Results 241 to 250 of about 75,987 (284)

Constellation design with geometric and probabilistic shaping

Optics Communications, 2018
Abstract A systematic study, including theory, simulation and experiments, is carried out to review the generalized pairwise optimization algorithm for designing optimized constellation. In order to verify its effectiveness, the algorithm is applied in three testing cases: 2-dimensional 8 quadrature amplitude modulation (QAM), 4-dimensional set ...
Shaoliang Zhang, Fatih Yaman
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Geometric Constellation Shaping Using Initialized Autoencoders

2021 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom), 2021
Geometric constellation shaping is a promising technique to boost the transmission capacity of communication systems. Earlier, traditional optimization methods in constellation design lead to several advanced quadrature amplitude modulation (QAM) formats, such as star QAM, cross QAM, and hexagonal QAM.
Amir Omidi, Ming Zeng, Jiachuan Lin, Leslie A. Rusch   +3 more
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A Constellation-shaped 127QAM scheme based on Geometric Shaping

Asia Communications and Photonics Conference 2021, 2021
A novel constellation-shaped 127QAM scheme based on geometric-shaping is proposed. In a 140-Gb/s simulation system, the proposed scheme has a 0.87dB OSNR gain and a 186km transmission-distance gain at 2e-2 BER, compared with uniform-128QAM.
Xiangyu Liu, Qi Zhang, Ran Gao, Xiangjun Xin, Xishuo Wang, Huan Chang, Bingchun Liu, Wenmao Zhou, Feng Tian, Qinghua Tian, Zhipei Li   +10 more
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PAR reduction via constellation shaping

2000 IEEE International Symposium on Information Theory (Cat. No.00CH37060), 2002
We introduce a novel scheme using a constellation shaping approach to reduce the peak-to-average ratio (PAR) in orthogonal frequency-division multiplexing (OFDM) systems. In the time domain, the peak power bound traces out a hypercube boundary. We map this square time-domain boundary back to the frequency domain via the DFT and construct a method for ...
H. Kwok, D. Jones
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Constellation Shaping using LDPC Codes

2007 IEEE International Symposium on Information Theory, 2007
It is well-known that a Gaussian source distribution is required for maximum information transfer across a Gaussian channel. In a coded modulation system an equiprobable symbol constellation loses at most 1.53 dB when compared to a Gaussian source. To bridge this shaping gap, a code can be used to make the source distribution more Gaussian over an ...
Sunil Kaimalettu, Andrew Thangaraj, Matthieu Bloch, Steven W. McLaughlin   +3 more
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Constellation shaping in optical transport network

AOPC 2020: Optical Information and Network, 2020
In the optical transport network, the high-dimension equiprobable constellation is used to increase the information transmission rate and the forward error correction code is used to improve the system performance. However, adopting the equiprobable constellation will lead to some information loss according to the Shannon theory and the performance of ...
Dekun Zhou, Lei Li, Qiang Rao, Tao He, Zheng Zhou, Jun Sun, Pu Chen, Peng Zhan, Lu Ye, Yi Tang, Yi He, Junxi Wang, Hanlin Jiao, Jinhua Zhan, Jingru Li, Shuo Yang, Jing Dai   +16 more
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Polar Coding for Multilevel Shaped Constellations

Advanced Photonics 2018 (BGPP, IPR, NP, NOMA, Sensors, Networks, SPPCom, SOF), 2018
We present recent advancements of polar coding suitable for next-generation optical communications, which call for high-throughput operation under low-power and low-latency constraints. We particularly discuss polar coding design for high-order modulation with constellation shaping.
Toshiaki Koike-Akino, Ye Wang, David S. Millar, Keisuke Kojima, Kieran Parsons   +4 more
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On optimal shaping of multidimensional constellations

IEEE Transactions on Information Theory, 1994
Summary: A scheme for the optimal shaping of multidimensional constellations is proposed. This scheme is motivated by a type of structured vector quantizer for memoryless sources, and results in \(N\)-sphere shaping of \(N\)-dimensional cubic lattice-based constellations. Because \(N\)-sphere shaping is optimal in \(N\) dimensions, shaping gains higher
Laroia, Rajiv, Farvardin, Nariman, Tretter, Steven A.   +2 more
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Probabilistic Constellation Shaping: An Implementation Perspective

Optical Fiber Communication Conference (OFC) 2022, 2022
This tutorial reviews recent advances in probabilistic constellation shaping (PCS) with particular focus on implementation perspectives. We analyze the complexity of several known shaping methods and discuss performance and complexity tradeoffs in different application scenarios.
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Visionary Practices Shaping Power Constellations

2019
The assessment of the impacts of sociotechnical futures on processes of innovation is a continuing challenge for technology assessment (TA). Imaginations of the future shape communications and actions in the present. They do not deliver any information about the outcome of these processes.
Lösch, Andreas, Schneider, Christoph, Heil, Reinhard   +2 more
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