TY - JOUR
T1 - Burst-Error-Propagation Suppression for Decision-Feedback Equalizer in Field-Trial Submarine Fiber-Optic Communications
AU - Zhou, Ji
AU - Yang, Chengkun
AU - Wang, Dawei
AU - Sui, Qi
AU - Wang, Haide
AU - Gao, Shecheng
AU - Feng, Yuanhua
AU - Liu, Weiping
AU - Yan, Yuelin
AU - Li, Jianping
AU - Yu, Changyuan
AU - Li, Zhaohui
N1 - Funding Information:
Manuscript received January 22, 2021; revised April 6, 2021 and April 14, 2021; accepted April 27, 2021. Date of publication April 30, 2021; date of current version July 16, 2021. This work was supported in part by the National Key R&D Program of China under Grant 2018YFB1802300, in part by the National Natural Science Foundation of China under Grants U2001601 and 62005102, in part by the Natural Science Foundation of Guangdong Province under Grant 2019A1515011059, in part by the Fundamental Research Funds for the Central Universities under Grant 21619309, and in part by the Open Fund of IPOC (BUPT) under Grant IPOC2019A001. (Corresponding authors: Ji Zhou; Chengkun Yang; Zhaohui Li.) Ji Zhou, Haide Wang, Shecheng Gao, Yuanhua Feng, and Weiping Liu are with the Department of Electronic Engineering, College of Information Science and Technology, Jinan University, Guangzhou 510632, China (e-mail: [email protected]; [email protected]; [email protected]; [email protected]; [email protected]).
Publisher Copyright:
© 1983-2012 IEEE.
PY - 2021/7/15
Y1 - 2021/7/15
N2 - In this paper, we present a field-trial C-band 72Gbit/s optical on-off keying (OOK) system over 18.8 km dispersion-uncompensated submarine optical cable in the South China Sea. Chromatic dispersion (CD) of 18.8 km submarine optical cable causes four spectral nulls on the 36 GHz bandwidth of 72Gbit/s OOK signal, which is the main obstacle for achieving an acceptable bit-error-rate (BER) performance. Decision feedback equalizer (DFE) is effective to compensate for the spectral nulls. However, DFE has a serious defect of burst-error propagation when the burst errors emerge due to the unstable submarine environment. Weighted DFE (WDFE) can be used to mitigate the burst-error propagation, but it cannot fully compensate for the spectral nulls because only a part of feedback symbols is directly decided. Fortunately, maximum likelihood sequence estimation (MLSE) can be added after the WDFE to simultaneously eliminate the residual spectral distortions and implement optimal detection. Compared to the joint DFE and MLSE algorithm, the joint WDFE and MLSE algorithm can effectively suppress the burst-error propagation to obtain a maximum 2.9 dB improvement of \boldsymbol{Q} factor and eliminate the phenomenon of BER floor. In conclusion, the joint WDFE and MLSE algorithm can solve the burst-error propagation for the field-trial fiber-optic communications.
AB - In this paper, we present a field-trial C-band 72Gbit/s optical on-off keying (OOK) system over 18.8 km dispersion-uncompensated submarine optical cable in the South China Sea. Chromatic dispersion (CD) of 18.8 km submarine optical cable causes four spectral nulls on the 36 GHz bandwidth of 72Gbit/s OOK signal, which is the main obstacle for achieving an acceptable bit-error-rate (BER) performance. Decision feedback equalizer (DFE) is effective to compensate for the spectral nulls. However, DFE has a serious defect of burst-error propagation when the burst errors emerge due to the unstable submarine environment. Weighted DFE (WDFE) can be used to mitigate the burst-error propagation, but it cannot fully compensate for the spectral nulls because only a part of feedback symbols is directly decided. Fortunately, maximum likelihood sequence estimation (MLSE) can be added after the WDFE to simultaneously eliminate the residual spectral distortions and implement optimal detection. Compared to the joint DFE and MLSE algorithm, the joint WDFE and MLSE algorithm can effectively suppress the burst-error propagation to obtain a maximum 2.9 dB improvement of \boldsymbol{Q} factor and eliminate the phenomenon of BER floor. In conclusion, the joint WDFE and MLSE algorithm can solve the burst-error propagation for the field-trial fiber-optic communications.
KW - burst-error propagation
KW - chromatic dispersion
KW - field-trial submarine fiber-optic communications
KW - Weighted decision-feedback equalizer
UR - http://www.scopus.com/inward/record.url?scp=85105072190&partnerID=8YFLogxK
U2 - 10.1109/JLT.2021.3076822
DO - 10.1109/JLT.2021.3076822
M3 - Journal article
AN - SCOPUS:85105072190
SN - 0733-8724
VL - 39
SP - 4601
EP - 4606
JO - Journal of Lightwave Technology
JF - Journal of Lightwave Technology
IS - 14
M1 - 9420243
ER -