1,073 research outputs found
Harnessing machine learning for fiber-induced nonlinearity mitigation in long-haul coherent optical OFDM
© 2018 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).Coherent optical orthogonal frequency division multiplexing (CO-OFDM) has attracted a lot of interest in optical fiber communications due to its simplified digital signal processing (DSP) units, high spectral-efficiency, flexibility, and tolerance to linear impairments. However, CO-OFDM’s high peak-to-average power ratio imposes high vulnerability to fiber-induced non-linearities. DSP-based machine learning has been considered as a promising approach for fiber non-linearity compensation without sacrificing computational complexity. In this paper, we review the existing machine learning approaches for CO-OFDM in a common framework and review the progress in this area with a focus on practical aspects and comparison with benchmark DSP solutions.Peer reviewe
Principles of Neuromorphic Photonics
In an age overrun with information, the ability to process reams of data has
become crucial. The demand for data will continue to grow as smart gadgets
multiply and become increasingly integrated into our daily lives.
Next-generation industries in artificial intelligence services and
high-performance computing are so far supported by microelectronic platforms.
These data-intensive enterprises rely on continual improvements in hardware.
Their prospects are running up against a stark reality: conventional
one-size-fits-all solutions offered by digital electronics can no longer
satisfy this need, as Moore's law (exponential hardware scaling),
interconnection density, and the von Neumann architecture reach their limits.
With its superior speed and reconfigurability, analog photonics can provide
some relief to these problems; however, complex applications of analog
photonics have remained largely unexplored due to the absence of a robust
photonic integration industry. Recently, the landscape for
commercially-manufacturable photonic chips has been changing rapidly and now
promises to achieve economies of scale previously enjoyed solely by
microelectronics.
The scientific community has set out to build bridges between the domains of
photonic device physics and neural networks, giving rise to the field of
\emph{neuromorphic photonics}. This article reviews the recent progress in
integrated neuromorphic photonics. We provide an overview of neuromorphic
computing, discuss the associated technology (microelectronic and photonic)
platforms and compare their metric performance. We discuss photonic neural
network approaches and challenges for integrated neuromorphic photonic
processors while providing an in-depth description of photonic neurons and a
candidate interconnection architecture. We conclude with a future outlook of
neuro-inspired photonic processing.Comment: 28 pages, 19 figure
Intelligent Multi-channel Meta-imagers for Accelerating Machine Vision
Rapid developments in machine vision have led to advances in a variety of
industries, from medical image analysis to autonomous systems. These
achievements, however, typically necessitate digital neural networks with heavy
computational requirements, which are limited by high energy consumption and
further hinder real-time decision-making when computation resources are not
accessible. Here, we demonstrate an intelligent meta-imager that is designed to
work in concert with a digital back-end to off-load computationally expensive
convolution operations into high-speed and low-power optics. In this
architecture, metasurfaces enable both angle and polarization multiplexing to
create multiple information channels that perform positive and negatively
valued convolution operations in a single shot. The meta-imager is employed for
object classification, experimentally achieving 98.6% accurate classification
of handwritten digits and 88.8% accuracy in classifying fashion images. With
compactness, high speed, and low power consumption, this approach could find a
wide range of applications in artificial intelligence and machine vision
applications.Comment: 15 pages, 5 figure
Photon temporal modes: a complete framework for quantum information science
Field-orthogonal temporal modes of photonic quantum states provide a new
framework for quantum information science (QIS). They intrinsically span a
high-dimensional Hilbert space and lend themselves to integration into existing
single-mode fiber communication networks. We show that the three main
requirements to construct a valid framework for QIS -- the controlled
generation of resource states, the targeted and highly efficient manipulation
of temporal modes and their efficient detection -- can be fulfilled with
current technology. We suggest implementations of diverse QIS applications
based on this complete set of building blocks.Comment: 17 pages, 13 figure
Optoelectronic Key Elements for Polymeric Fiber Transmission Systems
In short-range communication 1 mm PMMA SI-POF established itself as a reasonable alternative to the traditional data communication media such as glass fibers, copper cables, and wireless systems. Due to multiple advantages such as a large core diameter, tolerance to fiber facet damages, and low installation costs, the SI-POF is already applied in industrial automation, automotive industry, and in-house/office networks. To experimentally demonstrate the feasibility and potential of a high-speed POF WDM concept, a four-channel data transmission setup was realized. A four-legged multiplexing POF bundle was developed to combine the signals from four visible laser diodes onto SI-POF link. For the separation of wavelength channels, the interference filter-based demultiplexer with two-stage configuration was used. It was shown that POF WDM with lower channel rates and simple transmission technique (NRZ + FFE) could provide aggregate bit rates comparable to those achieved with the single-wavelength systems that used advanced modulation formats (DMT or PAM + DFE) and required significant signal processing. In addition, the 50 m SI-POF link at an aggregate bit rate of 7.8 Gb/s was demonstrated over 50 m SI-POF, respectively, at the BER = 10–3
SCONNA: A Stochastic Computing Based Optical Accelerator for Ultra-Fast, Energy-Efficient Inference of Integer-Quantized CNNs
The acceleration of a CNN inference task uses convolution operations that are
typically transformed into vector-dot-product (VDP) operations. Several
photonic microring resonators (MRRs) based hardware architectures have been
proposed to accelerate integer-quantized CNNs with remarkably higher throughput
and energy efficiency compared to their electronic counterparts. However, the
existing photonic MRR-based analog accelerators exhibit a very strong trade-off
between the achievable input/weight precision and VDP operation size, which
severely restricts their achievable VDP operation size for the quantized
input/weight precision of 4 bits and higher. The restricted VDP operation size
ultimately suppresses computing throughput to severely diminish the achievable
performance benefits. To address this shortcoming, we for the first time
present a merger of stochastic computing and MRR-based CNN accelerators. To
leverage the innate precision flexibility of stochastic computing, we invent an
MRR-based optical stochastic multiplier (OSM). We employ multiple OSMs in a
cascaded manner using dense wavelength division multiplexing, to forge a novel
Stochastic Computing based Optical Neural Network Accelerator (SCONNA). SCONNA
achieves significantly high throughput and energy efficiency for accelerating
inferences of high-precision quantized CNNs. Our evaluation for the inference
of four modern CNNs at 8-bit input/weight precision indicates that SCONNA
provides improvements of up to 66.5x, 90x, and 91x in frames-per-second (FPS),
FPS/W and FPS/W/mm2, respectively, on average over two photonic MRR-based
analog CNN accelerators from prior work, with Top-1 accuracy drop of only up to
0.4% for large CNNs and up to 1.5% for small CNNs. We developed a
transaction-level, event-driven python-based simulator for the evaluation of
SCONNA and other accelerators (https://github.com/uky-UCAT/SC_ONN_SIM.git).Comment: To Appear at IPDPS 202
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