[1] [1] F. I. Oluwajobi, N. Dong-Nhat, A. Malekmohammadi, IET Optoelectronics 12, 202 (2018).

[2] [2] M. H. Yao and Q. L. Gu, Optoelectronics Letters 14, 476 (2018).

[3] [3] H. F. Bai, Optoelectronics Letters 14, 114 (2018).

[4] [4] K. Yu, W. L. Yang and Y. Yu, Optics Communications 377, 139 (2016).

[5] [5] K. Mishina, A. Maruta, S. Mitani, T. Miyahara, K. Ishida, K. Shimizu, T. Hatta, K. Motoshima and K. Ki-tayama, All-optical format conversion from NRZ-OOK to RZ-BPSK using SOA-MZI wavelength converter, Optical Fiber Communication Conference and Exposi-tion and The National Fiber Optic Engineers Confer-ence, OThB2 (2006).

[6] [6] A. Bogoni, X. Wu, S.R. Nuccio, A. E. Willner, J. Lightw. Technol. 30, 1829 (2012).

[7] [7] K. Yu, Y. Y. LIU and Q. Bao, Optics and Laser Technol. 56, 71 (2014).

[8] [8] D. McGhan, C. Laperle, A. Savchenko, C. Li, G. Mark and M.O’Sullivan, 5120 km RZ-DPSK transmission over G652 fiber at 10 Gb/s with no optical dispersion compensation, Optical Fiber Communication Confer-ence and Exposition and The National Fiber Optic En-gineers Conference, PDP27 (2005).

[9] [9] K. Yu, J. J. Yin, D. X. Huang and J. Q. Bao, Optik 125, 397 (2014).

[10] [10] Z. Zhang, Y. Yu and X.L. Zhang, Optics Express 19, 12427 (2011).

[11] [11] J. Parra-Cetina, S. Latkowski, R. Maldonado-Basilio and P. Landais, Photonics Technology Letters 25, 2339 (2013).

[12] [12] C. J. McKinstrie and S. Radic, Optics Express 12, 4973 (2004).