Advanced search
2 files | 8.68 MB

Real-Time and DSP-Free 128 Gb/s PAM-4 Link Using a Binary Driven Silicon Photonic Transmitter

Jochem Verbist (UGent) , Joris Lambrecht (UGent) , Michiel Verplaetse (UGent) , Srinivasan Ashwyn Srinivasan (UGent) , Peter De Heyn (UGent) , Timothy De Keulenaer (UGent) , Ramses Pierco (UGent) , Arno Vyncke (UGent) , Joris Van Campenhout, Xin Yin (UGent) , et al.
Author
Organization
Abstract
Optical transmitters for four-level pulse amplitude modulation (PAM-4) have attracted a significant amount of research in recent years, in large part due to the standardization of the format for the 200 and 400 Gigabit Ethernet optical interconnects in data centers. However, combining low-power and linear operation of the electro-optical frontend with sufficiently large bandwidths has proven challenging, especially for the 100 Gb/s/lambda links (i.e., employing 50 Gbaud PAM-4). The most straightforward solution has been to deal with the non-idealities of the modulator in the electrical domain: predistorting the signal levels and/or equalizing the frequency response with the help of digital signal processing (DSP). However, this typically requires fast digital-to-analog converters (DACs), either capable of delivering large swings (>1 Vpp) or supplemented with an additional linear amplifier to drive the optical modulator. Both options substantially increase the power consumption and the complexity of the transceiver. Rather than allocating effort to linearize the electrical to optical conversion of a single modulator, we propose a topology that performs the DAC operation in the optical domain. Two compact electro-absorption modulators in an interferometer layout are driven with NRZ data to generate the four-level signal in the optical domain. Using this topology, we demonstrate the first real-time 128 Gb/s PAM-4 transmission with a silicon photonic transmitter in a chip-to-chip link. In a back-to-back setup, we obtained a bit-error ratio (BER) of 4 x 10(-10) without requiring any DAC, DSP, or modulators with large traveling wave structures. Over 1 km of standard single mode fiber a BER of 8 x 10(-6) is recorded, still well below the KP4 forward error-coding limit. These results correspond to the lowest BERs reported for any real-time PAM-4 link at 100 Gb/s or higher, illustrating the benefit of performing the DAC operation in the optical domain.
Keywords
TRANSMISSION, MODULATOR, NRZ, Pulse amplitude modulation (PAM-4), short-reach interconnects, silicon, photonics

Downloads

  • (...).pdf
    • full text
    • |
    • UGent only
    • |
    • PDF
    • |
    • 3.33 MB
  • 7397 i.pdf
    • full text
    • |
    • open access
    • |
    • PDF
    • |
    • 5.35 MB

Citation

Please use this url to cite or link to this publication:

Chicago
Verbist, Jochem, Joris Lambrecht, Michiel Verplaetse, Srinivasan Ashwyn Srinivasan, Peter De Heyn, Timothy De Keulenaer, Ramses Pierco, et al. 2019. “Real-Time and DSP-Free 128 Gb/s PAM-4 Link Using a Binary Driven Silicon Photonic Transmitter.” Journal of Lightwave Technology 37 (2): 274–280.
APA
Verbist, J., Lambrecht, J., Verplaetse, M., Srinivasan, S. A., De Heyn, P., De Keulenaer, T., Pierco, R., et al. (2019). Real-Time and DSP-Free 128 Gb/s PAM-4 Link Using a Binary Driven Silicon Photonic Transmitter. JOURNAL OF LIGHTWAVE TECHNOLOGY, 37(2), 274–280. Presented at the Optical Fiber Communications Conference and Exposition (OFC).
Vancouver
1.
Verbist J, Lambrecht J, Verplaetse M, Srinivasan SA, De Heyn P, De Keulenaer T, et al. Real-Time and DSP-Free 128 Gb/s PAM-4 Link Using a Binary Driven Silicon Photonic Transmitter. JOURNAL OF LIGHTWAVE TECHNOLOGY. Piscataway: Ieee-inst Electrical Electronics Engineers Inc; 2019;37(2):274–80.
MLA
Verbist, Jochem et al. “Real-Time and DSP-Free 128 Gb/s PAM-4 Link Using a Binary Driven Silicon Photonic Transmitter.” JOURNAL OF LIGHTWAVE TECHNOLOGY 37.2 (2019): 274–280. Print.
@article{8607518,
  abstract     = {Optical transmitters for four-level pulse amplitude modulation (PAM-4) have attracted a significant amount of research in recent years, in large part due to the standardization of the format for the 200 and 400 Gigabit Ethernet optical interconnects in data centers. However, combining low-power and linear operation of the electro-optical frontend with sufficiently large bandwidths has proven challenging, especially for the 100 Gb/s/lambda links (i.e., employing 50 Gbaud PAM-4). The most straightforward solution has been to deal with the non-idealities of the modulator in the electrical domain: predistorting the signal levels and/or equalizing the frequency response with the help of digital signal processing (DSP). However, this typically requires fast digital-to-analog converters (DACs), either capable of delivering large swings ({\textrangle}1 Vpp) or supplemented with an additional linear amplifier to drive the optical modulator. Both options substantially increase the power consumption and the complexity of the transceiver. Rather than allocating effort to linearize the electrical to optical conversion of a single modulator, we propose a topology that performs the DAC operation in the optical domain. Two compact electro-absorption modulators in an interferometer layout are driven with NRZ data to generate the four-level signal in the optical domain. Using this topology, we demonstrate the first real-time 128 Gb/s PAM-4 transmission with a silicon photonic transmitter in a chip-to-chip link. In a back-to-back setup, we obtained a bit-error ratio (BER) of 4 x 10(-10) without requiring any DAC, DSP, or modulators with large traveling wave structures. Over 1 km of standard single mode fiber a BER of 8 x 10(-6) is recorded, still well below the KP4 forward error-coding limit. These results correspond to the lowest BERs reported for any real-time PAM-4 link at 100 Gb/s or higher, illustrating the benefit of performing the DAC operation in the optical domain.},
  author       = {Verbist, Jochem and Lambrecht, Joris and Verplaetse, Michiel and Srinivasan, Srinivasan Ashwyn and De Heyn, Peter and De Keulenaer, Timothy and Pierco, Ramses and Vyncke, Arno and Van Campenhout, Joris and Yin, Xin and Bauwelinck, Johan and Torfs, Guy and Roelkens, G{\"u}nther},
  issn         = {0733-8724},
  journal      = {JOURNAL OF LIGHTWAVE TECHNOLOGY},
  language     = {eng},
  location     = {San Diego, CA},
  number       = {2},
  pages        = {274--280},
  publisher    = {Ieee-inst Electrical Electronics Engineers Inc},
  title        = {Real-Time and DSP-Free 128 Gb/s PAM-4 Link Using a Binary Driven Silicon Photonic Transmitter},
  url          = {http://dx.doi.org/10.1109/JLT.2018.2877461},
  volume       = {37},
  year         = {2019},
}

Altmetric
View in Altmetric
Web of Science
Times cited: