Methods of acoustically communicating and wells that utilize the methods

Patent metadata

Field	Value
Publication number	US-10167716-B2
Application number	US-201715666324-A
Country	US
Kind code	B2
Filing date	Aug 1, 2017
Priority date	Aug 30, 2016
Publication date	Jan 1, 2019
Grant date	Jan 1, 2019

Abstract

Methods of acoustically communicating and wells that utilize the methods are disclosed herein. The methods generally utilize an acoustic wireless network including a plurality of nodes spaced-apart along a length of a tone transmission medium. In some embodiments, the methods include methods of communicating when the acoustic wireless network is spectrum-constrained.

First claim

The invention claimed is:

1. A method of communicating in an acoustic wireless network that is spectrum-constrained and includes a plurality of nodes spaced-apart along a length of a tone transmission medium, the method comprising:
encoding an encoded character with an encoding node of the plurality of nodes, wherein the encoding includes:
(i) selecting, based upon the encoded character and from a first predetermined lookup table, a first frequency for a first transmitted acoustic tone;
(ii) transmitting the first transmitted acoustic tone, at the first frequency, via the tone transmission medium;
(iii) selecting, based upon the encoded character and from a second predetermined lookup table, a second frequency for a second transmitted acoustic tone, wherein the second frequency is different from the first frequency; and
(iv) transmitting the second transmitted acoustic tone, at the second frequency, via the tone transmission medium; and
decoding a decoded character with a decoding node of the plurality of nodes, wherein the decoding includes:
(i) responsive to the transmitting the first transmitted acoustic tone, receiving a first received acoustic tone from the tone transmission medium;
(ii) calculating a first frequency distribution for the first received acoustic tone;
(iii) determining, from the first frequency distribution and the first predetermined lookup table, a first decoded character distribution for the decoded character;
(iv) responsive to the transmitting the second transmitted acoustic tone, receiving a second received acoustic tone from the tone transmission medium;
(v) calculating a second frequency distribution for the second received acoustic tone;
(vi) determining, from the second frequency distribution and the second predetermined lookup table, a second decoded character distribution for the decoded character; and
(vii) identifying the decoded character based, at least in part, on the first decoded character distribution and the second decoded character distribution.

2. The method of claim 1 , wherein the decoding node is spaced-apart from the encoding node such that the tone transmission medium extends between the encoding node and the decoding node.

3. The method of claim 1 , wherein the method further includes conveying the first transmitted acoustic tone from the encoding node to the decoding node via the tone transmission medium, and further wherein the conveying the first transmitted acoustic tone includes modifying the first transmitted acoustic tone, via a first interaction between the first transmitted acoustic tone and the tone transmission medium, to generate the first received acoustic tone.

4. The method of claim 1 , wherein the method further includes conveying the second transmitted acoustic tone from the encoding node to the decoding node via the tone transmission medium, and further wherein the conveying the second transmitted acoustic tone includes modifying the second transmitted acoustic tone, via a second interaction between the second transmitted acoustic tone and the tone transmission medium, to generate the second received acoustic tone.

5. The method of claim 1 , wherein the tone transmission medium includes at least one of:
(i) a downhole tubular that extends within a wellbore;
(ii) a wellbore fluid that extends within the wellbore;
(iii) a subterranean formation that defines the wellbore;
(iv) a cement that extends within the wellbore;
(v) a subsea tubular that extends within a subsea environment; and
(vi) a subsea fluid that extends within the subsea environment.

6. The method of claim 1 , wherein the second predetermined lookup table is different from the first predetermined lookup table.

7. The method of claim 1 , wherein the first frequency is correlated to the encoded character in the first predetermined lookup table.

8. The method of claim 1 , wherein the second frequency is correlated to the encoded character in the second predetermined lookup table.

9. The method of claim 1 , wherein the first predetermined lookup table provides a one-to-one correspondence between the first frequency and the encoded character.

10. The method of claim 1 , wherein the second predetermined lookup table provides a one-to-one correspondence between the second frequency and the encoded character.

11. The method of claim 1 , wherein the first predetermined lookup table includes a plurality of characters and a corresponding plurality of first frequencies, wherein each character in the plurality of characters corresponds to only one first frequency of the plurality of first frequencies.

12. The method of claim 11 , wherein the second predetermined lookup table includes the plurality of characters and a corresponding plurality of second frequencies, wherein each character in the plurality of characters corresponds to only one second frequency of the plurality of second frequencies.

13. The method of claim 12 , wherein the plurality of first frequencies and the plurality of second frequencies both include the same plurality of frequencies.

14. The method of claim 12 , wherein a different frequency corresponds to each character in the plurality of characters in the first predetermined lookup table when compared to the second predetermined lookup table.

15. The method of claim 12 , wherein the plurality of first frequencies and the plurality of second frequencies are selected such that, for a given character in the plurality of characters, a corresponding first frequency of the plurality of first frequencies is unequal to a corresponding second frequency of the plurality of second frequencies.

16. The method of claim 12 , wherein the plurality of first frequencies and the plurality of second frequencies are selected such that, for the given character in the plurality of characters, the corresponding first frequency is not a harmonic of the corresponding second frequency within the tone transmission medium.

17. The method of claim 1 , wherein the transmitting the first transmitted acoustic tone includes transmitting the first transmitted acoustic tone for a first tone-transmission duration.

18. The method of claim 1 , wherein the transmitting the second transmitted acoustic tone includes transmitting the second transmitted acoustic tone for a second tone-transmission duration.

19. The method of claim 1 , wherein the first frequency is at least 50 kilohertz (kHz) and at most 1000 kHz.

20. The method of claim 1 , wherein the second frequency is at least 50 kilohertz (kHz) and at most 1000 kHz.

21. The method of claim 1 , wherein the transmitting the first transmitted acoustic tone includes inducing the first transmitted acoustic tone, within the tone transmission medium, with an encoding node transmitter.

22. The method of claim 21 , wherein the transmitting the second transmitted acoustic tone includes inducing the second transmitted acoustic tone, within the tone transmission medium, with the encoding node transmitter.

23. The method of claim 21 , wherein the encoding node transmitter includes at least one of:
(i) a piezoelectric encoding node transmitter configured to induce a vibration within the tone transmission medium;
(ii) an electromagnetic acoustic transmitter configured to induce the vibration within the tone transmission medium;
(iii) a resonant microelectromechanical system (MEMS) transmitter configured to induce the vibration within the tone transmission medium;
(iv) a non-resonant MEMS transmitter

Assignees

• Clawson Scott William
• Song Limin
• Zhang Yibing
• Wolf Henry Alan
• Exxonmobil Upstream Res Co

Inventors

• Clawson Scott William
• Song Limin
• Zhang Yibing
• Wolf Henry Alan

Classifications

• H04W72/0446

  Resources in time domain, e.g. slots or frames · CPC title

• E21B47/14 Primary

  using acoustic waves · CPC title

• H04W52/0216

  using a pre-established activity schedule, e.g. traffic indication frame · CPC title

• H04W72/0453

  Resources in frequency domain, e.g. a carrier in FDMA · CPC title

• Y02D30/70

  in wireless communication networks · CPC title