Search

The International Football Association Board decided to introduce Video Assistant Referee (VAR) in 2018. This led to the need to develop methods for quality control of the VAR-systems. This article focuses on the important aspect to evaluate the video quality. Video Quality assessment has matured in the sense that there are standardized, commercial products and established open-source solutions to measure it with objective methods. Previous research has primarily focused on the end-user quality assessment. How to assess the video in the contribution phase of the chain is less studied. The novelties of this study are two-fold: 1) The user study is specifically targeting video experts i.e., to assess the perceived quality of video professionals working with video production. 2) Six video quality models have been independently benchmarked against the user data and evaluated to show which of the models could provide the best predictions of perceived quality. The independent evaluation is important to get unbiased results as shown by the Video Quality Experts Group. An experiment was performed involving 25 video experts in which they rated the perceived quality. The video formats tested were High-Definition TV both progressive and interlaced as well as a quarters size format that was scaled down half the size in both width and height. The videos were encoded with both H.264 and Motion JPEG for the full size but only H.264 for the quarter size. Bitrates ranged from 80 Mbit/s down to 10 Mbit/s. We could see that for H.264 that the quality was overall very good but dropped somewhat for 10 Mbit/s. For Motion JPEG the quality dropped over the whole range. For the interlaced format the degradation that was based on a simple deinterlacing method did receive overall low ratings. For the quarter size three different scaling algorithms were evaluated. Lanczos performed the best and Bilinear the worst. The performance of six different video quality models were evaluated for 1080p a

Changes in the footballing world’s approach to technology and innovation, along with major advancements in broadcasting contributed to the decision by the International Football Association Board to introduce Video Assistant Referees in 2018. The change meant that under strict protocols referees could use video replays to review decisions in the event of a “clear and obvious error” or a “serious missed incident”. At the time of writing 48-Member Associations have introduced the Video Assistant Referees protocol in at least one of their tournaments and there are many technology providers who work with organisers to implement the Video Assistant Referees systems. To ensure that the use of Video Assistant Referees has a positive effect on the game, Fédération Internationale de Football Association collaborated with the RISE Research Institutes of Sweden to develop objective test methods that could be used to ensure that a system can provide an adequate solution. Each provider must be able to pass requirements that ensure that they can deal with the challenges of processing, coding, decoding, synchronising, and re-formatting of the broadcast feeds. This article will describe the development of the test methods and illustrate some initial results from a test event on Video Assistant Referees system candidates. The methods have shown to be robust and appropriate for their intended purpose and will be developed over the years to ensure the quality of Video Assistant Referees. The developed measurement methods are general and can be applied to other broadcast and video systems as well as to other sports.

For coupled linear cavity-random fiber Raman lasers, for the first time, to the best of our knowledge, we demonstrate a new mechanism of emergence of the random pulses, with the anomalous statistics satisfying optical rogue waves’ criteria experimentally. The rogue waves appear as a result of the coupling of two Raman cascades, namely, a linear cavity laser with a wavelength of 1.55 µm and a random laser with a wavelength nearly 1.67 µm, along with coupling of the orthogonal states of polarization (SOPs). The coherent coupling of SOPs causes localization of the trajectories in the vicinity of these states, whereas polarization instability drives escape taking the form of chaotic oscillations. Antiphase dynamics in two cascades result in the suppression of low amplitude chaotic oscillations and enable the anomalous spikes, satisfying rogue waves criteria.

We present a theoretical and experimental investigation of unrepeatered transmission over standard single-mode fiber (SMF-28) using several schemes of distributed Raman amplification, including first, second, and dual order. In order to further extend the transmission distance, we utilize advanced bidirectional higher-order ultra-long Raman fiber laser-based amplification, where we use fiber Bragg gratings (FBGs) to reflect Stokes-shifted light from the secondary pumps. Our work demonstrates the possibility of transmission up to 240-km span length with a total span loss of 52.7 dB. Here, we use a 28-Gbaud signal using a 64-quadrature amplitude modulation (QAM) modulation format. Our results highlight the contribution of nonlinear compensation using digital back propagation in a digital signal processor (DSP) code at the receiver.

