Distributed acoustic sensing gauge length effect mitigation

1. A system, comprising:

a light source;

optical fiber coupled to the light source;

one or more interferometers coupled to the optical fiber, each interferometer of the one or more interferometers comprising a gauge length;

a photodetector assembly coupled to the optical fiber and configured to detect backscattered light from the optical fiber and generate signals based on the detected backscattered light; and

an information handling system configured to:

receive the signals from the photodetector assembly;

apply a de-convolution operation to the signals based on the gauge lengths of the one or more interferometers; and

store the de-convolved signals.

2. The system of claim 1 , wherein the de-convolution operation is based on a subtraction model using a difference in strain between ends of the gauge lengths of the one or more interferometers.

3. The system of claim 1 , wherein the de-convolution operation is based on a summation model using a sum of strain between ends of the gauge lengths of the one or more interferometers.

4. The system of claim 1 , wherein applying a de-convolution operation to the signals includes applying an inverse transform comprising a truncated infinite series, the inverse transform being an inverse Z-transform or an inverse Fourier transform.

5. The system of claim 4 , wherein the information handling system is further configured to apply a weighting function to the truncated infinite series.

6. The system of claim 5 , wherein the weighting function is linear or exponential.

7. The system of claim 1 , wherein the information handling system is further configured to apply weights to the signals from the photo detector assembly prior to applying the de-convolution operation to the signals.

8. The system of claim 1 , wherein applying the de-convolution operation to the signals based on the gauge lengths of the one or more interferometers comprises:

applying a first de-convolution operation based on a first gauge length of a first interferometer of the one or more interferometers; and

applying a second de-convolution operation based on a second gauge length of a second interferometer of the one or more interferometers.

9. A method, comprising:

receiving signals from a photodetector assembly coupled to a distributed acoustic sensing (DAS) system;

applying a de-convolution operation to the signals based on gauge lengths of one or more interferometers of the DAS system; and

storing the de-convolved signals.

10. The method of claim 9 , wherein the de-convolution operation is based on a subtraction model using a difference in strain between ends of the gauge lengths of the one or more interferometers.

11. The method of claim 9 , wherein the de-convolution operation is based on a summation model using a sum of strain between ends of the gauge lengths of the one or more interferometers.

12. The method of claim 9 , wherein applying a de-convolution operation to the signals includes applying an inverse transform comprising a truncated infinite series, the inverse transform being an inverse Z-transform or an inverse Fourier transform.

13. The method of claim 12 , further comprising applying a weighting function to the truncated infinite series.

14. The method of claim 13 , wherein the weighting function is linear or exponential.

15. The method of claim 9 , further comprising applying weights to the signals from the photo detector assembly prior to applying the de-convolution operation to the signals.

16. The method of claim 9 , wherein applying the de-convolution operation to the signals based on the gauge lengths of the one or more interferometers comprises:

applying a first de-convolution operation based on a first gauge length of a first interferometer of the DAS system; and

applying a second de-convolution operation based on a second gauge length of a second interferometer of the DAS system.

17. A computer-readable non-transitory medium comprising instructions that, when executed by a processor, cause a processor to:

receive signals from a photodetector assembly coupled to a distributed acoustic sensing (DAS) system;

apply a de-convolution operation to the signals based on gauge lengths of one or more interferometers of the DAS system; and

store the de-convolved signals.

18. The computer-readable medium of claim 17 , wherein the de-convolution operation is based on a subtraction model using a difference in strain between ends of the gauge lengths of the one or more interferometers.

19. The computer-readable medium of claim 17 , wherein the de-convolution operation is based on a summation model using a sum of strain between ends of the gauge lengths of the one or more interferometers.

20. The computer-readable medium of claim 17 , wherein applying a de-convolution operation to the signals includes applying an inverse transform comprising a truncated infinite series, the inverse transform being an inverse Z-transform or an inverse Fourier transform.

21. The computer-readable medium of claim 20 , further comprising instructions that, when executed, cause the processor to apply a weighting function to the truncated infinite series.

22. The computer-readable medium of claim 21 , wherein the weighting function is linear or exponential.

23. The computer-readable medium of claim 17 , further comprising instructions that, when executed, cause the processor to apply weights to the signals from the photo detector assembly prior to applying the de-convolution operation to the signals.

24. The computer-readable medium of claim 17 , wherein the instructions that cause the processor to apply the de-convolution operation to the signals based on the gauge lengths of the one or more interferometers further comprise instruction that cause the processor to:

apply a first de-convolution operation based on a first gauge length of a first interferometer of the DAS system; and

apply a second de-convolution operation based on a second gauge length of a second interferometer of the DAS system.