Free space optical communication system and method

Patent metadata

Field	Value
Publication number	US-11038593-B2
Application number	US-202016856479-A
Country	US
Kind code	B2
Filing date	Apr 23, 2020
Priority date	Oct 5, 2016
Publication date	Jun 15, 2021
Grant date	Jun 15, 2021

Abstract

A free-space optical communication method is provided. An example method may include generating an optical frequency comb comprising a first tone and a second tone different from the first tone. The method may include modulating, by a first modulator of a first device, the first tone to generate a first signal comprising data. The method may include modulating, by a second modulator of the first device, the second tone to generate a second signal that is a phase conjugate of the first signal. The method may include transmitting, via free-space and to a second device, a communication signal having the first signal and the second signal.

First claim

What is claimed is:

1. A method, comprising:
generating an optical frequency comb comprising a first tone and a second tone different from the first tone;
modulating, by a first modulator of a first device, the first tone to generate a first signal comprising data;
modulating, by a second modulator of the first device, the second tone to generate a second signal that is a phase conjugate of the first signal; and
transmitting, via free-space and to a second device, a communication signal having the first signal and the second signal.

2. The method of claim 1 , further comprising splitting the first tone from the second tone in the optical frequency comb prior to modulating the first tone and the second tone.

3. The method of claim 2 , further comprising multiplexing the first signal and the second signal to produce the communication signal.

4. The method of claim 1 , further comprising amplifying the communication signal prior to the transmitting the communication signal.

5. The method of claim 1 , wherein the first tone and the second tone comprise frequencies that are equally spaced from a frequency of a pump signal.

6. The method of claim 1 , wherein the first tone is modulated using in-phase modulation and the second tone is modulated using quadrature phase modulation.

7. The method of claim 1 , further comprising:
generating a pump signal;
splitting the pump signal into a first portion used to generate the optical frequency comb and a second portion;
attenuating the second portion of the pump signal; and
multiplexing the attenuated second portion of the pump signal with the first signal and the second signal to generate the communication signal.

8. A device comprising:
one or more processors; and
memory storing instructions that, when executed by the one or more processors, cause the device to:
cause output of an optical signal, wherein an optical frequency comb is generated based on the optical signal and comprises a first tone and a second tone different from the first tone;
modulate, by a first modulator of the device, the first tone to generate a first signal comprising data; and
modulate, by a second modulator of the device, the second tone to generate a second signal that is a phase conjugate of the first signal, wherein a communication signal comprising the first signal and the second signal is output via free space.

9. The device of claim 8 , wherein the first tone is split from the second tone in the optical frequency comb prior to modulating the first tone and the second tone.

10. The device of claim 8 , wherein the first signal and the second signal are multiplexed to produce the communication signal.

11. The device of claim 8 , wherein the communication signal is amplified prior to the transmitting the communication signal.

12. The device of claim 8 , wherein the first tone and the second tone comprise frequencies that are equally spaced from a frequency of the optical signal.

13. The device of claim 8 , wherein the first tone is modulated using in-phase modulation and the second tone is modulated using quadrature phase modulation.

14. The device of claim 8 , wherein the optical signal is split into a first portion used to generate the optical frequency comb and a second portion, wherein the second portion is attenuated and the attenuated second portion is multiplexed with the first signal and the second signal to generate the communication signal.

15. A non-transitory computer-readable medium storing computer-executable instructions that, when executed by one or more processors, cause:
modulating, by a first modulator of a first device, a first tone to generate a first signal comprising data; and
modulating, by a second modulator of the first device, a second tone to generate a second signal that is a phase conjugate of the first signal, wherein the first tone and the second tone are separate tones and from an optical frequency comb, and wherein a communication signal comprising the first signal and the second signal is transmitted via free space to a second device.

16. The non-transitory computer-readable medium of claim 15 , wherein the first tone is split from the second tone in the optical frequency comb prior to modulating the first tone and the second tone.

17. The non-transitory computer-readable medium of claim 16 , wherein the first signal and the second signal are multiplexed to produce the communication signal.

18. The non-transitory computer-readable medium of claim 15 , wherein the first tone and the second tone comprise frequencies that are equally spaced from a frequency of a pump signal.

19. The non-transitory computer-readable medium of claim 15 , wherein the first tone is modulated using in-phase modulation and the second tone is modulated using quadrature phase modulation.

20. The non-transitory computer-readable medium of claim 15 , wherein the instructions, when executed by one or more processors, further cause generating a pump signal, wherein the pump signal is split into a first portion used to generate the optical frequency comb and a second portion, and wherein the second portion is attenuated and the attenuated second portion is multiplexed with the first signal and the second signal to generate the communication signal.

Assignees

• Caci Inc Fed

Inventors

• Legrange Jane Deborah
• Kang Inuk

Classifications

• H04B10/118

  specially adapted for satellite communication · CPC title

• H04B10/293 Primary

  Signal power control · CPC title

• H04B10/1121

  One-way transmission · CPC title

• H04B10/11

  Arrangements specific to free-space transmission, i.e. transmission through air or vacuum · CPC title