We propose a novel kernel affine projection (KAP) algorithm, which combines kernel mapping and affine projection for channel equalization in optical direct detection systems. Experimental results show that the KAP algorithm can mitigate nonlinear impairments in short-reach communications while maintaining low computational complexity., QC 20201126

By using a monolithically integrated dual-distributed feedback (DFB) laser chip attached to a photomixing uni-Travelling carrier photodiode (UTC-PD) with a THz antenna, single-channel THz photonic-wireless transmission system with a net rate of 131 Gbit/s over a wireless distance of 10.7 m has been achieved., Part of ISBN 9781728105970QC 20191021

© 2019 Optical Society of America. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modifications of the content of this paper are prohibited., [EN] We demonstrate 20-Gb/s 4-level pulse amplitude modulation (PAM-4) signal generation using a silicon Mach-Zehnder modulator (MZM) in the O-band. The modulator is driven by two independent binary streams. and the PAM-4 signal is thus generated directly on the chip, avoiding the use of power-hungry digital-to-analog converters (DACs). With optimized amplitude levels of the binary signals applied to the two arms of the MZM, a pre-forward error correction (FEC) bit-error rate (BER) as low as 7.6 x 10(-7) is obtained. In comparison with a commercially available LiNbO3 modulator, the penalty is only 2 dB at the KP4 FEC threshold of 2.2 x 10(-4).

We measure spontaneous Raman scattering (SRS) effects in C-band and observe trench-assisted MCF is robust to SRS noise, making it possible to run quantum channels in the neighboring and/or the same core as data channels.

A 107Gb/s net-rate DMT optical signal was generated using a single-mode long-wavelength VCSEL with a modulation bandwidth of 23 GHz. We experimentally demonstrated a total net-rate up to 726.7Gb/s at 1.5μm over 2.5km 7-core dispersion-uncompensated MCF. © 2018 OSA., QC 20181122

We experimentally demonstrate a 28-Gbaud circular and square 16/64QAM transmission over a 33.6-km long seven-core fiber with the LO passed through one of the cores for self-homodyne coherent detection employing a low-complexity digital signal processing., QC 20211020

This paper gives an overview of recent progress on the topic of using around 0.4 THz carriers for communications. Experimental demonstrations will be described, and concepts and pros & cons of various system-platforms discussed., SyskonpostNot duplicate with DiVA 1605706QC 20211020QC 20220302

We demonstrate 140 Gbaud intensity modulated direct detection dispersion-uncompensated links with Mach Zehnder modulator and distributed feedback travelling-wave electro-absorption modulator over 5500 and 960 meters of standard single mode fibre, respectively, enabled by compact packaged ultra-high speed InP-based 2:1-Selector., Part of proceedings ISBN 978-1-5386-4862-9QC 20200702

We investigate microring resonator (MRRs)-based optical spectral reshaping for directly-modulated 4-PAM signals. The phase-filtering of MRR, and consequent dispersion added to the signal, yields 120% reach increase compared to the 95% of amplitude-only filtering., QC 20211020

We demonstrate all-optical intensity modulation in integrated PMMA optical waveguides doped with silicon quantum dots. The 1550 nm probe signal is absorbed by free carriers excited in silicon quantum dots with 405 nm pump light., QC 20181025

We transmit 80 Gbaud/λ/core PAM4 signal enabled by 1.55 μm EML over 1 km 7-core fiber. The solution achieves single-wavelength and single-fiber 1.04 Tbit/s post-FEC transmission enhancing bandwidth-density for short-reach optical interconnects., QC 20181031

We summarize our recent research works on enabling coherent optical transmission systems for metro and access networks with low-complexity digital signal processing techniques, focusing on reduction of laser linewidth requirement with efficient carrier phase recovery., QC 20190917

We experimentally demonstrate the impact of inter-core crosstalk in multicore fibers on 56-Gbaud PAM-4 signal quality after 2.5-km transmission over a weakly-coupled and uncoupled seven-core fibers, revealing the crosstalk dependence on carrier central wavelength in range of 1540-1560 nm., QC20190816

