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64th IEEE Vehicular Technology Conference

作者： Alvarado, Alex Carrasco, Hector Feick, Rodolfo Univ Tecn Federico Santa Maria Dept Elect Engn Valparaiso 1680 Chile

ISBN: (纸本)9781424400621

In this paper we present a novel performance analysis of bit-interleaved coded modulation (BICM) over AWGN channel for different modulation schemes considering a finite block length and suboptimal metrics calculation. Using the known BICM capacity analysis as well as the Gallager bound, we show that among many known modulations, only three M-ary quadrature amplitude modulation (QAM) are necessary to ensure the maximization of the channel capacity. We analyze the maximum throughput and the switching thresholds of the system, and we compare the theoretical analysis with simulation results of practical strong codes, i.e., turbo codes. We show that if the modulation and code are well adapted, the optimal throughput decreases by less than 1% when suboptimal metrics are used. We show also, that the turbo codes throughput is within 1.5 dB of the new bound, and the SNR switching thresholds, are shifted by 1.5 dB with respect to the theoretical analysis.

关键词： adaptive modulation and coding Coded modulation Bit-Interleaved Coded modulation Channel Capacity Gallager bound Turbo Codes SNR Thresholds

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Cross Layer Strategies in Wireless Networks

Cross Layer Strategies in Wireless Networks

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3rd International Conference on Signals, Circuits and Systems

作者： Bahloul, Ramzi Boujemaa, Hatem Siala, Mohamed Higher Sch Commun Tunis TECHTRA Res Unit Tunis Tunisia

ISBN: (纸本)9781424443970

In this paper, we evaluate the throughput performance of Hybrid Automatic Repeat reQuest (HARQ) protocols using adaptive modulation and coding (AMC) based on either the instantaneous Signal to Noise Ratio (SNR) or the average SNR. We also propose a cross layer optimization algorithm in order to offer the highest throughput at the physical (PHY) layer and verify some Quality Of Service (QOS) constraints at the Medium Access (MAC) layer such as the Probability of Packet Erasure (PPE) and the transmission delay. Simulation results are also provided in different contexts in order to verify the tightness of the derived results.

关键词： HARQ protocols adaptive modulation and coding Cross-Layer Design Rayleigh fading channels

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Optimization of Energy Efficiency in the Downlink LTE Transmission

Optimization of Energy Efficiency in the Downlink LTE Transm...

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IEEE International Conference on Communications (ICC) / Wireless Communications Symposium / 3rd Workshop on Optical Wireless Communications (OWC)

作者： Bossy, Bartosz Kryszkiewicz, Pawel Bogucka, Hanna Poznan Univ Tech Fac Elect & Telecommun Chair Radio Commun Poznan Poland

ISBN: (纸本)9781467389990

In this paper, we investigate the energy-efficient resource allocation problem in the downlink of an Orthogonal Frequency Division Multiple Access (OFDMA) system with multiple users. A iterative algorithm is developed to maximize the overall energy efficiency of the downlink transmission by allocating the resource blocks (RBs) and the transmit power, which is constant for all RBs assigned to a given user. Moreover, we assume that all RBs assigned to the same user must use the same modulation and coding scheme (MCS), as in the LTE specification. In this form our optimization problem belongs to a broad class of problems called Mixed-Integer Nonlinear Fractional Problem (MINLFP), which is very difficult to solve analytically in the original form. Hence, in order to solve it, we propose the iterative algorithm with fast convergence based on the Dinkelbach method. In each iteration, the solution for the power and resource blocks allocation is derived by the numerical method using the Karush-Kuhn-Tucker (KKT) multipliers and KKT conditions, while modulation and coding scheme, for each user, is obtained by the iterative algorithm. Simulation results show that despite the computational simplicity of the proposed solution, it achieves better results than the solutions known from the literature.

关键词： Energy efficiency adaptive modulation and coding OFDM green communication LTE

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Improvement of QoS in VANET with Different Mobility Patterns

Improvement of QoS in VANET with Different Mobility Patterns

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International Conference on Radar, Communication and Computing (ICRCC)

作者： Dorge, Prabhakar D. Dorle, Sanjay S. Chakole, Megha B. Thote, Dhiraj K. YCCE Dept Elect & Tel Nagpur Maharashtra India GHRCE Dept Elect Nagpur Maharashtra India

ISBN: (纸本)9781467327589;9781467327565

In the past, many researchers depend highly on various real life environmental short coverage area networks to analyze the performance of various routing algorithms. Recent ever-increasing interest in vehicular ad hoc network communication (VAC) necessitates vehicular movement performance study via different mobility pattern simulation. Unlike many other works, we present a study on the performance of various routing algorithms with different mobility patterns for large coverage area networks like WiMAX using NS2. Also we are going to improve various quality of service (QoS) parameters like throughput, jitter, delay, packet delivery ratio and packet loss ratio for different scenario networks by using various routing algorithms with different mobility patterns, multiple input multiple output (MIMO) and adaptive modulation and coding (AMC) technique.

