Polarization state aligner (PSA)

Patent metadata

Field	Value
Publication number	US-9819420-B2
Application number	US-201615057379-A
Country	US
Kind code	B2
Filing date	Mar 1, 2016
Priority date	Mar 2, 2015
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

A system comprises: a polarization state aligner (PSA) comprising: an input port; a first polarization beam splitter (PBS) coupled to the input port; a first phase shifter (PS) coupled to the first PBS; a first polarization rotator (PR) coupled to the first PBS; a first beam splitter (BS) coupled to the first PS and the first PR; a first output port coupled to the first BS; and a second output port coupled to the first BS.

First claim

What is claimed is:

1. A system comprising:
a polarization state aligner (PSA) comprising:
an input port;
a first polarization beam splitter (PBS) coupled to the input port;
a first phase shifter (PS) coupled to the first PBS along a first path of light propagation;
a first polarization rotator (PR) coupled to the first PBS along a second path of light promotion, wherein the first path and the second path are independent of each other;
a first beam splitter (BS) coupled to the first PS and the first PR;
a first output port coupled to the first BS; and
a second output port coupled to the first BS.

2. The system of claim 1 , further comprising:
a receiver coupled to the PSA and comprising:
a second PBS;
a first 90 degree (°) hybrid mixer coupled to the second PBS and the first output port;
first photodiodes (PDs) coupled to the first 90° hybrid mixer;
first transimpedance amplifiers (TIAs) coupled to the first PDs; and
a digital signal processor (DSP) coupled to the first TIAs.

3. The system of claim 2 , wherein the receiver further comprises:
a second PR coupled to the second PBS;
a second 90° hybrid mixer coupled to the second PR and the first BS;
second PDs coupled to the second 90° hybrid mixer; and
second TIAs coupled to the second PDs and the DSP.

4. The system of claim 1 , further comprising a modulator system coupled to the PSA and comprising:
an in-phase (I) modulator coupled to the first output port;
a quadrature phase (Q) modulator coupled to the second output port;
a second PS coupled to the Q modulator; and
a beam combiner (BC) coupled to the I modulator and the second PS.

5. The system of claim 4 , wherein the I modulator and the Q modulator comprise Mach-Zelmder modulators (MZMs).

6. The system of claim 1 , further comprising a modulator system coupled to the PSA and comprising:
an X component (X) modulator coupled to the first output port;
a Y component (Y) modulator coupled to the second output port;
a second PR coupled to the Y modulator; and
a polarization beam combiner (PBC) coupled to the X modulator and the second PR.

7. The system of claim 6 , wherein the X modulator and the Y modulator are any combination of Mach-Zehnder modulators (MZMs), electro-absorption (EA) modulators, or in-phase and quadrature phase (IQ) modulators.

8. The system of claim 1 , further comprising a modulator system coupled to the PSA and comprising:
a second BS coupled to the first output port;
a first modulator coupled to the second BS;
a second modulator coupled to the second BS;
a third BS coupled to the second output port;
a third modulator coupled to the third BS; and
a fourth modulator coupled to the third BS.

9. The system of claim 8 , further comprising a substrate, wherein the PSA and the modulator system are integrated on the substrate.

10. The system of claim 1 , further comprising a waveguide medium coupling the first PBS to the input port, the first PS to the first PBS, the first PR to the first PBS, the first BS to the first PS and the first PR, the first output port to the first BS, and the second output port to the first BS.

11. The system of claim 10 , wherein the waveguide medium comprises air.

12. The system of claim 10 , wherein the waveguide medium comprises one of silicon (Si), silicon dioxide (SiO 2 ), or indium phosphide (InP).

13. The system of claim 1 , wherein the first PBS is configured to:
receive an input light; and
split the input light into a first light with a first polarization and a second light with a second polarization, wherein the first polarization and the second polarization are orthogonal to each other.

14. The system of claim 13 , wherein the first polarization is a transverse electric (TE) polarization and the second polarization is a transverse magnetic (TM) polarization.

15. The system of claim 1 , wherein the first PS is directly coupled to the first PBS and the first BS, and wherein the first PR is directly coupled to the first PBS and the first BS.

16. A system comprising:
a polarization state aligner (PSA) configured to:
receive an input light from an optical component at an input polarization;
split the input light into a first light and a second light, wherein the first light comprises an output polarization corresponding to an optoelectronic circuit, and wherein the second light comprises a first polarization;
rotate the first polarization to the output polarization;
combine the first light and the second light;
provide to the optoelectronic circuit a first output light associated with the first light and a second output light associated with the second light; and
adjust a phase of the first light so that the first output light and the second output light have a same power,
wherein the first output light and the second output light comprise the output polarization.

17. The system of claim 16 , wherein the input polarization is any arbitrary polarization, the output polarization is a transverse electric (FE) polarization, and the first polarization is a transverse magnetic (TM) polarization.

18. A system comprising:
a polarization state aligner (PSA) comprising:
a polarization beam splitter (PBS) configured to:
receive an input light from an optical component at an input polarization; and
split the input light into a first light and a second light, wherein the first light comprises an output polarization corresponding to an optoelectronic circuits and wherein the second light comprises a first polarization;

a polarization rotator (PR) coupled to the PBS and configured to rotate the first polarization to the output polarization; and
a phase shifter (PS) coupled to the PBS and configured to shift a first phase of the first light to a second phase so that a phase delay between the first light and the second light is an integer multiple of π,

wherein the PSA is configured to:
combine the first light and the second light; and
provide to the optoelectronic circuit a first output light associated with the first light and a second output light associated with the second light, and

wherein the first output light and the second output light comprise the output polarization.

19. A system comprising:
a polarization state aligner (PSA) comprising:
a polarization splitter-rotator (PSR) configured to:
receive an input light from an optical component at an input polarization;
split the input light into a first light and a second light, wherein the first light comprises an output polarization corresponding to an optoelectronic circuit, and wherein the second light comprises a first polarization; and
rotate the first polarization to the output polarization; and

a phase shifter (PS) coupled to the PSR and configured to shift a first phase of the second light to a second phase so that a phase delay between the first light and the second light is an integer multiple of π,

wherein the PSA is configured to:
combine the first light and the second light; and
provide to the optoelectronic circuit a first output light associated with the first light and a second output light associated with the second light, and

wherein the first output light and the second output light comprise the output polarization.

20. The system of claim 16 , wherein the optical component is a standard single-mode fiber (SSMF) that does not maintain polarization.

21. A method comprising:
receiving an input light from an optical component at an input polarization;
splitting the input light int

Assignees

• Futurewei Technologies Inc
• Futurewei Technolgies Inc

Inventors

• Wen Yangjing
• Zhu Fei
• Bai Yu Sheng

Classifications

• H04B10/532

  Polarisation modulation · CPC title

• H04B10/614 Primary

  comprising one or more polarization beam splitters, e.g. polarization multiplexed [PolMux] X-PSK coherent receivers, polarization diversity heterodyne coherent receivers (H04J14/06 takes precedence) · CPC title

• H04B10/5053

  using a parallel, i.e. shunt, combination of modulators · CPC title

• G02B6/272

  comprising polarisation means for beam splitting and combining · CPC title

• H04B10/6151

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