes the loss-of-signal indication. When the signal indication includes the loss-of-signal indication, the method includes instructing the optical transceiver to cease signal transmission from the optical transceiver to the optical network unit.
    Type: Grant
    Filed: March 13, 2019
    Date of Patent: May 26, 2020
    Assignee: Google LLC
    Inventors: Xiangjun Zhao, Cedric Fung Lam, Shuang Yin, Changhong Joy Jiang, Ke Dong
  • Patent number: 10651946
    Abstract: A method for in-field calibration of a laser transmitter includes receiving, at an optical network unit (ONU), a downstream connection from an optical line terminal (OLT) where the ONU includes a Distributed Bragg Reflector (DBR) laser. The method further includes attempting to establish an upstream connection between the ONU and the OLT. When the ONU establishes the upstream connection to the OLT, the method also includes receiving, at the ONU, a message to initiate calibration of the ONU where the message is generated to indicate that the DBR laser is operating outside an operational state. The method further includes tuning, by the ONU, the DBR laser to the operational state by adjusting an injection current for the DBR laser.
    Type: Grant
    Filed: May 30, 2019
    Date of Patent: May 12, 2020
    Assignee: Google LLC
    Inventors: Xiangjun Zhao, Satrukaan Sivagnanasuntharam, Shuang Yin, Cedric Fung Lam, Liang Du
  • Publication number: 20190393958
    Abstract: A remote node includes a first node input, a second node input, and an optical switch. The optical switch includes a first switch input optically coupled to the first node input, a second switch input optically coupled to the second node input, a first switch output switchably coupled to the first switch input or the second switch input, and a second switch output switchably coupled to the first switch input or the second switch input. The remote node includes a photodiode optically coupled to the second switch output, and a capacitor electrically coupled to the photodiode and the optical switch. When the first switch input is switchably coupled to the first switch output, the second switch input is switchably coupled to the second switch output. Light received by the second switch input passes out the second switch output to the photodiode. The photodiode charges the capacitor to a threshold charge.
    Type: Application
    Filed: August 28, 2019
    Publication date: December 26, 2019
    Applicant: Google LLC
    Inventors: Liang Du, Yut Loy Chan, Xiangjun Zhao, Changhong Joy Jiang, Cedric Fung Lam, Daoyi Wang, Tao Zhang
  • Patent number: 10516479
    Abstract: A remote node includes a first node input, a second node input, and an optical switch. The optical switch includes a first switch input optically coupled to the first node input, a second switch input optically coupled to the second node input, a first switch output switchably coupled to the first switch input or the second switch input, and a second switch output switchably coupled to the first switch input or the second switch input. The remote node includes a photodiode optically coupled to the second switch output, and a capacitor electrically coupled to the photodiode and the optical switch. When the first switch input is switchably coupled to the first switch output, the second switch input is switchably coupled to the second switch output. Light received by the second switch input passes out the second switch output to the photodiode. The photodiode charges the capacitor to a threshold charge.
    Type: Grant
    Filed: August 28, 2019
    Date of Patent: December 24, 2019
    Assignee: Google LLC
    Inventors: Liang Du, Yut Loy Chan, Xiangjun Zhao, Changhong Joy Jiang, Cedric Fung Lam, Daoyi Wang, Tao Zhang
  • Patent number: 10461498
    Abstract: A method for biasing a tunable laser during burst-on and burst-off states through a common-cathode laser driving circuit includes delivering a bias current to an anode of a gain-section diode having a shared substrate with the laser, and receiving a burst mode signal indicative of a burst-on state or a burst-off state. When the burst mode signal is indicative of the burst-off state, the method includes sinking a sink current away from the anode of the gain-section diode. The sink current is less than the bias current delivered to the anode of the gain-section diode. When the burst mode signal transitions to be indicative of the burst-on state from the burst-off state, the method includes ceasing the sinking of the sink current away from the anode of the gain-section diode, and delivering an overshoot current to the anode of the gain-section diode to accelerate heating of the gain-section diode.
    Type: Grant
    Filed: October 1, 2018
    Date of Patent: October 29, 2019
    Assignee: Google LLC
    Inventors: Tao Zhang, Liang Du, Xiangjun Zhao, Changhong Joy Jiang, Cedric Fung Lam, Shuang Yin, Adam Edwin Taylor Barratt
  • Patent number: 10439722
    Abstract: A carrier office includes an optical line terminal, a first transmit-erbium-doped fiber amplifier (EDFA), and a second transmit-EDFA. The OLT is configured to transmit first and second optical signals. The first transmit-EDFA is optically coupled to the OLT and a first feeder fiber, and the first feeder fiber is optically coupled to a first remote node (RN). The first transmit-EDFA is operable between a respective enabled state and a respective disabled state. The second transmit-EDFA is optically coupled to the OLT and a second feeder fiber, and the second feeder fiber is optically coupled to a second RN. The second transmit-EDFA is operable between a respective enabled state and a respective disabled state.
