Methods and apparatus for high-speed coherent optical interconnects

Patent metadata

Field	Value
Publication number	US-2023254048-A1
Application number	US-202318165668-A
Country	US
Kind code	A1
Filing date	Feb 7, 2023
Priority date	Feb 7, 2022
Publication date	Aug 10, 2023
Grant date	—

Abstract

Present disclosure provides a self-homodyne coherent (SHC) system (100) for high-speed coherent optical interconnects, the SHC (100) comprises a first transceiver (101a) and a second transceiver (101b), each of the first transceiver (101a) and one second transceiver (101b) comprises adaptive polarization controller (401), a multi-core fiber link (103) connecting first transceiver (101a) to second transceiver (101b), the first transceiver (101a) is connected to first core for forward transmission of a first signal to the second transceiver (101b), and the first transceiver (101a) is connected to second core for backward transmission of a second signal from the second transceiver (101b), and adaptive polarization controller (401) of the first transceiver (101a) and the second transceiver (101b) is configured to control a coupled optical signal polarization associated with the first signal received at second transceiver (101b) and control a coupled optical signal polarization associated with second signal received at first transceiver (101a)..

First claim

We claim:

1 . A self-homodyne coherent (SHC) system ( 100 ) for high-speed coherent optical interconnects, wherein the SHC ( 100 ) system comprises:
at least one first transceiver ( 101 a ) and at least one second transceiver ( 101 b ) of a plurality of transceivers ( 101 a -N), wherein each of the at least one first transceiver ( 101 a ) and the at least one second transceiver ( 101 b ) comprises at least one adaptive polarization controller ( 401 ); a multi-core fiber link ( 103 ) connecting the at least one first transceiver ( 101 a ) to the at least one second transceiver ( 101 b ) of the plurality of transceivers ( 101 a -N); wherein the at least one first transceiver ( 101 a ) is connected to at least one first core for forward transmission of a first signal to the at least one second transceiver ( 101 b ) respectively, and wherein the at least one first transceiver ( 101 a ) is connected to at least one second core for backward transmission of a second signal from the at least one second transceiver ( 101 b ) respectively, and wherein the at least one adaptive polarization controller ( 401 ) of each of the at least one first transceiver ( 101 a ) and the at least one second transceiver ( 101 b ) is configured to adaptively control a coupled optical signal polarization associated with the first signal received at the at least one second transceiver ( 101 b ) and adaptively control a coupled optical signal polarization associated with the second signal received at the at least one first transceiver ( 101 a ).

2 . The SHC system as claimed in claim 1 , wherein the first signal and the second signal are a coherent modulated signals with carriers in orthogonal polarization propagating bi-directionally.

3 . The SHC system as claimed in claim 2 , wherein the carrier in the orthogonal polarization and the coherent modulated signal is separated by the at least one adaptive polarization controller ( 401 ) of each of the at least one first transceiver ( 101 a ) and the at least one second transceiver ( 101 b ) during receiving the first signal.

4 . The SHC system as claimed in claim 2 , wherein the carrier in the orthogonal polarization and the coherent modulated signal is separated by the at least one adaptive polarization controller ( 401 ) of each of the at least one first transceiver ( 101 a ) and the at least one second transceiver ( 101 b ) during receiving the second signal.

5 . The SHC system as claimed in claim 1 , wherein the first signal comprises a plurality of wavelengths.

6 . The SHC system as claimed in claim 1 , wherein the at least one second transceiver ( 101 b ) comprises:
at least one wavelength division multiplexer ( 104 b ) configured to multiplex the plurality of wavelengths received from the at least one first transceiver ( 101 a ).

7 . The SHC system as claimed in claim 1 , wherein the at least one first transceiver ( 101 a ) comprises:
at least one wavelength division multiplexer ( 104 a ) configured to multiplex the plurality of wavelengths received from the at least one second transceiver ( 101 b ).

8 . The SHC system as claimed in claim 1 , wherein adjacent cores of the multi-core fiber link ( 103 ) configured to carry signals of non-overlapping wavelengths of the plurality of wavelengths.

9 . The SHC system as claimed in claim 1 , wherein adjacent cores of the multi-core fiber link ( 103 ) configured to carry the signals in opposite direction.

10 . The SHC system as claimed in claim 1 , wherein the at least one adaptive polarization controller ( 401 ) of the at least one second transceiver ( 101 b ) is configured to:
receive the first signal; split the first signal into corresponding dual polarization signals; determine a difference in power between the dual polarization signals of the first signal; and equalize the dual polarization signals of the first signal based on a feedback parameter, wherein the feedback parameter is determined based on signal processing technique.

11 . The SHC system as claimed in claim 1 , wherein the at least one adaptive polarization controller ( 401 ) of the at least one first transceiver ( 101 a ) is configured to:
receive the second signal; split the second signal into corresponding dual polarization signals; determine a difference in power between the dual polarization signals of the second signal; and equalize the dual polarization signals of the second signal based on a feedback parameter, wherein the feedback parameter is determined based on signal processing technique.

12 . An adaptive polarization controller ( 401 ) configured to:
receive at least one signal; split the at least one signal into corresponding dual polarization signals; determine a difference in power between the dual polarization signals of the at least one signal; and equalize the dual polarization signals of the signal based on a feedback parameter, wherein the feedback parameter is determined based on signal processing technique.

13 . The adaptive polarization controller ( 401 ) as claimed in claim 12 , wherein the adaptive polarization controller ( 401 ) comprises:
a coupler ( 402 ) configured to split the at least one received signal into corresponding dual polarization signals: at least one multiplexer ( 406 a ) configured to multiplex the dual polarization signals; at least one attenuator ( 403 a ) configured to adaptively control a coupled optical power associated with the at least one signal based on the feedback parameter.

14 . The adaptive polarization controller ( 401 ) as claimed in claim 12 , wherein the adaptive polarization controller ( 401 ) comprises:
a control signal generator ( 404 ) configured to determine the feedback parameter based on the polarization dependent crosstalk between the dual polarization signals of the at least one signal; and a control unit ( 405 ) configured to provide the feedback parameter to the at least one attenuator ( 403 a ).

Assignees

• Indian Inst Technology Bombay

Inventors

• Gupta Shalabh
• Sidhique Aboobackkar

Classifications

• H04B10/801 Primary

  using optical interconnects, e.g. light coupled isolators, circuit board interconnections · CPC title

• H04B10/294

  in a multiwavelength system, e.g. gain equalisation · CPC title

• H04B10/6151

  comprising a polarization controller at the receiver's input stage · CPC title

• H04B10/2581 Primary

  Multimode transmission · CPC title

• H04B10/6162

  Compensation of polarization related effects, e.g., PMD, PDL · CPC title