公开(公告)号：US20240039636A1

公开(公告)日：2024-02-01

申请号：US17875025

申请日：2022-07-27

Applicant: Google LLC

Inventor： Xiang Zhou ,  Cedric F. Lam ,  Hong Liu

IPC: H04B10/556 ,  H04B10/50 ,  H04B10/80

CPC classification number: H04B10/5561 ,  H04B10/5053 ,  H04B10/801

Abstract: Systems and methods are disclosed for two-dimensional optical transmission, including systems and methods for modulating and detecting two-dimensional short-reach optical communications. Two-dimensional optical transmissions may be generated by mapping a first data set to a first dimension of an optical signal and mapping a second data set to a second dimension of an optical signal. The encoded data for the first data set may be combined with the encoded data for the second data set so as to produce drive signals for a dual-drive modulator using a combination of both a common-mode and differential signal. The disclosed systems and methods also include dual-mode optical receivers that are configured to operate in either a one-dimensional or two-dimensional mode.

公开(公告)号：US20220166518A1

公开(公告)日：2022-05-26

申请号：US17665988

申请日：2022-02-07

Applicant: Google LLC

Inventor： Xiang Zhou ,  Hong Liu

IPC: H04B10/556 ,  H04B10/2507 ,  H04B10/524 ,  H04B10/54 ,  H04J14/06

Abstract: A receiver system is provided for receiving a coherent Pulse Amplitude Modulation (PAM) encoded signal. The receiver system may include an optical polarization component configured to modulate a polarization of the received coherent PAM encoded signal. The receiver system may further include a digital signal processor (DSP) configured to perform polarization recovery between the received coherent PAM encoded signal and the LO signal using a first control loop, and to perform phase recovery between the received coherent PAM encoded signal and the LO signal using a second control loop.

公开(公告)号：US11340468B2

公开(公告)日：2022-05-24

申请号：US16985301

申请日：2020-08-05

Applicant: Google LLC

Inventor： Ryohei Urata ,  Lieven Verslegers ,  Hong Liu ,  Daoyi Wang

IPC: G02B27/28 ,  G02B27/09 ,  G02B6/126 ,  G02B6/10 ,  G02B6/27 ,  G02F1/09 ,  G02B5/30 ,  G02B6/42

Abstract: A photonic integrated circulator can be fabricated by including a plurality of polarizing beam splitters and optical polarization rotators such that two copies of the optical signal are output at a receiver in substantially aligned polarization states. The circulator can be used for facilitating bi-directional communications between photonic integrated circuit devices, which are inherently polarization sensitive, while reducing signal loss.

公开(公告)号：US10979148B1

公开(公告)日：2021-04-13

申请号：US16675375

申请日：2019-11-06

Applicant: Google LLC

Inventor： Xiang Zhou ,  Hong Liu

IPC: H04B10/61 ,  H04B10/556 ,  H04B10/54 ,  H04J14/06 ,  H04B10/2507 ,  H04B10/524

Abstract: A receiver system is provided for receiving a coherent Pulse Amplitude Modulation (PAM) encoded signal. The receiver system may include an optical polarization component configured to modulate a polarization of the received coherent PAM encoded signal. The receiver system may further include a digital signal processor (DSP) configured to perform polarization recovery between the received coherent PAM encoded signal and the LO signal using a first control loop, and to perform phase recovery between the received coherent PAM encoded signal and the LO signal using a second control loop.

公开(公告)号：US20200036568A1

公开(公告)日：2020-01-30

申请号：US16594640

申请日：2019-10-07

Applicant: Google LLC

Inventor： Hong Liu ,  Xiang Zhou

IPC: H04L27/38 ,  H04L5/00 ,  H04L27/00 ,  H04B10/079 ,  H04B10/61 ,  H04B10/516 ,  H04L1/00 ,  H04L1/20

Abstract: System for adjusting a reference constellation for demodulating an optical signal include a coherent electro-optical receiver configured to convert a received optical signal to a plurality of electrical signals, an array of analog-to-digital convertors configured to digitize the plurality of electrical signals, and processor logic. The processor logic is configured to process the digitized plurality of electrical signals using a reference constellation to yield a plurality of decoded signals and a signal quality measurement. The reference constellation includes an inphase component equal to an ideal inphase component plus an inphase offset and a quadrature component equal to an ideal quadrature component plus a quadrature offset. The processor logic is configured to determine an optimal inphase offset and optimal quadrature offset. The processor logic is configured to update the reference constellation using the optimal inphase offset and the optimal quadrature offset.