    Type: Grant
    Filed: July 17, 2018
    Date of Patent: October 8, 2019
    Assignee: Google LLC
    Inventors: Liang Du, Yut Loy Chan, Xiangjun Zhao, Changhong Joy Jiang, Cedric Fung Lam, Daoyi Wang, Tao Zhang
  • Publication number: 20190215093
    Abstract: A method of establishing communication between an optical line terminal and an optical network unit within an optical access network includes receiving a signal indication from an optical transceiver of an optical line terminal. The signal indication includes: (i) a loss-of-signal indication indicating non-receipt of an upstream optical signal from the optical network unit; or (ii) a signal-received indication indicating receipt of the upstream optical signal from the optical network unit. The method includes determining whether the signal indication includes the loss-of-signal indication. When the signal indication includes the loss-of-signal indication, the method includes instructing the optical transceiver to cease signal transmission from the optical transceiver to the optical network unit.
    Type: Application
    Filed: March 13, 2019
    Publication date: July 11, 2019
    Applicant: Google LLC
    Inventors: Xiangjun Zhao, Cedric Fung Lam, Shuang Yin, Changhong Joy Jiang, Ke Dong
  • Patent number: 10243687
    Abstract: A method of establishing communication between an optical line terminal and an optical network unit within an optical access network includes receiving a signal indication from an optical transceiver of an optical line terminal. The signal indication includes: (i) a loss-of-signal indication indicating non-receipt of an upstream optical signal from the optical network unit; or (ii) a signal-received indication indicating receipt of the upstream optical signal from the optical network unit. The method includes determining whether the signal indication includes the loss-of-signal indication. When the signal indication includes the loss-of-signal indication, the method includes instructing the optical transceiver to cease signal transmission from the optical transceiver to the optical network unit.
    Type: Grant
    Filed: November 17, 2016
    Date of Patent: March 26, 2019
    Assignee: Google LLC
    Inventors: Xiangjun Zhao, Cedric Fung Lam, Shuang Yin, Changhong Joy Jiang, Ke Dong
  • Publication number: 20190036302
    Abstract: A method for biasing a tunable laser during burst-on and burst-off states through a common-cathode laser driving circuit includes delivering a bias current to an anode of a gain-section diode having a shared substrate with the laser, and receiving a burst mode signal indicative of a burst-on state or a burst-off state. When the burst mode signal is indicative of the burst-off state, the method includes sinking a sink current away from the anode of the gain-section diode. The sink current is less than the bias current delivered to the anode of the gain-section diode. When the burst mode signal transitions to be indicative of the burst-on state from the burst-off state, the method includes ceasing the sinking of the sink current away from the anode of the gain-section diode, and delivering an overshoot current to the anode of the gain-section diode to accelerate heating of the gain-section diode.
    Type: Application
    Filed: October 1, 2018
    Publication date: January 31, 2019
    Applicant: Google LLC
    Inventors: Tao Zhang, Liang Du, Xiangjun Zhao, Changhong Joy Jiang, Cedric Fung Lam, Shuang Yin, Adam Edwin Taylor Barratt
  • Patent number: 10171199
    Abstract: A system includes a multiplexer having a pass-band and an optical network unit (ONU) optically coupled to the multiplexer. The ONU includes a tunable laser configured to continuously transmit an optical signal to the multiplexer in a burst-on state and a burst-off state. While in the burst-on state, the ONU is configured to tune the tunable laser to transmit the optical signal at a transmit wavelength within the wavelength pass-band of the multiplexer. The multiplexer configured to allow passage therethrough of the optical signal at the transmit wavelength. While in the burst-off state, the ONU is configured to tune the tunable laser to transmit the optical signal at a non-transmit wavelength outside of the wavelength pass-band of the multiplexer. The multiplexer configured to block passage therethrough of the optical signal at the non-transmit wavelength.
    Type: Grant
    Filed: December 20, 2016
    Date of Patent: January 1, 2019
    Assignee: Google LLC
    Inventors: Xiangjun Zhao, Daoyi Wang, Liang Du, Changhong Joy Jiang, Cedric Fung Lam