The Experts below are selected from a list of 18132 Experts worldwide ranked by ideXlab platform
Ahmed Nabih Zaki Rashed - One of the best experts on this subject based on the ideXlab platform.
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Modern Fiber Optic Submarine Cable Telecommunication Systems Planning for Explosive Bandwidth Needs at Different Deployment Depths.
International Journal of Advanced Networking & Applications, 2012Co-Authors: Ahmed Nabih Zaki RashedAbstract:The explosive bandwidth needs, especially in the inter data center market, have pushed transmission data rates to 100 GBit/sec and beyond. Current terrestrial fibers are inadequate for long haul, high bandwidth deployments. To solve these problems a new fiber is introduced for terrestrial high bandwidth deployments: different polymeric core fibers with enlarged effective area with a significant optical signal to noise ratio improvement over other conventional terrestrial single mode fibers. To ensure the new fiber may be deployed robustly a new coating structure was employed. A rigorous cable structure was then chosen for evaluation. Based on experimental data, both the deep ocean water temperature and pressure are tailored as functions of the water depth. As well as the product of the Transmitted Bit rate and the repeater spacing is processed over wide ranges of the affecting parameters. It is taken into account the estimation of the total cost of the submarine fiber cable system for transmission technique under considerations. The system capacity as well as the spectral losses, and the dispersion effects are parametrically investigated over wide range ranges of the set of affecting parameters {wavelength, ocean depth (and consequently the ocean pressure and temperature), and the chemical structure}. [ABSTRACT FROM AUTHOR]
C C J Kuo - One of the best experts on this subject based on the ideXlab platform.
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robust streaming of offline coded h 264 avc video via alternative macroblock coding
IEEE Transactions on Circuits and Systems for Video Technology, 2008Co-Authors: Xiaosong Zhou, C C J KuoAbstract:An error resilient video streaming scheme that transmits offline coded H.264/AVC video through erroneous channels, called the alternative macroblock coding (AMC) scheme, is proposed in this work. In the AMC scheme, each macroblock can be reconstructed from one default and several alternative versions coded using different predictions. During the transmission, the sender tracks ACK or NACK messages from the receiver to detect transmission errors. When the reference used in the default version of a macroblock that has not been Transmitted is corrupted by errors, one of its alternative versions that has the correctly received reference is selected to replace the default version in the output Bit stream to stop error propagation. The AMC scheme is designed to ensure that the Bit stream replacement during streaming will not cause significant mismatch at the decoder end and neither introduce large Bit rate overhead to the Transmitted Bit stream. Furthermore, adaptive quantization selection and Bit stream replacement methods are developed to improve the rate-distortion performance of received video. It is demonstrated by experimental results that the AMC scheme is effective in reducing error propagation in offline coded H.264/AVC video.
Xiaosong Zhou - One of the best experts on this subject based on the ideXlab platform.
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Robust Streaming of Offline Coded H.264/AVC Video Via Alternative Macroblock Coding
2016Co-Authors: Xiaosong Zhou, -c. Jay C. KuoAbstract:Abstract—An error resilient video streaming scheme that trans-mits offline coded H.264/AVC video through erroneous channels, called the alternative macroblock coding (AMC) scheme, is pro-posed in this work. In the AMC scheme, each macroblock can be reconstructed from one default and several alternative versions coded using different predictions. During the transmission, the sender tracks ACK or NACK messages from the receiver to detect transmission errors. When the reference used in the default ver-sion of a macroblock that has not been Transmitted is corrupted by errors, one of its alternative versions that has the correctly received reference is selected to replace the default version in the output Bit stream to stop error propagation. The AMC scheme is designed to ensure that the Bit stream replacement during streaming will not cause significant mismatch at the decoder end and neither introduce large Bit rate overhead to the Transmitted Bit stream. Furthermore, adaptive quantization selection and Bit stream replacement methods are developed to improve the rate-distortion performance of received video. It is demonstrated by experimental results that the AMC scheme is effective in reducing error propagation in offline coded H.264/AVC video. Index Terms—AVC, error resilience, H.264, video coding, video streaming. I
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robust streaming of offline coded h 264 avc video via alternative macroblock coding
IEEE Transactions on Circuits and Systems for Video Technology, 2008Co-Authors: Xiaosong Zhou, C C J KuoAbstract:An error resilient video streaming scheme that transmits offline coded H.264/AVC video through erroneous channels, called the alternative macroblock coding (AMC) scheme, is proposed in this work. In the AMC scheme, each macroblock can be reconstructed from one default and several alternative versions coded using different predictions. During the transmission, the sender tracks ACK or NACK messages from the receiver to detect transmission errors. When the reference used in the default version of a macroblock that has not been Transmitted is corrupted by errors, one of its alternative versions that has the correctly received reference is selected to replace the default version in the output Bit stream to stop error propagation. The AMC scheme is designed to ensure that the Bit stream replacement during streaming will not cause significant mismatch at the decoder end and neither introduce large Bit rate overhead to the Transmitted Bit stream. Furthermore, adaptive quantization selection and Bit stream replacement methods are developed to improve the rate-distortion performance of received video. It is demonstrated by experimental results that the AMC scheme is effective in reducing error propagation in offline coded H.264/AVC video.
Norbert Hanik - One of the best experts on this subject based on the ideXlab platform.
