[1] [1] Armstrong J. OFDM for optical communications［J］. Journal of Lightwave Technology, 2009, 27(3): 189-204.

[2] [2] Shieh W, Athaudage C. Coherent optical orthogonal frequency division multiplexing［J］. Electronics Letters, 2006, 42(10): 587-589.

[3] [3] Yang Qi, Yu Shaohua. Tb/s ultra long haul transmission of coherent optical OFDM［J］. Chinese Science Bulletin, 2014, 59(16): 1497-1507.

[4] [4] Deng Mingliang, Yi Xingwen, Yu Zhenming, et al. Improving the fiber nonlinear tolerance based on constant envelope modulation for CO-OFDM systems［J］. Journal of Optoelectronics·Laser, 2013, 24(10): 1922-1929.

[5] [5] Zhang Shuai, Bai Chenglin, Luo Qinglong, et al. Optimization of channel estimation for coherent optical OFDM systems with MMSE method［J］. Journal of Optoelectronics·Laser, 2013, 24(3): 508-513.

[6] [6] Tong Zhengrong, Guo Zunli, Cao Ye, et al. Wavelet packet transform for PAPR reduction performance in CO-OFDM system［J］. Acta Photonica Sinica, 2015, 44(12): 1206001.

[7] [7] Li Bao, Yu Jianjun, He Jing, et al. Estimation and compensation of sampling clock frequency offset in coherent optical OFDM systems with a pilot-aided method［J］. Acta Photonica Sinica, 2015, 44(1): 0106003.

[8] [8] Yi X, Shieh W, Tang Y. Phase estimation for coherent optical OFDM［J］. IEEE Photonics Technology Letters, 2007, 19(12): 919-921.

[9] [9] Zhou X, Yang X L, Li R, et al. Efficient joint carrier frequency offset and phase noise compensation scheme for high-speed coherent optical OFDM systems［J］. Journal of Lightwave Technology, 2013, 31(11): 1755-1761.

[10] [10] Liu Wu, Yang Qi. Carrier phase recovery without pilot sub-carrier in coherent optical OFDM transmission systems［J］. Acta Photonica Sinica, 2011, 40(12): 1893-1898.

[11] [11] Zhao Bo, Li Li, Han Li, et al. Phase noise compensation method based on RORC for CO-OFDM systems［J］. Journal of Optoelectronics·Laser, 2016, 27(1): 31-37.

[12] [12] Liu Jianfei, Shi Huimin, Zeng Xiangye, et al. Channel estimation method based on wavelet and improved ISFA for CO-OFDM systems［J］. Chinese J Lasers, 2015, 42(2): 0205005.

[13] [13] Su Zhenzhen, Xu Yi, Dong Ying, et al. Channel estimation based on analysis of phase noise compensation for CO-OFDM system［J］. Journal of Optoelectronics·Laser, 2013, 24(11): 2135-2141.

[14] [14] Le S T, Kanese T, Giacoumidis E, et al. Quasi-pilot aided phase noise estimation for coherent optical systems［J］. IEEE Photonics Technology Letters, 2014, 26(5): 504-507.

[15] [15] Mousa-Pasandi M E, Plant D V. Zero-overhead phase noise compensation via decision-directed phase equalizer for coherent optical OFDM［J］. Optics Express, 2010, 18(20): 20651-20660.

[16] [16] Cao S J, Kam P Y, Yu C Y. Decision-aided, pilot-aided, decision-feedback phase estimation for coherent optical OFDM［J］. IEEE Photonics Technology Letters, 2012, 24(22): 2067-2069.

[17] [17] Ha Y S, Chung W. Non-data-aided phase noise suppression scheme for CO-OFDM systems［J］. IEEE Photonics Technology Letters, 2013, 25(17): 1703-1705.

[18] [18] Zhao C X, Yang C C, Yang F, et al. A CO-OFDM system with almost blind phase noise suppression［J］. IEEE Photonics Technology Letters, 2013, 25(17): 1723-1726.

[19] [19] Mousa-Pasandi M E, Plant D V. Noniterative interpolation-based partial phase noise ICI mitigation for CO-OFDM transport systems［J］. IEEE Photonics Technology Letters, 2011, 23(21): 1594-1596.

[20] [20] Chung W. A matched filtering approach for phase noise suppression in CO-OFDM system［J］. IEEE Photonics Technology Letters, 2011, 22(24): 1802-1804.

[21] [21] Lee M K, Lim S C, Yang K. Blind compensation for phase noise in OFDM systems over constant modulus modulation［J］. IEEE Transactions on Communications, 2012, 60(3): 620-625.

[22] [22] Cao S J, Kam P Y, Yu C Y. Time-domain blind ICI mitigation for non-constant modulus format in CO-OFDM［J］. IEEE Photonics Technology Letters, 2013, 25(24): 2490-2493.

[23] [23] Ren H L, Cai J X, Ye X, et al. Decision-aided ICI mitigation with time-domain average approximation in CO-OFDM［J］. Optics Communications, 2015, 347: 1-7.

[24] [24] Liu Y, Yang C C, Li H B. Cost-effective and spectrum-efficient coherent TDM-OFDM-PON aided by blind ICI suppression［J］. IEEE Photonics Technology Letters, 2015, 27(8): 887-890.

[25] [25] Hong X Z, Hong X J, He S L. Linearly interpolated sub-symbol optical phase noise suppression in CO-OFDM system［J］. Optics Express, 2015, 23(4): 4691-4702.

[26] [26] Ren H L, Cai J X, Lu J, et al. Novel iteration-free blind phase noise estimation for coherent optical OFDM［J］. Chinese Optics Letters, 2014, 12(12): 120603.