Liang Teddy Du

US Patent:

20210167577, Jun 3, 2021

Filed:

May 7, 2019

Appl. No.:

17/057649

Inventors:

- Mountain View CA, US
Cedric Fung Lam - San Carlos CA, US
Xiangjun Zhao - Fremont CA, US
Shuang Yin - Sunnyvale CA, US
Liang Du - Santa Clara CA, US
Changhong Joy Jiang - Dublin CA, US
Adam Edwin Taylor Barratt - Portland OR, US
Claudio Desanti - ountain View CA, US
Muthu Nagarajan - Santa Clara CA, US

Assignee:

Google LLC - Mountain View CA

International Classification:

H01S 5/0625
H01S 5/024
H04B 10/572
H04B 10/50
H04J 14/02

Abstract:

A method () for tuning a tunable laser () includes delivering a bias current (I) to an anode of a distributed Bragg reflector (DBR) section diode (D) disposed on a shared substrate of the tunable 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 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.

US Patent:

20210151952, May 20, 2021

Filed:

May 7, 2019

Appl. No.:

17/057645

Inventors:

- Mountain View CA, US
Cedric Fung Lam - San Carlos CA, US
Shuang Yin - Sunnyvale CA, US
Xiangjun Zhao - Fremont CA, US
Liang Du - Santa Clara CA, US
Changhong Joy Jiang - Dublin CA, US
Adam Edwin Taylor Barratt - Portland OR, US
Claudio Desanti - ountain View CA, US
Muthu Nagarajan - Santa Clara CA, US

Assignee:

Google LLC - Mountain View CA

International Classification:

H01S 5/042
H01S 5/0625
H04B 10/50
H04B 10/54
H04B 10/564
H01S 5/026

Abstract:

A method () of biasing a tunable laser () during burst-on and burst-off states includes receiving a burst mode signal () 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 (I) to an anode of a gain-section diode () disposed on a shared substrate of the tunable laser; and delivering a second bias current (I) to an anode of phase-section diode () 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.

US Patent:

20210083770, Mar 18, 2021

Filed:

Sep 12, 2019

Appl. No.:

16/568759

Inventors:

- Mountain View CA, US
Xiangjun Zhao - Fremont CA, US
Shuang Yin - Sunnyvale CA, US
Muthu Nagarajan - Santa Clara CA, US
Tao Zhang - Mountain View CA, US
Liang Du - Santa Clara CA, US
Adam Edwin Taylor Barratt - Portland OR, US
Changhong Joy Jiang - Dublin CA, US
Claudio Desanti - Mountain View CA, US

Assignee:

Google LLC - Mountain View CA

International Classification:

H04B 10/25
H04B 10/69
H04B 10/50
H04B 10/27

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. Configuring the electrical-multiplexing device to select the corresponding input channel causes the electrical-multiplexing device to transmit the corresponding electrical signal to an electro-optical converter configured to convert the corresponding electrical signal back to the respective optical signal.

US Patent:

20190036302, Jan 31, 2019

Filed:

Oct 1, 2018

Appl. No.:

16/148526

Inventors:

- Mountain View CA, US
Liang Du - Santa Clara CA, US
Xiangjun Zhao - Fremont CA, US
Changhong Joy Jiang - Dublin CA, US
Cedric Fung Lam - San Carlos CA, US
Shuang Yin - Sunnyvale CA, US
Adam Edwin Taylor Barratt - Portland OR, US

Assignee:

Google LLC - Mountain View CA

International Classification:

H01S 5/042
H04J 14/02
H01S 5/068
H04B 10/25
H01S 5/0625

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.

US Patent:

20180175964, Jun 21, 2018

Filed:

Dec 20, 2016

Appl. No.:

15/385798

Inventors:

- Mountain View CA, US
Daoyi Wang - San Jose CA, US
Liang Du - Santa Clara CA, US
Changhong Joy Jiang - Dublin CA, US
Cedric Fung Lam - San Carlos CA, US

Assignee:

Google Inc. - Mountain View CA

International Classification:

H04J 14/02
H04B 10/27
H04Q 11/00

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.

US Patent:

20170317778, Nov 2, 2017

Filed:

Jul 20, 2017

Appl. No.:

15/655307

Inventors:

- Mountain View CA, US
Liang Du - Santa Clara CA, US
Changhong Joy Jiang - Dublin CA, US
Ben Warren Segura - Morgan Hill CA, US
Xiangjun Zhao - Fremont CA, US
Daoyi Wang - San Jose CA, US

Assignee:

Google Inc. - Mountain View CA

International Classification:

H04J 14/02
H04J 14/08
H04J 14/02
H04J 14/02
H04J 14/02
H04J 14/02
H04J 14/02
H04Q 11/00
H04B 10/25

Abstract:

A communication system includes a first multiplexer configured to multiplex a first optical line terminal signal having a first multiplexing group and a second optical line terminal signal having a second multiplexing group into a first multiplexed signal. The communication system includes a second multiplexer configured to demultiplex a second multiplexed signal into a third optical line terminal signal having the first multiplexing group and a fourth optical line terminal signal having the second multiplexing group. Moreover, the communication system includes a third multiplexer optically connected with the first multiplexer and the second multiplexer, the third multiplexer configured to multiplex/demultiplex between a feeder optical signal and the first and second multiplexed signals. The first and second optical line terminal signals include a legacy upstream free spectral range, and the third and fourth optical line terminal signals include a legacy downstream free spectral range.

US Patent:

20170155461, Jun 1, 2017

Filed:

Feb 9, 2017

Appl. No.:

15/428859

Inventors:

- Mountain View CA, US
Chiachi Wang - Union City CA, US
Daoyi Wang - San Jose CA, US
Cedric Fung Lam - San Carlos CA, US
Liang Du - Santa Clara CA, US
Changhong Joy Jiang - Dublin CA, US

Assignee:

Google Inc. - Mountain View CA

International Classification:

H04J 14/02
H04J 14/08

Abstract:

A communication system includes a first optical system and a second optical system optically connected to a clamping laser and a pump laser. The first optical system includes first and second optical splitters. The first optical splitter is configured to receive a clamping laser signal from the clamping laser and split the signal into split clamping laser signals. The second optical splitter is configured to receive a pump laser signal from the pump laser and split signal into split pump laser signals. The second optical system is optically connected to the first optical system and includes amplifier systems. Each amplifier system is configured to receive a multiplexed signal. The second optical system includes first and second combiners optically connected to an erbium-doped fiber. The first combiner is optically connected to the first splitter, and the second combiner is optically connected to the second splitter.