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Long-haul transmission of PM-16QAM-, PM-32QAM-, and PM-64QAM-based teraBit superchannels over a field deployed legacy fiber
Journal of Lightwave Technology, 2016Co-Authors: Talha Rahman, Celine Andre, Erwan Pincemin, Bernhard Spinnler, Danish Rafique, Chigo M. Okonkwo, Uwe Feiste, Stefano Calabro, A.m.j. Koonen, Ginni Khanna, Marc Bohn, Bruno Raguenes, Norbert Hanik, Jérémie Jauffrit, Christian Dourthe, Martin Bohn, Claude Le Bouëtté, Sylvain Bordais, Erik De Man, Antonio Napoli, Huug de de WaardtAbstract:Increase in transmission symbol-rate as well as order of quadrature amplitude modulation (QAM) is identified as the most economical way to reduce cost per Transmitted Bit. In particular, next generation transponders aim at supporting data-rates up to 1 Tb/s employing superchannels due to electrical components� bandwidth limitations. Furthermore, the introduction of a flexible-grid architecture can maximize throughput by minimizing spectral gaps in available optical spectrum. Keeping in view these design options, we conducted several high capacity experiments with tier1 operator Orange using their field deployed standard single mode fiber (SSMF, G.652), having a total length of 762 km, connecting the cities Lyon and Marseille in France. In particular we employed four subcarriers per Tb/s superchannel, each modulated by PM-16QAM, PM-32QAM, and PM-64QAM with per carrier symbol-rates of 41.2 GBd, 33 GBd, and 34 GBd, respectively. The subcarrier spacing was 50 GHz for the PM-16QAM case and 37.5 GHz for both the PM-32QAM and PM-64QAM cases allowing in total 24 \times 1.0, 32 \times 1.0, and 32 \times 1.2 Tb/s superchannels over C-band and resulting in potential C-band capacities of 24.0, 32.0, and 38.4 Tb/s, respectively. After field transmission the maximum available \rm {OSNR_{0.1,nm}} margin compared to the required \rm {OSNR_{0.1,nm}} at forward error correction (FEC) threshold was 8.2, 5.4, and 4.2 dB for PM-16QAM, PM-32QAM, and PM-64QAM, respectively. The transmission reach for PM-16QAM and PM-32QAM modulated superchannels was- extended to ~1571 and ~1065 km using erbium doped fiber amplified SSMF spans of ~101 km length.
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Reduced Complexity Digital Back-Propagation Methods for Optical Communication Systems
Journal of Lightwave Technology, 2014Co-Authors: Antonio Napoli, Leonardo Didier Coelho, Erik Timmers, Vincent A J M Sleiffer, Zied Maalej, Maxim Kuschnerov, Talha Rahman, Danish Rafique, Bernhard Spinnler, Norbert HanikAbstract:Next-generation optical communication systems will continue to push the ( bandwidth · distance) product towards its physical limit. To address this enormous demand, the usage of digital signal processing together with advanced modulation formats and coherent detection has been proposed to enable data-rates as high as 400 Gb/s per channel over distances in the order of 1000 km. These technological breakthroughs have been made possible by full compensation of linear fiber impairments using digital equalization algorithms. While linear equalization techniques have already matured over the last decade, the next logical focus is to explore solutions enabling the mitigation of the Kerr effect induced nonlinear channel impairments. One of the most promising methods to compensate for fiber nonlinearities is digital back-propagation (DBP), which has recently been acknowledged as a universal compensator for fiber propagation impairments, albeit with high computational requirements. In this paper, we discuss two proposals to reduce the hardware complexity required by DBP. The first confirms and extends published results for non-dispersion managed link, while the second introduces a novel method applicable to dispersion managed links, showing complexity reductions in the order of 50% and up to 85%, respectively. The proposed techniques are validated by comparing results obtained through post-processing of simulated and experimental data, employing single channel and WDM configurations, with advanced modulation formats, such as quadrature phase shift keying (QPSK) and 16-ary quadrature amplitude modulation (16-QAM). The considered net symbol rate for all cases is 25 GSymbol/s. Our post-processing results show that we can significantly reduce the hardware complexity without affecting the system performance. Finally, a detailed analysis of the obtained reduction is presented for the case of dispersion managed link in terms of number of required complex multiplications per- Transmitted Bit.
Key Words - One of the best experts on this subject based on the ideXlab platform.
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Modern Fiber Optic Submarine Cable Telecommunication Systems Planning for Explosive Bandwidth Needs at Different Deployment Depths
2012Co-Authors: Ahmed Nabih, Zaki Rashed, Key WordsAbstract:Polymeric cable material, Giga Bit applications, Explosive bandwidth, Effective area, and Global communications The explosive bandwidth needs, especially in the inter data center market, have pushed transmission data rates to 100 GBit/sec and beyond. Current terrestrial fibers are inadequate for long haul, high bandwidth deployments. To solve these problems a new fiber is introduced for terrestrial high bandwidth deployments: different polymeric core fibers with enlarged effective area with a significant optical signal to noise ratio improvement over other conventional terrestrial single mode fibers. To ensure the new fiber may be deployed robustly a new coating structure was employed. A rigorous cable structure was then chosen for evaluation. Based on experimental data, both the deep ocean water temperature and pressure are tailored as functions of the water depth. As well as the product of the Transmitted Bit rate and the repeater spacing is processed over wide ranges of the affecting parameters. It is taken into account the estimation of the total cost of the submarine fiber cable system for transmission technique under considerations. The system capacity as well as the spectral losses, and the dispersion effects are parametrically investigated over wide range ranges of the set of affecting parameters {wavelength, ocean depth (and consequently the ocean pressure and temperature), and the chemical structure}. © 2012 Insan Akademika All Rights Reserved