We experimentally demonstrate a net-rate 503.61-Gbit/s discrete multitone (DMT) transmission over 10-km 7-core fiber with 1.5μm single mode VCSEL, where low-complexity kernel-recursive-least-squares algorithm is employed for nonlinear channel equalization., QC20190816

Kernel adaptive filtering (KAF) is proposed for nonlinearity-tolerant optical direct detection. for 7× 128 Gbit/s PAM4 transmission over 33.6km 7-core-fiber, KAF only needs 10 equalizer taps to reach KP4-FEC limit (BER@2.2e-4), whereas decision-feedback-equalizer needs 43 equalizer taps to reach HD-FEC limit (BER@3.8e-3)., Part of proceedings ISBN 978-1-5386-4862-9QC 20220923

A 107Gb/s net-rate DMT optical signal was generated using a single-mode long-wavelength VCSEL with a modulation bandwidth of 23GHz. We experimentally demonstrated a total net-rate up to 726.7Gb/s at 1.5 mu m over 2.5km 7-core dispersion-uncompensated MCF., QC 20180802

We experimentally characterize photon leakage from 112Gb/s data channels in both non-trench and trench-assistant 7-core fibers, demonstrating telecom compatibility for QKD co-existing with high-speed data transmission when a proper core/wavelength allocation is carried out., QC20190610

QC 20190502

100 Gbps/λ/core PAM-4 transmission is successfully demonstrated over 1-km and 10-km single mode 7-core fiber links, enabled by directly modulated 1.5-μm single mode VCSEL of 23 GHz modulation bandwidth with pre- and post-digital equalizations. © 2018 OSA., QC 20181128

In this letter, we introduce time domain hybrid quadrature amplitude modulation (TDHQ) for the single sideband discrete multi-tone systems. The experimental results reveal that with a single precoding set and the proposed adaptive loading algorithm, the TDHQ scheme can achieve finer granularity and therefore smoother continuous growth of data rate than that with the conventional quadrature amplitude modulation. Besides, thanks to the frame construction and the tailored mapping rule, the scheme with TDHQ has an obviously better peak to an average power ratio., Export Date: 22 October 2018; Article; CODEN: IPTLE; Correspondence Address: Tang, M.; Wuhan National Laboratory for Optoelectronics, National Engineering Laboratory for Next Generation Internet Access System, School of Optical and Electronic Information, Huazhong University of Science and TechnologyChina; email: tangming@hust.edu.cn; Funding details: VR, Vetenskapsrådet; Funding details: Göran Gustafssons Stiftelse för Naturvetenskaplig och Medicinsk Forskning; Funding details: VINNOVA; Funding details: SSF, Stiftelsen för Strategisk Forskning; Funding details: 61722108, NSFC, National Natural Science Foundation of China; Funding details: 61331010, NSFC, National Natural Science Foundation of China; Funding details: SSF, Sjögren’s Syndrome Foundation; Funding details: visa0524@163.com;, HUST, Huazhong University of Science and Technology; Funding details: WNLO, Wuhan National Laboratory for Optoelectronics; Funding details: NSFC, National Natural Science Foundation of China; Funding text: Manuscript received June 29, 2018; revised August 11, 2018; accepted August 17, 2018. Date of publication August 21, 2018; date of current version September 5, 2018. This work was supported in part by the National Natural Science Foundation of China (NSFC) under Grant 61331010 and Grant 61722108, in part by the Swedish Research Council (VR), in part by the Swedish Foundation for Strategic Research (SSF), in part by Göran Gustafsson Foundation, in part by the Swedish SRA ICT-TNG, VINNOVA SENDATE-FICUS, and SENDATE-EXTEND Projects. (Corresponding author: Ming Tang.) X. Chen, J. Cui, L. Gan, T. Jiang, M. Tang, S. Fu, and D. Liu are with the Wuhan National Laboratory for Optoelectronics and the National Engineering Laboratory for Next Generation Internet Access System, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China (e-mail: hust_chenxi@ hust.edu.cn; jingxian@hust.edu.cn; lingan@hust.edu.cn; visa0524@163.com; tangming

A BiCMOS chip-based real-time IM/DD spatial division multiplexing system is experimentally demonstrated for short-reach communications. 100 Gbps/λ/core NRZ and EDB transmission is achieved below 7%-overhead HD-FEC limit after 10km 7-core fiber with optical dispersion compensation., QC 20181106

