Abstract

Data center interconnect (DCI) links with high data-rate direct-detection require strict chromatic dispersion compensation. One such solution which has been widely deployed is based on four-level pulse amplitude modulation (PAM4). With this application in mind, we describe in detail a 50-GHz channelized fiber Bragg grating (FBG) tunable dispersion compensation module (TDCM) which can compensate chromatic dispersion slope over the full C-band (4.8 THz) and is thus suitable for dense wavelength division multiplexing (DWDM) PAM4 DCI systems. We then present a comprehensive set of system performance results comprising 1,120 unique link measurements, to characterize the combined effect of statistical variations in component characteristics and link impairments, and show that a statistical approach to link budgeting is advantageous in this type of system. We also analyze the group delay ripple characteristics of the FBG-TDCM device and the corresponding impact on the PAM4 system. Instead of the conventional phase ripple standard deviation, we introduce a novel metric to quantify high-frequency phase ripple, which is better correlated with the impact on the PAM4 system.

Silicon Photonics-Based 100  Gbit/s, PAM4, DWDM Data Center Interconnects

Radhakrishnan Nagarajan, Mark Filer, Yang Fu, Masaki Kato, Todd Rope, and James Stewart
J. Opt. Commun. Netw. 10(7) B25-B36 (2018)

Amplifierless PAM-4/PAM-8 transmissions in O-band using a directly modulated laser for optical data-center interconnects

Nikolaos-Panteleimon Diamantopoulos, Wataru Kobayashi, Hidetaka Nishi, Koji Takeda, Takaaki Kakitsuka, and Shinji Matsuo
Opt. Lett. 44(1) 9-12 (2019)

Fiber Bragg gratings for pure dispersion-slope compensation

Morten Ibsen and Ricardo Feced
Opt. Lett. 28(12) 980-982 (2003)

100 Gb/s PAM4 transmission system for datacenter interconnects using a SiP ME-MZM based DAC-less transmitter and a VSB self-coherent receiver

Zhenping Xing, Alireza Samani, Meng Xiang, Eslam El-Fiky, Thang M. Hoang, David Patel, Rui Li, Meng Qiu, Md. Ghulam Saber, Mohamed Morsy-Osman, and David V. Plant
Opt. Express 26(18) 23969-23979 (2018)

Tunable dispersion slope compensator using two uniform fiber Bragg gratings mounted on S-shape plate

Sunduck Kim, Junkye Bae, Kwanil Lee, Sang Hyuck Kim, Je-Myung Jeong, and Sang Bae Lee
Opt. Express 17(6) 4336-4341 (2009)