公开(公告)号：US20180316541A1

公开(公告)日：2018-11-01

申请号：US15583862

申请日：2017-05-01

Applicant: Google LLC

Inventor： Hong Liu ,  Xiang Zhou

IPC: H04L27/38 ,  H04B10/61 ,  H04B10/516 ,  H04L1/20 ,  H04L1/00

Abstract: System for adjusting a reference constellation for demodulating an optical signal include a coherent electro-optical receiver configured to convert a received optical signal to a plurality of electrical signals, an array of analog-to-digital convertors configured to digitize the plurality of electrical signals, and processor logic. The processor logic is configured to process the digitized plurality of electrical signals using a reference constellation to yield a plurality of decoded signals and a signal quality measurement. The reference constellation includes an inphase component equal to an ideal inphase component plus an inphase offset and a quadrature component equal to an ideal quadrature component plus a quadrature offset. The processor logic is configured to determine an optimal inphase offset and optimal quadrature offset. The processor logic is configured to update the reference constellation using the optimal inphase offset and the optimal quadrature offset.

公开(公告)号：US20180198533A1

公开(公告)日：2018-07-12

申请号：US15914583

申请日：2018-03-07

Applicant: Google LLC

Inventor： Xiang Zhou ,  Ryohei Urata ,  Erji Mao ,  Hong Liu ,  Christopher Lyle Johnson

IPC: H04B10/69

CPC classification number: H04B10/6971 ,  H04B10/697

Abstract: This disclosure provides systems, methods, and apparatus for mitigating the effects of interference signals on optical signals received at a direct-detection optical receivers. The optical receivers are capable of attenuating interference noise signals resulting from the interference between a transmitted optical signal transmitted from a transmitter to the optical receiver and one or more additional signals received at the optical receiver. The interference can be due to multi-path interference or due to in-band interference. The receivers include a tunable filter for filtering the received optical signal to remove the interference. A frequency offset module processes the received optical signal to determine a frequency offset indicative of the difference between the carrier frequencies of a modulated optical signal and an interference optical signal. The offset frequency and a bandwidth determined by the frequency offset module can be used to adjust the tunable filter to remove the interference signal from the received signal.

公开(公告)号：US12160272B2

公开(公告)日：2024-12-03

申请号：US17848948

申请日：2022-06-24

Applicant: Google LLC

Inventor： Xiang Zhou ,  Cedric F. Lam ,  Hong Liu

IPC: H04B10/61 ,  G02B6/27 ,  G02B6/293 ,  G02B27/28 ,  H04B10/50

Abstract: The proposed technology allows for 1+1 optical protection and may improve coherent module output optical power by 3 dB over similar transmitter (Tx) and receiver (Rx) implementation complexity, as well as allow for integration into existing datacenter formats.

公开(公告)号：US11689292B2

公开(公告)日：2023-06-27

申请号：US17228122

申请日：2021-04-12

Applicant: Google LLC

Inventor： Xiang Zhou ,  Cedric F. Lam ,  Ryohei Urata ,  Hong Liu

IPC: H04B10/60 ,  H04B10/532 ,  H04B10/548 ,  H04B10/61 ,  H04B10/40 ,  H04J14/06

CPC classification number: H04B10/532 ,  H04B10/548 ,  H04B10/40 ,  H04B10/60 ,  H04B10/61 ,  H04B10/614 ,  H04J14/06

Abstract: Coherent optical communications technology for recovery of 1D and 2D formatted optical signals. For example, 1D or 2D formatted signals that travel through fiber optic media may be recovered by separating the light into X- and Y-polarization components, rotating one polarization component (e.g., Y-component) into the polarization space of the other component (e.g., Y-component into the X-polarization space), delaying the rotated component enough to avoid destructive interference and combining the delayed component with the undelayed component to form a folded optical signal, which may then be processed as a X-polarized signal.

公开(公告)号：US20220104342A1

公开(公告)日：2022-03-31

申请号：US17034867

申请日：2020-09-28

Applicant: Google LLC

Inventor： Lieven Verslegers ,  Hong Liu ,  Kevin Yasumura ,  Jill Berger ,  Ryohei Urata

IPC: H05K1/02

Abstract: The present disclosure provides for an example integrated optics assembly. The integrated optics assembly may include an optics mount, a substrate including a heat sink, and a photonic integrated circuit (“PIC”). The optics mount may be adapted to support a light source on a first end of the optics mount. The first end of the optics mount may be coupled to a region of the substrate including the heat sink. The heat sink may remove or dissipate the heat produced by the light source. A second end of the optics mount may be coupled to the PIC such that the optics mount extends between the substrate and the PIC. This may decrease the amount of space the optics mount takes up on the PIC thereby allowing the overall size of the PIC to be decreased. Decreasing the size of the PIC may allow for more PICS per wafer.