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Wireless Channel State-Aware and adaptive Epidemic Dissemination in Ad Hoc Networks

INTERNATIONAL JOURNAL OF WIRELESS INFORMATION NETWORKS 2014年第1期21卷 58-67页

作者： Kontos, Theofanis Anagnostopoulos, Christos Hadjiefthymiades, Stathes Univ Athens Pervas Comp Athens Greece Ionian Univ Dept Informat Corfu Greece Univ Glasgow Sch Comp Sci Glasgow Lanark Scotland Univ Aegean Dept Informat & Commun Syst Engn Mitilini Greece

Ad hoc networks are characterized by limited resources (e.g. energy, bandwidth). Efficient information dissemination while avoiding excessive energy cost can be achieved through the suitable design of a network. To this end we propose an information dissemination scheme which couples epidemic dissemination with adaptive modulation and coding (AMC). The proposed scheme tunes the message forwarding probability and the coding and modulation mode in order to achieve a balance between maximum coverage over the network and minimum energy expenditure. We achieve this based on the evaluation of suitably defined indicators related to the lower network layers and exploiting information on the current status of the wireless medium. Building on established previous AMC-related work, our simulation results indicate that our scheme brings significant improvement over non-adaptive approaches, comparable with other adaptive epidemic dissemination schemes. Our findings are quite promising for adaptive epidemic-based information dissemination schemes with a strong cross-layer component.

关键词： Epidemic information dissemination adaptive probabilistic information dissemination Ad hoc networks adaptive modulation and coding

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Throughput of HARQ Protocols on a Block Fading Channel

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IEEE COMMUNICATIONS LETTERS 2010年第3期14卷 257-259页

作者： Lagrange, Xavier Univ Europeenne Bretagne Inst Telecom Telecom Bretagne Bretagne France

This letter considers hybrid automatic repeat request (HARQ) protocols on a block Rayleigh fading channel. We derive the packet loss probability and the throughput for HARQ in closed-form. We propose a simple approximated but very accurate formula for the throughput. We deduce a cross-layer design of adaptive modulation and coding with HARQ.

关键词： Hybrid automatic repeat request adaptive modulation and coding cross-layer design wireless networks fading channels

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On joint order statistics in correlated Nakagami fading channels

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IEEE COMMUNICATIONS LETTERS 2007年第9期11卷 717-719页

作者： Kwan, Raymond Ho, Paul Leung, Cyril Simon Fraser Univ Sch Engn Sci Burnaby BC V5A 1S6 Canada Univ British Columbia Dept Elect & Comp Engn Vancouver BC V6T 1Z4 Canada

In this letter, the joint probability density function (pdf) of the order statistics for a set of correlated Nakagami-m fading channels is derived. This result is useful in analyzing the performance of a variety of diversity schemes which involve branch selection. The derivation also yields a computationally efficient method for obtaining the marginal pdf of the p-th order statistic for a set of correlated Nakagami-m fading channels.

关键词： adaptive modulation and coding multicode imperfect channel estimation CDMA Nakagami fading

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Link Adaptation Mechanisms Based on Logistic Regression Modeling

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IEEE COMMUNICATIONS LETTERS 2019年第5期23卷 942-945页

作者： Blanquez-Casado, Francisco Aguayo Tones, Maria del Carmen Gomez, Gerardo Keysight Technol SLU Malaga 29590 Spain Univ Malaga Dept Commun Engn Malaga 29002 Spain

In this letter, we obtain the optimal signal-to-noise ratio regions for the adaptive modulation and coding (AMC) over a set of correlated subcarriers. We use logistic regression to model the block error rate (BLER) with the aim of maximizing the throughput while keeping the BLER below a predefined target. We also study the robustness of a suboptimal optimization procedure, which maintains the relative distance among thresholds to that preserving the instantaneous BLER under the target. Moreover, we bring a new understanding of the outer loop link adaptation (OLLA) mechanism in terms of the AMC. We show that OLLA is able to converge (in average) to the thresholds designed by this suboptimal procedure. We also study the unstable behavior of OLLA implementations that update one offset per modulation and coding scheme, bringing out the need for new more flexible link adaptation mechanisms.