关键词： VANET WiMAX QoS routing protocols MIMO adaptive modulation and coding

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Advanced Wireless Communications and Internet 3

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2011年

作者： Glisic Savo G.

ISBN: (数字)9781119991625

ISBN: (纸本)9780470711224

The new edition of Advanced Wireless Communications: 4G Cognitive and Cooperative Broadband Technology, 2nd Edition, including the latest developments In the evolution of wireless communications, the dominant challenges are in the areas of networking and their integration with the Future Internet. Even the classical concept of cellular networks is changing and new technologies are evolving to replace it. To reflect these new trends,Advanced Wireless Communications & INTERNET builds upon the previous volumes, enhancing the existing chapters, and including a number of new topics. Systematically guiding readers from the fundamentals through to advanced areas, each chapter begins with an introductory explanation of the basic problems and solutions followed with an analytical treatment in greater detail. The most important aspects of new emerging technologies in wireless communications are comprehensively covered including: next generation Internet; cloud computing and network virtualization; economics of utility computing and wireless grids and clouds. This gives readers an essential understanding of the overall environment in which future wireless networks will be operating. Furthermore, a number of methodologies for maintaining the network connectivity, by using tools ranging from genetic algorithms to stochastic geometry and random graphs theory, and a discussion on percolation and connectivity, are also offered. The book includes a chapter on network formation games, covering the general models, knowledge based network formation games, and coalition games in wireless ad hoc networks. Illustrates points throughout using real-life case studies drawn from the author's extensive international experience in the field of telecommunications Fully updated to include the latest developments, key topics covered include: Advanced routing and network coding; Network stability control; Relay-assisted Wireless Networks; Multicommodity flow optimization problems, flow optimizatio

关键词： Advanced Wireless Communications and Internet automatic decision threshold level control ADTLC frequency hopping modulation wireless ad hoc networks biologically inspired paradigms advanced routing and network coding game theory adaptive modulation and coding multiuser communication Orthogonal Frequency Division Multiplexing OFDM multicarrier CDMA ultrawide band radio

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Performance Analysis of Cross Layer Adaptation of modulation and coding in Slow, Flat Fading Channels

Performance Analysis of Cross Layer Adaptation of Modulation...

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16th IST Mobile and Wireless Communications, vol.3

作者： Z. Katona J. Bito German Aerospace Center (DLR) Institute of Communications and Navigation Oberpfaffenhofen Germany Budapest University슠of슠Technology슠and슠Economics Budapest Hungary

The end-to-end Quality of Service (QoS) is getting more and more importance nowadays. QoS is composed of many parameters, like bit error rate (BER) delay, jitter etc. This paper will make the mathematical analysis of the spectral efficiency of adaptive modulation and coding (AMC) which - unlike conventional adaptive modulation and coding - takes into consideration the bit error requirements of different service classes, beside the instantaneous channel conditions. The paper will provide results on average spectral efficiency, mode selection probabilities and average bit error rate performance of proposed and conventional adaptive modulation (AM) in multiplicative, slow Rayleigh fading channel. The fading is assumed to be slow enough, that the adaptive modulation can adapt to the variable channel state.

关键词： adaptive modulation and coding Quality of Service Rayleigh fading Spectral Efficiency

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Channel-aware MAC performance of AMC-ARQ-based wireless systems

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EURASIP JOURNAL ON WIRELESS COMMUNICATIONS AND NETWORKING 2013年第1期2013卷 1页

作者： Carrasco, Loren Femenias, Guillem Ramis, Jaume Univ Balear Isl UIB Mobile Commun Grp Palma De Mallorca 07122 Spain

This paper proposes a novel framework for the cross-layer design and optimization of wireless networks combining adaptive modulation and coding (AMC) at the physical (PHY) layer with automatic repeat request and channel-aware multiuser scheduling protocols at the data link control (DLC) layer. The proposed framework is based on the use of first-order two-dimensional discrete time Markov chains (DTMCs) jointly modeling the AMC scheme and the amplitude and rate of change of the wireless channel fading envelope. The behavior of the scheduler is embedded into the multidimensional PHY layer Markov model through the use of a service-vacation process. Using this PHY-media access control (MAC) Markov model, the quality of service performance at the DLC layer is discussed considering two different approaches. The first one relies on an analytical framework that is based on the multidimensional DTMC jointly describing the statistical behavior of the arrival process, the queuing system, and the PHY layer. The second one is rooted in the use of the effective bandwidth theory to model the packet arrival process and the effective capacity theory to model the PHY/MAC behavior. Both the DTMC-based and effective bandwidth/capacity-based approaches are analyzed and compared in a cross-layer design aiming at maximizing the average throughput of the system where constraints on the maximum tolerable average packet loss and delay are to be fulfilled.

