Results 211 to 220 of about 117,165 (263)

A group of modulation schemes for adaptive modulation

2008 11th IEEE Singapore International Conference on Communication Systems, 2008
Adaptive modulation increases the throughput of a wireless network by adjusting the modulation scheme to the channel status. To have more capacity and more flexibility in using adaptive modulation, our research attempts to find a group of modulation schemes, which includes M-QAM where the number of signal points is not a power of 2, as well as non ...
null Anh Tuan Le, null Kiyomichi Araki
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Modulation Schemes for Visible Light Communications

2019 International Conference on Advanced Communication Technologies and Networking (CommNet), 2019
Visible light communication (VLC) is one of the most recent technological breakthroughs in wireless communications and it is expected to contribute significantly on future generations of mobile communications. The fundamental feature of VLC is the use of visible light spectrum to transmit data along with the traditional use for illumination.
Amna Aliaberi, Paschalis C. Sofotasios, Sami Muhaidat   +2 more
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SMOOTH MORPHISMS OF MODULE SCHEMES

Proceedings of the London Mathematical Society, 2002
Let $\varphi:A\to B$ be a homomorphism of finite-dimensional algebras over an algebraically closed field and $\varphi^{(c)}:{\rm mod}_B^c\to{\rm mod}_A^c$ the induced morphism of the associated module schemes for any integer $c\geq 1$. We prove that if the induced functor ${\rm mod\,} B\to{\rm mod\,} A$ is hom-controlled then the restriction of ...
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Adaptive modulation schemes

2009 IEEE/LEOS Summer Topical Meeting, 2009
In this presentation we will discuss recent advances in adaptive modulation schemes for ultra high bit capacity optical networks. This paper focuses on optimising the sub-carrier spacing for such high capacity networks..
A.D. Ellis, I. Tomkos, A.K. Mishra, J. Zhao, S.K. Ibrahim, P. Frascella, F.C.G. Gunning   +6 more
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A Scheme of Fractional Modulation for Wireless OFDM

2006 Symposium on Communications and Vehicular Technology, 2006
This work proposes a new multi-carrier transmission scheme through the use of a fractionally modulation before data transmission. The idea is to exploit the correlation between the OFDM symbols at neighboring sub-carriers by means of an interpolation process.
BENEDETTO, FRANCESCO, GIUNTA, GAETANO
openaire   +3 more sources

An ARQ Scheme with Memory and Integrated Modulation

IEEE Transactions on Communications, 1987
In this paper, the integration of the modulation operation in an automatic-repeat-request scheme, using error-detecting codes, is analyzed. A new protocol is described, in which the modulation operation facilitates the recovery of the transmitted code word.
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A Novel Modulation Scheme of Polar Codes

2018 14th International Wireless Communications & Mobile Computing Conference (IWCMC), 2018
To improve the spectrum efficiency of high-order modulation polar codes, a novel modulation strategy, namely displacement of balanced modulation (DBM) is proposed in this paper. This algorithm can balance the performance between bit levels under the universal encoder and decoder by adding a shift mapping matrix.
Xiaotong Jia, Fang Wang, Yanzan Sun, Shunqing Zhang   +3 more
openaire   +1 more source

Retransmission diversity schemes for multicarrier modulations

IEEE Transactions on Wireless Communications, 2006
In this work, we present some simple techniques for enhancing the diversity provided by retransmissions in OFDM and DMT modulations. The primary techniques of interest are symbol interleaving and mapping diversity for retransmissions. Symbol interleaving involves retransmitting packet symbols through different subcarriers of the same channel, while ...
Harvind Samra, Zhi Ding 0001
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Recent results for chaotic modulation schemes

ISCAS 2001. The 2001 IEEE International Symposium on Circuits and Systems (Cat. No.01CH37196), 2002
By generalizing the waveform communications concept, this paper develops exact expressions, verified by computer simulations, for the noise performance of the coherent antipodal Chaos Shift Keying (CSK), coherent Differential Chaos Shift Keying (DCSK) and differentially coherent DCSK modulation schemes.
Géza Kolumbán, Michael Peter Kennedy
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A trellis-coded chaotic modulation scheme

2006 IEEE International Conference on Communications, 2006
Recently, a chaotic modulation has been proposed and attracts many researchers' attention because of some properties such as noise-like signal, nonlinearity, and pseudo-periodicity. The chaotic modulation is usually treated as a secure transmission scheme rather than an efficient scheme in terms of channel noise.
Eiji Okamoto, Yasunori Iwanami
openaire   +1 more source