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10th International Conference on Wireless Communications and Signal Processing (WCSP)

作者： Liu, Mengmeng Li, Shuangyang Li, Qian Bai, Baoming Xidian Univ State Key Lab ISN Xian Shaanxi Peoples R China Sci & Technol Commun Networks Lab Shijiazhuang Hebei Peoples R China

ISBN: (纸本)9781538661192

In this paper, an adaptive modulation and coding (AMC) scheme based on faster-than-Nyquist (FTN) signaling is considered, where FTN signaling is implemented with multi-layer superposition coded modulation (SCM). Compared to the traditional AMC schemes, the proposed AMC scheme adjusts the number of layers K and the FTN compression factor r rather than the code rates and modulation orders. Simulation results show that the proposed AMC scheme is able to achieve a wide range of spectral efficiency. Furthermore, the achievable spectral efficiency approaches the ultimate capacity of the shaping pulse, and its performance can outperform the constrained capacity of orthogonal signaling with the same spectral efficiency.

关键词： adaptive modulation and coding faster-than-Nyquist signaling superposition coded modulation

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Multiuser Resource Allocation with adaptive modulation and LDPC coding for Heterogeneous Traffic in OFDMA Downlink

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IEEE TRANSACTIONS ON COMMUNICATIONS 2012年第10期60卷 2915-2925页

作者： Mazzotti, Matteo Moretti, Simone Chiani, Marco Univ Bologna CIRI ICT CNIT I-40126 Bologna Italy Univ Bologna CNIT I-40126 Bologna Italy

We describe an optimization technique for multiuser resource allocation assuming adaptive modulation and coding (AMC) in OFDMA radio downlink communications. The resource allocation process is based on the dual solution of a weighted sum-rate maximization problem. In particular, to realistically address IP-based video and data communications, the set of considered constraints include the number of bits actually present in the different transmission buffers. Furthermore, we propose an innovative AMC solution, based on M-QAM modulation and LDPC codes, jointly working with the scheduler and capable to maximize the throughput while guaranteeing a given set of performance requirements. A simple weight adaptation algorithm is introduced to properly tune the trade off between opportunistic transmissions and fairness among users. Several simulation results are presented to validate the proposed approach and a comparison with more traditional schemes is provided. In particular, we show that a good trade off between user fairness and opportunistic exploitation of the radio channel can be reached with the proposed strategies, improving the communication quality for both real-time video and non real-time data applications.

关键词： adaptive modulation and coding LDPC OFDMA resource allocation multiuser scheduling

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Modeling and analysis of applying adaptive modulation coding in wireless multicast and broadcast systems

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WIRELESS NETWORKS 2011年第5期17卷 1373-1386页

作者： Liang, Yu-Cheng Chou, Ching-Chun Wei, Hung-Yu Natl Taiwan Univ Dept Elect Engn Taipei 10764 Taiwan

Traditional wireless communications only utilize fixed-rate multicast and broadcast. In other words, only the most robust modulation and coding scheme can be applied for data transmission. Such a scheme fails to sufficiently exploit the potential gains of multicast and broadcast, resulting in bandwidth waste. To overcome such a problem, investigating the rate adaptation of multicast and broadcast wireless systems is the primary task. Unlike the traditional wireless systems, this paper presents an analytical model with rate adaptation for both multicast and broadcast. adaptive modulation and coding are applied to achieve rate adaptation. We construct a stochastic model by using Finite State Markov chains for the multicast broadcast system modeling. The model's outputs are shown to approximate to the results of our system level simulations. The model derives the performance of rate adaptation in multicast and broadcast. With the deduced modeling results, we can predict the system throughput providing the channel states, and the modulation and coding schemes variations.