We demonstrate 56 Gbaud/λ PAM4 inter - data center interconnects over 81 km single core single mode fiber and 33.6 km 7-core single mode fiber with continuous-fiber Bragg grating based chromatic dispersion compensators covering C-band., QC 20181025

We report on our recent work in supporting up to 100 Gbps/λ/core transmissions with a directly modulated 1.5-μm single mode VCSEL and multicore fiber, enabled by low-compleixty pre- and post- digital equalizations., QC 20181022

By employing enhanced DPCM, 15-Gbaud PAM4 digital mobile fronthaul is experimentally demonstrated to support 122 LTE-A channels with up to 4096QAM. Compared to PCM based CPRI, the supported number of channels increases 5 times and EVM is obviously improved., QC 20180528

Integrated polymer photonics brings low cost and high fabrication flexibility to optoelectronic industry. However, this platform needs to overcome several issues to be effective enough for practical applications. In this letter, we experimentally demonstrate a decrease of propagation losses and polarization sensitivity of polymer waveguide-based devices as a result of thermal treatment. Heating of poly(methyl methacrylate) strip optical waveguides above the glass transition temperature initiates a waveguide surface reflow due to a decrease of the polymer viscosity and surface tension energy. This results in a decrease of surface roughness and shape change from rectangular to cylindrical. Thus, scattering losses and polarization sensitivity are minimized., Export Date: 9 May 2018; Article; CODEN: IPTLE; Correspondence Address: Marinins, A.; School of Engineering Sciences, KTH Royal Institute of TechnologySweden; email: marinin@kth.se; Funding details: 608099; Funding details: SEAS, Harvard School of Engineering and Applied Sciences; Funding details: 324391; Funding details: 2016-04510; Funding details: Knut och Alice Wallenbergs Stiftelse; Funding details: KTH, Kungliga Tekniska Högskolan; Funding text: Manuscript received March 14, 2017; revised January 21, 2018; accepted January 22, 2018. Date of publication January 24, 2018; date of current version February 12, 2018. This work was supported in part by EU Project ICONE under Grant 608099, in part by the EU Project GRIFFON under Grant 324391, in part by the Swedish ICT-TNG Program, in part by the Vetenskapsrädet Project PHASE under Grant 2016-04510, and in part by the Knut and Alice Wallenberg Foundation. (Corresponding author: Aleksandrs Marinins.) A. Marinins, A. Kakkar, R. Schatz, and S. Popov are with the School of Engineering Sciences, KTH Royal Institute of Technology, 10044 Stockholm, Sweden (e-mail: marinin@kth.se; adityak@kth.se; rschatz@kth.se; sergeip@kth.se). QC 20180529

We demonstrate an on-offkeyed transmitter with direct detection, at record symbol rates of 204Gbaud and 140Gbaud, over 10km and 80km, respectively, powered by a high-speed InPbased 2:1 selector and travelling-wave electro-absorption laser-modulator., QC 20180529

We propose to group highly-correlated neighboring samples into multi-dimensional vectors and adopt k-means clustering for quantization in mobile fronthaul. 30-Gbit/s transmissions have been experimentally demonstrated for up to 40 100MHz LTE channels over 20km fiber., Part of proceedings: ISBN 978-1-55752-820-9SyskonpostNot duplicate with DiVA 1236395QC 20180529

A BiCMOS chip-based real-time intensity modulation/direct detection spatial division multiplexing system is experimentally demonstrated for both optical interconnects. 100 Gbps/λ/core electrical duobinary (EDB) transmission over 1 km 7-core multicore fiber (MCF) is carried out, achieving KP4 forward error correction (FEC) limit (BER < 2E-4). Using optical dispersion compensation, 7 × 100 Gbps/λ/core transmission of both non-return-to-zero (NRZ) and EDB signals over 10 km MCF transmission is achieved with BER lower than 7% overhead hard-decision FEC limit (BER < 3.8E-3). The integrated low complexity transceiver IC and analog signal processing approach make such a system highly attractive for the high-speed intra-datacenter interconnects., QC 20180518