关键词： adaptive modulation and coding Automatic repeat request Channel-aware scheduling Markov models Effective capacity Cross-layer design

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Recognition of error correcting codes based on CNN with block mechanism and embedding

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DIGITAL SIGNAL PROCESSING 2021年 111卷 102986-102986页

作者： Li, Sida Zhou, Jing Huang, Zhiping Hu, Xiaochang Natl Univ Def Technol Coll Intelligent Sci Changsha 410073 Peoples R China

An error correcting code type recognition technique based on a deep learning approach is proposed in this paper. This problem could be addressed in the context of non-cooperative communications or adaptive coding and modulation. Inspired by text classification, we proposed a convolutional neural network (CNN) model improved by embedding and block mechanism to classify the linear block code, convolutional code, and turbo code with the only knowledge of the noisy information streams. It achieves higher recognition performance than the algorithms which are based on traditional deep learning and rank calculation. Further results show that the performance is greatly affected by block length and the dimension of the embedding layer. In a nutshell, the CNN with block mechanism and embedding is a promising feature extraction and classification technique, and it is suitable for the recognition of different kinds of communication signals. (C) 2021 Elsevier Inc. All rights reserved.

关键词： adaptive modulation and coding Blind/semi-blind estimation Deep learning Text classification Forward error correcting (FEC) code

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Blind parameter estimation of turbo convolutional codes: Noisy and non-synchronized scenario

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DIGITAL SIGNAL PROCESSING 2019年 95卷 102577-000页

作者： Swaminathan, R. Madhukumar, A. S. Indian Inst Technol Indore Discipline Elect Engn Indore 453552 Madhya Pradesh India Nanyang Technol Univ Sch Comp Sci & Engn Singapore 639798 Singapore

Blind estimation of forward error correction code parameters at the receiver plays a significant role in non-cooperative communication, adaptive modulation and coding systems, and reconfigurable receiver systems. Turbo convolutional codes, a parallel concatenation of multiple convolutional codes, are used in digital communication and storage systems to achieve low bit error rate. The present paper proposes innovative algorithms for the blind estimation of code parameters and reconstruction of turbo convolutional encoder over noisy scenario. The turbo convolutional code is designed using two component codes along with an interleaver. Recursive systematic convolutional codes are used as component codes. Any imperfection in synchronization of received data for the proposed code parameter estimation algorithm is compensated through a bit position adjustment parameter. The performance of the proposed algorithms in terms of parameter estimation accuracy is investigated for different modulation order, code rate, and constraint length values. It is observed that the performance improves with decrease in modulation order and constraint length values. (C) 2019 Elsevier Inc. All rights reserved.

关键词： adaptive modulation and coding Blind estimation Non-cooperative systems Reconfigurable receiver systems Recursive systematic convolutional codes And turbo convolutional codes

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A 10-state model for an AMC scheme with repetition coding in mobile wireless networks

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EURASIP JOURNAL ON WIRELESS COMMUNICATIONS AND NETWORKING 2013年第1期2013卷 1页

作者： Nguyen Quoc-Tuan Dinh-Thong Nguyen Lam Sinh Cong Vietnam Natl Univ Hanoi Vietnam Univ Technol Sydney Sydney NSW 2007 Australia

In modern broadband wireless access systems such as mobile worldwide interoperability for microwave access (WiMAX) and others, repetition coding is recommended for the lowest modulation level, in addition to the mandatory concatenated Reed-Solomon and convolutional code data coding, to protect vital control information from deep fades. This paper considers repetition coding as a time-diversity technique using maximum ratio combining (MRC) and proposes techniques to define and to calculate the repetition coding gain G (r) and its effect on bit error rate (BER) under the two fading conditions: correlated lognormal shadowing and composite Rayleigh-lognormal fading also known as Suzuki fading. A variable-rate, variable-power 10-state finite-state Markov channel (FSMC) model is proposed for the implementation of the adaptive modulation and coding (AMC) scheme in mobile WiMAX to maximize its spectral efficiency under constant power constraints in the two fading mechanisms. Apart from the proposed FSMC model, the paper also presents two other significant contributions: one is an innovative technique for accurate matching of moment generating functions, necessary for the estimation of the probability density function of the combiner's output signal-to-noise ratio, and the other is efficient and fast expressions using Gauss-Hermite quadrature approximation for the calculation of BER of QPSK signal using MRC diversity reception.

关键词： Lognormal fading Suzuki fading Gauss-Hermite polynomial Moment generating function WiMAX adaptive modulation and coding Repetition coding Finite-state Markov channel model

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