关键词： adaptive modulation and coding Markov chain model Multicast Broadcast

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A new fuzzy based scheme to optimize buffer constrained throughput of a wireless link using adaptive modulation, coding and transmit power

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JOURNAL OF INTELLIGENT & FUZZY SYSTEMS 2017年第3期32卷 2499-2507页

作者： Taki, Mehrdad Univ Qom Qom Iran

This paper presented a new fuzzy based optimization framework for wireless link adaptation which maximizes throughput subject to Buffer length, Bit Error Rate (BER) and average power constraints. Buffer constrained throughput of a link is called effective capacity. At first, we present two schemes to optimize the effective capacity of a wireless link, in an analytical approach, with constant or adaptive power transmission. As shown, the scheme with constant power transmission works without any need to probability density function (PDF) of channel's SNR. However, a considerable performance improvement is seen by using adaptive power transmission at the cost of more complicated design. In analytical approach, provisioning average power constraint requires knowledge on PDF of the link's SNR which may not be available in practical systems especially mobile networks. We design a new fuzzy based scheme for adaptive power transmission without any need to PDF which provide instantaneous BER, buffer and average power constraints. Our numerical evaluations for adaptive LDPC or convolutional coded, QAM modulated transmission, show that after a reasonable period of time the throughput of our proposed scheme converges to its optimum value by analytical approach.

关键词： Link adaptation adaptive modulation and coding buffer constraint cross layer design

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Throughput Performance Models for adaptive modulation and coding under Fading Channels

Throughput Performance Models for Adaptive Modulation and Co...

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IEEE Wireless Communications and Networking Conference

作者： Miguel Lopez-Benitez Dept. Electrical Engineering and Electronics University of Liverpool

ISBN: (纸本)9781467398152

Modern wireless communication systems adapt the employed modulation and coding Scheme (MCS) to the instantaneous channel quality in order to maximise the amount of bits correctly transmitted per time unit (i.e., the throughput). An important aspect in the study of this technique, referred to as adaptive modulation and coding (AMC), is the characterisation of the link throughput performance under realistic fading channels. In this context, this work derives analytically tractable closed-form expressions for the link throughput performance of AMC under Rayleigh, Nakagami-m, Nakagami-q (Hoyt), Nakagami-n (Rice), η-μ and κ-μ fading channels. The correctness and accuracy of the obtained expressions is corroborated numerically and with results from an LTE link level AMC simulator.

关键词： adaptive modulation and coding Link adaptation Throughput performance Fading channels LTE

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Spectrum Efficiency of Jointing adaptive modulation coding and Truncated ARQ With QoS Constraints

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IEEE ACCESS 2018年 6卷 46915-46925页

作者： Jiao, Wanguo Ding, Haofan Wu, Haiqing Yu, Gang Nanjing Forestry Univ Coll Informat Sci & Technol Nanjing 210037 Jiangsu Peoples R China

Spectrum efficiency (SE) and QoS guarantee are two critical issues in wireless communication systems. The truncated ARQ and the adaptive modulation and coding (AMC) are often used to improve the SE and transmission reliability in wireless communications. In this paper, we study the SE and QoS performance of a system with a cross-layer combining of the truncated ARQ with the AMC. First, we analyze the performance of current combinations of the ARQ and the AMC. The analysis results indicate that the current combination is too "ineffectiveness'' or "conservative.'' Then, based on the analysis, we design a new rule for the AMC, which is used to adaptively choose transmission mode. Through analyzing the AMC and the combination algorithm using the proposed rule, both the SE and the packet dropped probability of the system are improved. Furthermore, the analysis result also point outs the suitable scenario of each algorithm. Simulation results verify the analysis result and demonstrate that the proposed algorithm can achieve higher SE while the QoS requirement is guaranteed. At last, to further improve the SE of the system, we propose an algorithm jointing power control and the combination of the ARQ with the AMC under the QoS constraint.

关键词： Spectrum efficiency adaptive modulation and coding ARQ QoS power control

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Performance Comparison of adaptive modulation and coding in OFDM Systems Using Signaling and Automatic modulation Classification

Performance Comparison of Adaptive Modulation and Coding in ...

