skip to main content


Title: Intra-Data Center 120Gbaud/DP-16QAM Self-Homodyne Coherent Links with Simplified Coherent DSP
Abstract: The first 120Gbaud-based C-band self-homodyne 800Gb/s coherent links using low-latency FEC are experimentally demonstrated. A minimum coherent DSP is proposed to compensate fiber dispersion, phase mismatch between signal and local oscillator, and transceiver I-Q impairments.  more » « less
Award ID(s):
1821819
NSF-PAR ID:
10378728
Author(s) / Creator(s):
Date Published:
Journal Name:
2022 Optical Fiber Communications Conference and Exhibition (OFC)
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. We demonstrate efficient filtering of coherent light from a broad spectral background. A Michelson interferometer is used to effectively filter out the coherent emission of mid-infrared lasers from the co-propagating incoherent emission of a broadband thermal source. We show coherent light suppression as high as 16.9 dB without any modification of the broadband incoherent background spectrum. In addition, we demonstrate the ability to measure the spatially dependent (incoherent) thermal emission from a patterned surface, using our filter to remove a coherent signal which would otherwise overload our detection system. The demonstrated filter is rapidly tunable and wavelength-flexible, and has potential for imaging and spectroscopy applications in the presence of an otherwise overpowering coherent signal.

     
    more » « less
  2. Abstract: The first 120Gbaud-based C-band self-homodyne 800Gb/s coherent links using low-latency FEC are experimentally demonstrated. A minimum coherent DSP is proposed to compensate fiber dispersion, phase mismatch between signal and local oscillator, and transceiver I-Q impairments. 
    more » « less
  3. Abstract: The first 120Gbaud-based C-band self-homodyne 800Gb/s coherent links using lowlatency FEC are experimentally demonstrated. A minimum coherent DSP is proposed to compensate fiber dispersion, phase mismatch between signal and local oscillator, and transceiver I-Q impairments. © 2022 The Author(s) 
    more » « less
  4. We demonstrate a novel method for finding the coherent transfer matrix (CTM) of a multi-channel transmission medium utilizing backscattering and coherent optical time-domain reflectometry (COTDR). We measured the CTM for two polarizations of a single-mode fiber with ±0.3dB and ±8.5˚ amplitude and phase precisions 
    more » « less
  5. Abstract

    Mixing along isopycnals plays an important role in the transport and uptake of oceanic tracers. Isopycnal mixing is commonly quantified by a tracer diffusivity. Previous studies have estimated the tracer diffusivity using the rate of dispersion of surface drifters, subsurface floats, or numerical particles advected by satellite‐derived velocity fields. This study shows that the diffusivity can be more efficiently estimated from the dispersion of coherent mesoscale eddies. Coherent eddies are identified and tracked as the persistent sea surface height extrema in both a two‐layer quasigeostrophic (QG) model and an idealized primitive equation (PE) model. The Lagrangian diffusivity is estimated using the tracks of these coherent eddies and compared to the diagnosed Eulerian diffusivity. It is found that the meridional coherent eddy diffusivity approaches a stable value within about 20–40 days in both models. In the QG model, the coherent eddy diffusivity is a good approximation to the upper‐layer tracer diffusivity in a broad range of flow regimes, except for small values of bottom friction or planetary vorticity gradient, where the motions of same‐sign eddies are correlated over long distances. In the PE model, the tracer diffusivity has a complicated vertical structure and the coherent eddy diffusivity is correlated with the tracer diffusivity at the e‐folding depth of the energy‐containing eddies where the intrinsic speed of the coherent eddies matches the rms eddy velocity. These results suggest that the oceanic tracer diffusivity at depth can be estimated from the movements of coherent mesoscale eddies, which are routinely tracked from satellite observations.

     
    more » « less