[1] [1] Barnoski M K, Rourke M D, Jensen S M, et al. Optical time domain reflectometer［J］. Applied Optics, 1977, 16(9): 2375-2379.

[2] [2] Froggatt M, Moore J. High-spatial-resolution distributed strain measurement in optical fiber with Rayleigh scatter［J］. Applied Optics, 1998, 37(10): 1735-1740.

[3] [3] Farahani M A, Gogolla T. Spontaneous Raman scattering in optical fibers with modulated probe light for distributed temperature Raman remote sensing［J］. Journal of Lightwave Technology, 1999, 17(8): 1379-1391.

[4] [4] Dakin J P, Pratt D J, Bibby G W, et al. Distributed optical fibre Raman temperature sensor using a semiconductor light source and detector［J］. Electronics Letters, 1985, 21(13): 569-570.

[5] [5] Horiguchi T, Shimizu K, Kurashima T, et al. Development of a distributed sensing technique using Brillouin scattering［J］. Journal of Lightwave Technology, 1995, 13(7): 1296-1302.

[6] [6] Kurashima T, Horiguchi T, Tateda M. Distributed-temperature sensing using stimulated Brillouin scattering in optical silica fibers［J］. Optics Letters, 1990, 15(18): 1038-1040.

[7] [7] Horiguchi T, Kurashima T, Tateda M. Tensile strain dependence of Brillouin frequency shift in silica optical fibers［J］. IEEE Photonics Technology Letters, 1989, 1(5): 107-108.

[8] [8] Lopez-Higuera J M, Rodriguez C L, Quintela I A, et al. Fiber optic sensors in structural health monitoring［J］. Journal of Lightwave Technology, 2011, 29(4): 587-608.

[9] [9] Bao X, Chen L. Recent progress in Brillouin scattering based fiber sensors［J］. Sensors, 2011, 11(4): 4152-4187.

[10] [10] Alahbabi M N, Cho Y T, Newson T P. 150-km-range distributed temperature sensor based on coherent detection of spontaneous Brillouin backscatter and in-line Raman amplification［J］. Journal of the Optical Society of America B, 2005, 22(6): 1321-1324.

[11] [11] Voskoboinik A, Zhang Z Y, Almaiman A, et al. Differential pulse-width pair BOTDA using simultaneous frequency domain interrogation［C］∥Conference on Lasers and Electro-Optics: Science and Innovations. San Jose, California United States, 2013, CTh4H: CTh4H.5.

[12] [12] Soto M A, Taki M, Bolognini G, et al. Optimization of a DPP-BOTDA sensor with 25 cm spatial resolution over 60 km standard single-mode fiber using Simplex codes and optical pre-amplification［J］. Optics Express, 2012, 20(7): 6860-6869.

[13] [13] Kishida K, Li C H, Nishiguchi K. Pulse pre-pump method for cm-order spatial resolution of BOTDA［J］. Proceedings of SPIE, 2005, 5855: 559-562.

[14] [14] Brown A W, Colpitts B G, Brown K. Distributed sensor based on dark-pulse Brillouin scattering［J］. IEEE Photonics Technology Letters, 2005, 17(7): 1501-1503.

[15] [15] Soto M A, Ramírez J A, Thévenaz L. Intensifying the response of distributed optical fibre sensors using 2D and 3D image restoration［J］. Nature Communications, 2016, 7: 10870.

[16] [16] He H, Shao L, Li H, et al. SNR enhancement in phase-sensitive OTDR with adaptive 2-D bilateral filtering algorithm［J］. IEEE Photonics Journal, 2017, 9(3): 1-10.

[17] [17] Soto G, Fontbona J, Cortez R, et al. An online two-stage adaptive algorithm for strain profile estimation from noisy and abruptly changing BOTDR data and application to underground mines［J］. Measurement, 2016, 92: 340-351.

[18] [18] Yan Z, Gu H M, Cai C G. Seismic image enhancement based on anisotropic diffusion［J］. Oil Geophysical Prospecting, 2013, 48(3): 390-394.

[19] [19] Li G M, Feng L. Image processing the enhancement of the seismic fault of method and its application［J］. Progress in Geophysics, 2012, 27(5): 2138-2143.

[20] [20] Bartyzel K. Adaptive Kuwahara filter［J］. Signal, Image and Video Processing, 2016, 10(4): 663-670.

[21] [21] Agrawal G P. Nonlinear fiber optics［M］. 3rd Ed. San Diego: Academic Press, 2001: 195-211.

[22] [22] Soto M A, Ramírez J A, Thévenaz L. Intensifying Brillouin distributed fibre sensors using image processing［J］. Proceedings of SPIE, 2015, 9634: 96342D.

[23] [23] Azad A K,Khan F N, Alarashi W H, et al. Temperature extraction in Brillouin optical time-domain analysis sensors using principal component analysis based pattern recognition［J］. Optics Express, 2017, 25(14): 16534-16549.

[24] [24] Zhang Y J, Xu J R, Fu X H. Method of Brillouin scattering spectrum character extraction based on genetic algorithm and quantum-behaved particle swarm optimization hybrid algorithm［J］. Chinese Journal of Lasers, 2016, 43(2): 0205002.

[25] [25] Liu Y, Fu G W, Zhang Y J, et al. A novel method for Brillouin scattering spectrum of distributed sensing systems based on radial basis function neural networks to extract features［J］. Acta Optica Sinica, 2012, 32(2): 0206002.

[26] [26] Shang Q F, Hu Y T, Liu W. Feature extraction of Brillouin scattering spectrum based on cross-correlation convolution and high-order centroid calculation［J］. Chinese Journal of Lasers, 2017, 44(11): 1106011

[27] [27] Buades A, Coll B, Morel J M.A review of image denoising algorithms, with a new one［J］. Multiscale Modeling & Simulation, 2005, 4(2): 490-530.

[28] [28] Papari G, Petkov N, Campisi P. Artistic edge and corner enhancing smoothing［J］. IEEE Transactions on Image Processing, 2007, 16(10): 2449-2462.