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International OFDM Workshop

作者： L. Haering C. Kisters Chair of Communication Systems University Duisburg-Essen

ISBN: (纸本)9783800733606

This paper compares the system performance of signaling and automatic modulation classification in adaptive orthogonal frequency division multiplexing (OFDM)-based systems in time-division duplex (TDD) mode. In previous theoretical contributions, transmitter-side joint adaptive modulation and coding (AM+C) techniques have been proposed which can be used to either increase the data rate or, alternatively, improve the link reliability. Since the receiver must be synchronized to the transmit parameters, the required signaling overhead reduces the benefit of adaptive modulation and coding when applied to practical systems. Numerical results in terms of the effective data bandwidth efficiency reveal the potential of recently developed automatic modulation classifiers as an alternative to conventional signaling schemes.

关键词： OFDM adaptive modulation and coding Automatic modulation classification Signaling

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An adaptive modulation coding Cross-Layer Optimization Strategy with Packet Successful Transmission and Delay Constraints

An Adaptive Modulation Coding Cross-Layer Optimization Strat...

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Biennial Symposium on Communications (BSC)

作者： Tian, Taotao Fang, Xiaojie Liu, Lizhe Li, Zunqi Huang, Kaiwen Harbin Inst Technol Sch Elect & Informat Engn Harbin Peoples R China Sci & Technol Commun Networks Lab Shijiazhuang Peoples R China

ISBN: (纸本)9781665493802

Based on the analysis of the data link layer buffer queue state and the impact of application layer data flows on the physical layer of wireless communication nodes, this paper analyzes the restriction of communication link delay on the transmit power of nodes. Building on this analysis, a cross-layer optimization strategy is proposed with the goal of maximizing energy efficiency (EE), which selects the optimal adaptive modulation and coding (AMC) switching threshold and optimal power selection while considering the constraints of successful packet transmission rate and communication link delay. Finally, simulations are conducted to demonstrate the significant EE advantages of the proposed cross-layer optimization strategy.

关键词： adaptive modulation and coding Queuing Analysis Cross-Layer Design

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Cross-layer Design and Analysis for FSO Links Using Automatic Repeat Request and adaptive modulation/coding Schemes 9

Cross-layer Design and Analysis for FSO Links Using Automati...

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9th International Symposium on Communication Systems, Networks & Digital Signal Processing (CSNDSP)

作者： Mai, Vuong V. Thang, Truong C. Pham, Anh T. Univ Aizu Comp Commun Lab Aizu Wakamatsu Fukushima 9658580 Japan

ISBN: (纸本)9781479925810

This paper introduces a framework for cross-layer management of data transmissions in free-space optical (FSO) systems over atmospheric turbulence channels, in which link layer automatic repeat request (ARQ) and physical layer adaptive modulation and coding (AMC) are integrated to improve the system's spectral efficiency. The system performance is analytically studied in terms of average frame-error rate and average spectral efficiency, for which we derive closed-form expressions. In numerical results, we show how the proposed scheme outperforms a conventional one, and discuss cross-layer designs for parameters' selection in both physical and link layers to optimise the system performance over different atmospheric turbulence conditions.

关键词： FSO ARQ adaptive modulation and coding

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adaptive modulation and Code Channel Elimination for Vector coding System

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IEICE TRANSACTIONS ON COMMUNICATIONS 2009年第5期E92B卷 1538-1545页

作者： Takeda, Daisuke Nakagawa, Masao Keio Univ Dept Sci & Technol Yokohama Kanagawa 2230061 Japan

Vector coding (VC) is a kind of eigen mode transmission scheme which is typically considered in MIMO systems. In VC systems, several code channels corresponding to the eigenvalues of the channel matrix are created. However, any code channels with low eigenvalues will cause a degradation in performance. In this paper, adaptive modulation and coding (AMC) for a VC system is proposed. In addition to AMC, the number of code channels is adaptively changed by code channel elimination. We show that the BER performance of VC is better than that of MMSE. Secondly, we also show the throughput performance of the proposed scheme is improved compared with the maximum throughput of each individual MCS.

关键词： vector coding adaptive code channel elimination adaptive modulation and coding channel estimation

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