[1] Kawasaki B S, Hill K O, Johnson D C. Optical time domain reflectometer for single-mode fiber at selectable wavelengths[J]. Applied Physics Letters, 38, 740-742(1981).

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

[3] Blank L C, Spirit D M. OTDR performance enhancement through erbium fibre amplification[J]. Electronics Letters, 25, 1693-1694(1989).

[4] Zhu N H, Tong Y W, Chen W et al. Improved wavelength coded optical time domain reflectometry based on the optical switch[J]. Optics Express, 22, 15111-15117(2014).

[5] Eickhoff W, Ulrich R. Optical frequency-domain reflectometry in single-mode fibers[J]. Applied Physics Letters, 39, 693-695(1981).

[6] Soller B J, Gifford D K, Wolfe M S et al. High resolution optical frequency domain reflectometry for characterization of components and assemblies[J]. Optics Express, 13, 666-674(2005).

[7] Venkatesh S, Sorin W V. Phase noise considerations in coherent optical FMCW reflectometry[J]. Journal of Lightwave Technology, 11, 1694-1700(1993).

[8] Yuksel K, Wuilpart M, Mégret P. Analysis and suppression of nonlinear frequency modulation in an optical frequency-domain reflectometer[J]. Optics Express, 17, 5845-5851(2009).

[9] Geng J H, Spiegelberg C, Jiang S B. Narrow linewidth fiber laser for 100-km optical frequency domain reflectometry[J]. IEEE Photonics Technology Letters, 17, 1827-1829(2005).

[10] Ding Z Y, Yao X S, Liu T G et al. Long measurement range OFDR beyond laser coherence length[J]. IEEE Photonics Technology Letters, 25, 202-205(2013).

[11] Venkatesh S, Sorin W V. Phase noise considerations in coherent optical FMCW reflectometry[J]. Journal of Lightwave Technology, 11, 1694-1700(1993).

[12] Amann M C. Phase noise limited resolution of coherent LIDAR using widely tunable laser diodes[J]. Electronics Letters, 28, 1694-1696(1992).

[13] von der Weid J P, Passy R, Mussi G et al. On the characterization of optical fiber network components with optical frequency domain reflectometry[J]. Journal of Lightwave Technology, 15, 1131-1141(1997).

[14] Liu Q W, Fan X Y, He Z Y. Time-gated digital optical frequency domain reflectometry with 1.6-m spatial resolution over entire 110-km range[J]. Optics Express, 23, 25988-25995(2015).

[15] Wei F, Lu B, Wang J et al. Precision and broadband frequency swept laser source based on high-order modulation-sideband injection-locking[J]. Optics Express, 23, 4970-4980(2015).

[16] Hotate K, Yamauchi T. Fiber-optic distributed strain sensing system by Brillouin optical correlation domain analysis with a simple and accurate time-division pump-probe generation scheme[J]. Japanese Journal of Applied Physics, 44, L1030-L1033(2005).

[17] Fan X Y, Koshikiya Y, Ito F. Phase-noise-compensated optical frequency domain reflectometry with measurement range beyond laser coherence length realized using concatenative reference method[J]. Optics Letters, 32, 3227-3229(2007).

[18] Qin J, Shi H X, Xie W L et al. Precise linearization of broadband frequency chirp for coherent optical frequency domain reflectometry[J]. Proceedings of SPIE, 9619, 96190A(2015).

[19] Takada K. High-resolution OFDR with incorporated fiber-optic frequency encoder[J]. IEEE Photonics Technology Letters, 4, 1069-1072(1992).

[20] Passy R, Gisin N, von der Weid J P et al. Experimental and theoretical investigations of coherent OFDR with semiconductor laser sources[J]. Journal of Lightwave Technology, 12, 1622-1630(1994).

[21] Ahn T J, Lee J Y, Kim D Y. Suppression of nonlinear frequency sweep in an optical frequency-domain reflectometer by use of Hilbert transformation[J]. Applied Optics, 44, 7630-7634(2005).

[22] Hahn S L[M]. Hilbert transforms in signal processing(1996).

[23] Ang K H, Chong G, Li Y. PID control system analysis, design, and technology[J]. IEEE Transactions on Control Systems Technology, 13, 559-576(2005).

[24] Chen D, Liu Q W, He Z Y. 108-km distributed acoustic sensor with 220-p/Hz strain resolution and 5-m spatial resolution[J]. Journal of Lightwave Technology, 37, 4462-4468(2019).

[25] Liu T G, Liu K, Dai L et al. Research progress of key technologies in recognition sensing for opto-electronic information and event[J]. Acta Optica Sinica, 41, 0106002(2021).

[26] Zhang X P, Ding Z W, Hong R et al. Phase sensitive optical time-domain reflective distributed optical fiber sensing technology[J]. Acta Optica Sinica, 41, 0106004(2021).