关键词： adaptive modulation and coding outer loop link adaptation logistic regression

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Markov model for admission control in the wireless AMC networks

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IEICE TRANSACTIONS ON COMMUNICATIONS 2006年第8期E89B卷 2230-2233页

作者： Kwon, Eunhyun Yeon, Hun-je Lee, Jaiyong Jung, Kyunghun Yonsei Univ Sch Elect & Elect Engn Seoul 120749 South Korea

In wireless adaptive modulation and coding (AMC) systems, modulation type of a user's connection can change and the ongoing connection might fail due to the change of modulation. In this paper, we approach the AMC-induced call admission control (CAC) problem by focusing on the guaranteed connection. Three classes of calls, new, handoff, and modulation-changed, are considered. We modify the guard-channel CAC scheme such that the modulation-changed calls, in addition to the handoff calls, are allowed to use the guard channel. Then we analyze a Markov model for the CAC scheme designed with long-term AMC in mind. The proposed approach will be an essential tool to determine the guard-channel thresholds in the wireless AMC networks.

关键词： call admission control adaptive modulation and coding wireless network

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Reinforcement Learning Based Efficient Underwater Image Communication

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IEEE COMMUNICATIONS LETTERS 2021年第3期25卷 883-886页

作者： Su, Wei Tao, Jincheng Pei, Yuehua You, Xudong Xiao, Liang Cheng, En Xiamen Univ Underwater Acoust Commun & Marine Informat Techno Xiamen 361005 Peoples R China Xiamen Univ Dept Informat & Commun Engn Xiamen 361005 Peoples R China

In this letter, we proposed an efficient underwater acoustic (UWA) image communication algorithm based on reinforcement learning which can improve the image quality while reduce the energy consumption and time delay in fast time variant UWA channels. In the proposed algorithm, the received image quality and other communication performance parameters are estimated at the sink continuously and then feedback to the sensor by an independent channel in order to avoid bandwidth loss caused by large time delay. At the sensor, the most suitable modulation and coding method is chosen to maximize a special designed value function in order to achieve the best efficient underwater image communication. Sea test results show that the proposed UWA image communication algorithm can reduce the bit-error rate by 3.1 dB, the energy consumption of the sensor by 26.9% and the time delay by 58.2%. The proposed algorithm can also shorten the convergence time by 47.4% compared with the model-free reinforcement learning underwater communication algorithm.

关键词： Image communication Image coding modulation Image quality Watermarking Delay effects Prediction algorithms Reinforcement learning adaptive modulation and coding underwater image communication

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Performance of a CDMA system employing AMC and multicodes in the presence of channel estimation errors

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IEEE TRANSACTIONS ON COMMUNICATIONS 2008年第2期56卷 189-193页

作者： Kwan, Raymond Leung, Cyril Univ British Columbia Dept Elect & Comp Engn Vancouver BC V6T 1Z4 Canada

The impact of channel state estimation errors in a CDMA system employing adaptive modulation and coding in conjunction with multicodes is studied. The channel is modelled as a finite-state Markov chain and the performances using (1) a simple moving average (SMA) filter (2) a hidden Markov model (HMM) filter to estimate the channel state are compared. The results show that the HMM filter is more robust and provides a significant throughput improvement over the SMA filter, especially when the channel estimate is quite noisy or the normalized Doppler rate is small.

