TY - JOUR
T1 - Intelligent 2-Dimensional Soft Decision Enabled by K-Means Clustering for VCSEL-Based 112-Gbps PAM-4 and PAM-8 Optical Interconnection
AU - Sun, Lin
AU - Du, Jiangbing
AU - Liu, Jiacheng
AU - Chen, Bin
AU - Xu, Ke
AU - Liu, Bo
AU - Lu, Chao
AU - He, Zuyuan
N1 - Funding Information:
Manuscript received August 6, 2019; revised September 30, 2019; accepted October 4, 2019. Date of publication October 11, 2019; date of current version December 10, 2019. This work was supported in part by the National Natural Science Foundation of China (NSFC) under Grant 61935011, Grant 61701155, Grant 61875124, Grant 61875049, and Grant 61675128, in part by the National Key R&D Program of China under Grant 2018YFB1801804, and in part by Shenzhen Science and Technology Innovation Commission under Grants JCYJ20180507183418012 and KQJSCX20180328165451777. (Corresponding author: Jiangbing Du.) L. Sun is with the State Key Laboratory of Advanced Optical Communication Systems and Networks, Department of Electronic Engineering, Shanghai Jiao Tong University, Shanghai 200240, China and also with the Hong Kong Polytechnic University, Hong Kong (e-mail: [email protected]).
Funding Information:
This work was supported in part by the National Natural Science Foundation of China (NSFC) under Grant 61935011, Grant 61701155, Grant 61875124, Grant 61875049, and Grant 61675128, in part by the National Key R&D Program of China under Grant 2018YFB1801804, and in part by Shenzhen Science and Technology Innovation Commission under Grants JCYJ20180507183418012 and KQJSCX20180328165451777.
Publisher Copyright:
© 1983-2012 IEEE.
PY - 2019/12/15
Y1 - 2019/12/15
N2 - In this work, we proposed an intelligent 2-dimensional soft decision (2D SD) enabled by k-means clustering, for vertical-cavity surface-emitting laser (VCSEL) based 112-Gbps PAM-4 and PAM-8 optical interconnection. At high modulation speed, VCSEL based link suffers from severe level nonlinearity, level-dependent noise and inter-symbol interference (ISI). For characterizing the above-mentioned three distortions, 2D signaling is performed through time-slotted mapping of PAM. Without extra requirement of Monte Carlo approach, channel conditional probability density function (PDF) can be intelligently estimated using inline data, thanks to 2D k-means machine learning. Thus, improved precision of log likelihood ratio (LLR) can be realized by additional consideration of nonlinearity, level-dependent noise and ISI. Both simulations and experiments have been carried out for proof-of-concept investigations on VCSEL and multimode fiber (MMF) links. 112-Gbps PAM-4 and PAM-8 signaling have been experimentally realized using a commercial-product-level VCSEL with 100-m MMF transmission. The results indicate significant improvement of the proposed k-means 2D SD without training using prior-known sequences.
AB - In this work, we proposed an intelligent 2-dimensional soft decision (2D SD) enabled by k-means clustering, for vertical-cavity surface-emitting laser (VCSEL) based 112-Gbps PAM-4 and PAM-8 optical interconnection. At high modulation speed, VCSEL based link suffers from severe level nonlinearity, level-dependent noise and inter-symbol interference (ISI). For characterizing the above-mentioned three distortions, 2D signaling is performed through time-slotted mapping of PAM. Without extra requirement of Monte Carlo approach, channel conditional probability density function (PDF) can be intelligently estimated using inline data, thanks to 2D k-means machine learning. Thus, improved precision of log likelihood ratio (LLR) can be realized by additional consideration of nonlinearity, level-dependent noise and ISI. Both simulations and experiments have been carried out for proof-of-concept investigations on VCSEL and multimode fiber (MMF) links. 112-Gbps PAM-4 and PAM-8 signaling have been experimentally realized using a commercial-product-level VCSEL with 100-m MMF transmission. The results indicate significant improvement of the proposed k-means 2D SD without training using prior-known sequences.
KW - Decision support systems
KW - machine learning
KW - multidimensional signal processing
KW - optical fiber communication
UR - http://www.scopus.com/inward/record.url?scp=85076977584&partnerID=8YFLogxK
U2 - 10.1109/JLT.2019.2946920
DO - 10.1109/JLT.2019.2946920
M3 - Journal article
AN - SCOPUS:85076977584
SN - 0733-8724
VL - 37
SP - 6133
EP - 6146
JO - Journal of Lightwave Technology
JF - Journal of Lightwave Technology
IS - 24
M1 - 8865090
ER -