[1] Koshikiya Y, Fan X, Ito F. Long range and cm-level spatial resolution measurement using coherent optical frequency domain reflectometry with SSB-SC modulator and narrow linewidth fiber laser[J]. Journal of Lightwave Technology, 2008, 26(18): 3287-3294.
[2] Wan Hongdan, Lu Zhiming, Hu Taoping. A high power, single-frequency, narrow linewidth fiber laser based on an active double-ring cavity[J]. Laser & Optoelectronics Progress, 2015, 52(7): 071401.
[3] Xu Dan, Lu Bin, Yang Fei, et al. Narrow linewidth single-frequency laser noise measurement based on a 3×3 fiber coupler[J]. Chinese J Lasers, 2016, 43(1): 0102004.
[5] Liu F N, Jia X J, Liu Y G, et al. Enhancing coherent combining efficiency via choosing appropriate lasing wavelength in a Michelson compound cavity based on two 3 dB fibre loop mirrors and one fibre Bragg grating[J]. Chinese Physics Letters, 2007, 24(4): 929-932.
[6] Kringlebotn J T, Archambault J L, Reekie L, et al. Er3+∶Yb3+-codoped fiber distributed-feedback laser[J]. Optics Letters, 1994, 19(24): 2101-2103.
[7] Wu L, Pei L, Liu C, et al. Research on tunable phase shift induced by piezoelectric transducer in linearly chirped fiber Bragg grating with the V-I transmission matrix formalism[J]. Optics & Laser Technology, 2016, 79: 15-19.
[8] Malara P, Campanella C E, de Leonardis F, et al. Enhanced spectral response of π-phase shifted fiber Bragg gratings in closed-loop configuration[J]. Optics Letters, 2015, 40(9): 2124-2126.
[9] Guo J, Yang C. Highlystabilized phase-shifted fiber Bragg grating sensing system for ultrasonic detection[J]. IEEE Photonics Technology Letters, 2015, 27(8): 848-851.
[10] Guy M J, Taylor J R, Kashyap R. Single-frequency erbium fibre ring laser with intracavity phase-shifted fibre Bragg grating narrowband filter[J]. Electronics Letters, 1995, 31(22): 1924-1925.
[11] Chen X, Yao J, Zeng F, et al. Single-longitudinal-mode fiber ring laser employing an equivalent phase-shifted fiber Bragg grating[J]. IEEE Photonics Technology Letters, 2005, 17(7): 1390-1392.
[12] Zhao Y, Chang J, Wang Q, et al. Research on a novel composite structure Er3+-doped DBR fiber laser with a π-phase shifted FBG[J]. Optics Express, 2013, 21(19): 22515-22522.
[13] Kogelnik H. Filter response of nonuniform almost-periodic structures[J]. Bell Labs Technical Journal, 1976, 55(1): 109-126.
[14] Yamada M, Sakuda K. Analysis of almost-periodic distributed feedback slab waveguides via a fundamental matrix approach[J]. Applied Optics, 1987, 26(16): 3474-3478.
[15] Weller-Brophy L A, Hall D G. Analysis of waveguide gratings: Application of Rouard′s method[J]. Journal of the Optical Society of America A, 1985, 2(6): 863-871.
[16] Zhou Shaoling. Theoretical analysis on characteristics of phased-shifted fiber grating[J]. Optical Communication Technology, 2003, 27(4): 47-49.
[17] Wang M, Zhang Y J, Wang Z F. Fabrication of chirped and tilted fiber Bragg gratings and suppression of stimulated Raman scattering in fiber amplifiers[J]. Optics Express, 2017, 25(2): 1529-1534.