关键词： CDMA adaptive modulation and coding multicode imperfect channel estimation Rayleigh fading hidden Markov model

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adaptive Packet Length and MCS Using Average or Instantaneous SNR

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2018年第11期67卷 10519-10527页

作者： Alnwaimi, Ghassan Boujemaa, Hatem King Abdulaziz Univ Jeddah 21589 Saudi Arabia Univ Carthage COSIM Lab SupCom El Ghazala 2083 Tunisia

In this paper, we propose a new adaptive link layer protocol that consists in adapting packet length and modulation and coding Scheme (MCS) to Average Signal to Noise Ratio or instantaneous SNR (ISNR). adaptive MCS and adaptive packet length offer higher throughput than adaptive MCS and fixed packet length as considered in previous studies. The best strategy is to adapt the MCS and packet length to ISNR. adaptive MCS and adaptive packet length offer 1-2 dB gains with respect to adaptive MCS and fixed packet length. The proposed adaptive link layer protocol has been implemented by quantizing the SNR on the feedback channel over four hits and yielding close results to unquantized SNR.

关键词： adaptive modulation and coding optimal packet length instantaneous SNR (ISNR) average SNR (ASNR)

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Joint Optimization of User-Experience and Energy-Efficiency in Wireless Multimedia Broadcast

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IEEE TRANSACTIONS ON MOBILE COMPUTING 2014年第7期13卷 1522-1535页

作者： Singhal, Chetna De, Swades Trestian, Ramona Muntean, Gabriel-Miro Indian Inst Technol IIT Delhi Bharti Sch Telecommun New Delhi 110016 India IIT Delhi Dept Elect Engn New Delhi 110016 India Middlesex Univ Comp Commun Dept London NW4 4BT England Dublin City Univ Sch Elect Engn Performance Engn Lab Dublin 9 Ireland

This paper presents a novel cross-layer optimization framework to improve the quality of user experience (QoE) and energy efficiency of the heterogeneous wireless multimedia broadcast receivers. This joint optimization is achieved by grouping the users based on their device capabilities and estimated channel conditions experienced by them and broadcasting adaptive content to these groups. The adaptive multimedia content is obtained by using scalable video coding (SVC) with optimal source encoding parameters resulted from an innovative cooperative game. Energy saving at user terminals results from using a layer-aware time slicing approach in the transmission stage. A trade-off between energy saving and QoE is observed, and is incorporated in the definition of a utility function of the players in the formulated heterogeneous user composition and physical channel aware game. An adaptive modulation and coding scheme is also optimally incorporated in order to maximize the reception quality of the broadcast receivers, while maximizing the network broadcast capacity. Compared to the conventional broadcast schemes, the proposed framework shows an appreciable improvement in QoE levels for all users, while achieving higher energy-savings for the energy constrained users.

关键词： adaptive multimedia broadcast and multicast scalable video coding adaptive modulation and coding heterogeneous users energy saving quality of user experience

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Optimizing Joint Erasure- and Error-Correction coding for Wireless Packet Transmissions

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2008年第11期7卷 4586-4595页

作者： Berger, Christian R. Zhou, Shengli Wen, Yonggang Willett, Peter Pattipati, Krishna Univ Connecticut Dept Elect & Comp Engn Storrs CT 06269 USA MIT Informat & Decis Syst Lab Cambridge MA 02139 USA

To achieve reliable packet transmission over a wireless link without feedback, we propose a layered coding approach that uses error-correction coding within each packet and erasure-correction coding across the packets. This layered approach is also applicable to an end-to-end data transport over a network where a wireless link is the performance bottleneck. We investigate how to optimally combine the strengths of error- and erasure-correction coding to optimize the system performance with a given resource constraint, or to maximize the resource utilization efficiency subject to a prescribed performance. Our results determine the optimum tradeoff in splitting redundancy between error-correction coding and erasure-correction codes, which depends on the fading statistics and the average signal to noise ratio (SNR) of the wireless channel. For severe fading channels, such as Rayleigh fading channels, the tradeoff leans towards more redundancy on erasure-correction coding across packets, and less so on error-correction coding within each packet. For channels with better fading conditions, more redundancy can be spent on error-correction coding. The analysis has been extended to a limiting case with a large number of packets, and a scenario where only discrete rates are available via a finite number of transmission modes.

关键词： Reliable transmission fountain codes layered coding adaptive modulation and coding inter- and intra-packet coding

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