[1] CANI S P N, FREITAS M, ALMEIDA R T R, et al.. Raman amplifier performance of dispersion compensating fibers ［J］. Microwave and Optoelectronics Conference, 2003，(2):553-558.

[2] HANSEN P B, ESKILDSEN L, STENTZ A J, et al.. Rayleigh scattering limitations in distributed Raman preamplifiers ［J］. IEEE Photonics Technol. Lett . , 1998,10(1):159-161.

[3] WAN P, CONRADI J. Impact of double Rayleigh backscatter noise on digital and analog fiber systems ［J］. J . Lightwave Technol.,1996,14(3):288-297.

[4] WANG S H, FAN C C. Distributed fiber Raman amplifiers: analytical expression of noise characteristics under complex conditions ［J］. Optics Communications, 2001,198(3):65-70.

[5] ALI M I M, ZAMZURI A K, AHMAD A, et al.. Experimental validation of double-pass discrete Raman amplifier limitation for large signals ［J］. IEEE Photonics Technology Letters, 2006,5(18):493- 495.

[6] GILES C R, DESURVIRE E. Modeling Erbium-doped fiber amplifiers ［J］. Journal of Lightwave Technology, 1991,9(2):271-283.

[7] KAZOVSKY L G, BENEDETTO S, WILLNER A E. Optical Fiber Communication Systems ［M］. Artech House,1996.

[8] CUI S, LIU JS, MA X M. Optimization of multiple wavelength bidirectionally pumping fiber Raman amplifier［J］. Acta Optica Sinica, China, 2004,24(12):1607-1611. (in Chinese)

[9] VANDEVENTER M O. Polarization properties of Rayleigh backscattering in single-mode fibers ［J］. J. Lightwave Technol., 1993,11(3):1895-1899.

[10] JIANG W N, CHEN J P, CHEN Y L, et al.. Suppression of double rayleigh backscattering noise in optical fiber raman amplifiers ［J］. Acta Optica Sinica, China, 2002, 22(5):539-541. (in Chinese)