Method and apparatus for acoustic data transmission in a subterranean well

• US 8,472,282 B2
• Filed: 12/03/2008
• Issued: 06/25/2013
• Est. Priority Date: 12/04/2006
• Status: Active Grant

• Current Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Original Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Inventors: Fink, Kevin D., Kyle, Donald G., Fripp, Michael L.
• Primary Examiner(s): WONG, ALBERT KANG
• Application Number:
  US12/256,352
• Publication Number:
  US 20090073809A1
• Time in Patent Office: 1,665 Days
• Field of Search: 367 82- 83, 367/43, 367/56, 340/854.3
• US Class Current: 367/82
• CPC Class Codes: E21B 47/16 through the drill string or casing , e.g. by torsional acoustic waves
• CPC Class Codes: G01V 11/002 Details, e.g. power supply systems for logging instruments, transmitting or recording data, specially adapted for well logging, also if the prospecting method is irrelevant means for transmitting well survey signals E21B47/12; signal transmission systems in general G08C; transmission in general H04B

Abstract

The disclosure describes a method and apparatus for effectively communicating data along an acoustic transmission path. The method comprises driving an acoustic transmitter to send a data signal along the acoustic transmission path, where the signal is distorted by ambient noise. The distorted signal is input to a spaced apart plurality of sensors so that consequent time-delayed signals provide reinforcement of the basic signal and attenuation of the ambient noise component when combined.

Claims

1. A method of data transmission along in an oil well environment, the oil well having a subterranean wellbore extending from the surface into the earth, the oil well having an acoustic transmission channel along which acoustic transmissions travel, the method comprising the steps of:

providing an acoustic transmitter at a position along the acoustic channel;

providing an acoustic receiver having a series of acoustic sensors, the sensors spaced apart from one another along the acoustic channel;

the transmitter and receiver spaced apart along an acoustic transmission channel and electrically isolated from one another;

transmitting a series of acoustic transmitted signals, the series of acoustic transmitted signals comprising a repeated, time-delayed versions of a selected signal, the series of acoustic transmitted signals transmitted from the transmitter, along the acoustic channel, where the acoustic transmitted signals are distorted by ambient noise;

sensing the series of distorted acoustic transmitted signals at the series of acoustic sensors, each signal corresponding to a sensor, each signal arriving at its corresponding sensor simultaneously;

then

creating a plurality of sensor output signals corresponding to the series of acoustic transmitted signals; and

combining the sensor output signals to provide a combined signal being less distorted than any of the distorted acoustic transmitted signals.

2. The method of claim 1, further comprising the step of receiving reflected signals at the series of sensors;

and

further comprising the step of unevenly weighting the sensor output signals prior to the step of combining.

3. The method of claim 1, further comprising the step of unevenly weighting the series of acoustic transmitted signals prior to transmitting them along the acoustic channel.

4. The method of claim 2, further comprising the step of unevenly weighting the series of acoustic transmitted signals prior to transmitting them along the acoustic channel.

5. The method of claim 4 wherein the weighting of the output signals or the acoustic transmitted signals is reconfigurable.

6. The method according to claim 4, wherein the step of combining further comprises:

multiplying or summing the sensor output signals.

7. The method according to claim 6, wherein the ambient noise is effectively filtered from the receiver signal.

8. The method according to claim 4 wherein the uneven weighting takes the following form:

[−

1 1 1 1].

9. The method according to claim 1, further comprising the step of magnifying the amplitude of the acoustic transmitted signals.

10. The method according to claim 4, further comprising the step of decreasing the magnitude of the amplitude of the ambient noise.

11. The method as in claim 1, wherein the series of sensors are spaced equidistantly apart.

12. The method as in claim 1, wherein the series of acoustic transmitted signals overlap.