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Delay constrained throughput optimised joint scheduling and link adaptation scheme based on imperfect channel state information

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IET COMMUNICATIONS 2015年第15期9卷 1812-1820页

作者： Taki, Mehrdad Univ Isfahan Esfahan Iran

This study presents novel joint scheduling and link adaptation schemes (JSL) to maximise a weighted sum of throughputs of wireless links, while their possibly different minimum required throughputs and packet error rate (PER), average power and delay constraints are provisioned. Weights are assigned based on the importance and requirements of the links. Notable features of the proposed scheme in comparison with the previously presented utility based scheduling schemes are: (a) in the designed scheme a statistical bound is presented for the delay instead of average delay constraint or long term queuing delay behaviour, (b) designed transmission scheme utilises adaptive modulation and coding provisioning PER constraint and may be integrated with H automatic repeat request in data link layer to provide error free communication, (c) the presented schemes are designed based on imperfect signal-to-noise ratio (SNR) estimate of the links. In addition to an analytical approach, a JSL scheme based on sub-gradient projection (JSL-SP) is presented in which there is no need to have SNRs probability density functions. Numerical results demonstrate how the proposed JSL schemes outperforms the benchmark schemes and effectively meets various user's requirements.

关键词： telecommunication scheduling radio links delays automatic repeat request delay constrained throughput optimised joint scheduling link adaptation scheme imperfect channel state information wireless links packet error rate delay constraints utility based scheduling schemes statistical bound queuing delay behaviour adaptive modulation and coding PER constraint H automatic repeat request data link layer signal-to-noise ratio SNR JSL scheme sub-gradient projection

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Classification of Error Correcting Codes and Estimation of Interleaver Parameters in a Noisy Transmission Environment

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IEEE TRANSACTIONS ON BROADCASTING 2017年第3期63卷 463-478页

作者： Swaminathan, R. Madhukumar, A. S. Nanyang Technol Univ Sch Comp Sci & Engn Singapore 639798 Singapore

Channel encoder, which includes a forward error correcting (FEC) code followed by an interleaver, plays a vital role in improving the error performance of digital storage and communication systems. In most of the applications, the FEC code and interleaver parameters are known at the receiver to decode and de-interleave the information bits, respectively. But the blind/semi-blind estimation of code and interleaver parameters at the receiver will provide additional advantages in applications, such as adaptive modulation and coding, cognitive radio, non-cooperative systems, etc. The algorithms for the blind estimation of code parameters at the receiver had previously been proposed and investigated for known FEC codes. In this paper, we propose algorithms for the joint recognition of the type of FEC codes and interleaver parameters without knowing any information about the channel encoder. The proposed algorithm classify the incoming data symbols among block coded, convolutional coded, and uncoded symbols. Further, we suggest analytical and histogram approaches for setting the threshold value to perform code classification and parameter estimation. It is observed from the simulation results that the code classification and interleaver parameter estimation are performed successfully over erroneous channel conditions. The proposed histogram approach is more robust against the analytical approach for noisy transmission environment and system latency is one of the important challenges for the histogram approach to achieve better performance.

关键词： adaptive modulation and coding blind/semiblind estimation block interleaver cognitive radio forward error correcting (FEC) code

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Nonlinearity-Tolerant Four-Dimensional 2A8PSK Family for 5-7 Bits/Symbol Spectral Efficiency

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JOURNAL OF LIGHTWAVE TECHNOLOGY 2017年第8期35卷 1383-1391页

作者： Kojima, Keisuke Yoshida, Tsuyoshi Koike-Akino, Toshiaki Millar, David S. Parsons, Kieran Pajovic, Milutin Arlunno, Valeria Mitsubishi Elect Res Labs Cambridge MA 02139 USA Acacia Commun Maynard MA 01754 USA Chalmers Univ Technol Dept Microtechnol & Nanosci SE-41296 Gothenburg Sweden

We describe in detail the recently proposed four-dimensional modulation format family based on 2-ary amplitude 8-ary phase-shift keying (2A8PSK), supporting spectral efficiencies of 5, 6, and 7 bits/symbol. These formats nicely fill the spectral efficiency gap between the dual-polarization (DP) quadrature PSK (QPSK) and DP 16-ary quadrature-amplitude modulation (16QAM), with excellent linear and nonlinear performance. Since these modulation formats just use different parity bit expressions in the same constellation, similar digital signal processing can be seamlessly used for different spectral efficiency. A series of nonlinear transmission simulation results shows that this modulation format family outperforms the conventional modulation formats at the corresponding spectral efficiency. We also investigate the adaptive equalizer for these modulation formats.

关键词： adaptive modulation and coding high-dimensional modulation format nonlinearity tolerance spectral efficiency

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Cross-Layer QoS-Constrained Optimization of adaptive Multi-Rate Wireless Systems using Infrastructure-Based Cooperative ARQ

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2013年第5期12卷 2424-2435页

作者： Ramis, Jaume Femenias, Guillem Univ Balearic Isl Mobile Commun Grp Mallorca 07122 Illes Balears Spain

This research work aims at analyzing the effects of using cooperative-ARQ (CARQ) in wireless relay systems employing AMC at the physical layer and an infinitely persistent type-I Hybrid FEC/CARQ protocol at the DLC layer. To that end, a cross-layer multidimensional discrete-time Markov chain (DTMC)-based queuing model is developed to jointly exploit the capabilities of CARQ and AMC. Based on the stationary state probability distribution of the proposed multidimensional DTMC, closed-form analytical expressions for performance metrics such as average throughput, queue length, packet delay and packet loss rate are derived, and the impact of cooperative relaying on these performance parameters is analyzed. Numerical results confirm the validity of the presented AMC/CARQ cross-layer analytical framework and reveal that the proposed CARQ protocol consistently outperforms the classical Type-I Hybrid FEC/ARQ schemes and provides a noticeable improvement when facing correlated fading channel scenarios.

关键词： adaptive modulation and coding cooperative automatic repeat request Markov models cross-layer design

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Investigation on Optimum Control Interval for Intra-Cell Fractional TPC Using AMC for Shared Channel in Evolved UTRA Uplink

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IEICE TRANSACTIONS ON COMMUNICATIONS 2009年第5期E92B卷 1627-1633页

作者： Nishikawa, Daisuke Kishiyama, Yoshihisa Higuchi, Kenichi Sawahashi, Mamoru NTT DOCOMO INC Radio Access Network Dev Dept Yokosuka Kanagawa 2398536 Japan Tokyo Univ Sci Dept Elect Sci Noda Chiba 2788510 Japan Musashi Inst Technol Dept Informat Network Engn Tokyo 1588557 Japan

This paper presents the optimum control interval for intra-cell fractional transmission power control (TPC) for a shared data channel employing frequency domain channel-dependent scheduling and adaptive modulation and coding (AMC) in the Evolved UTRA uplink using single-carrier (SC)-FDMA radio access. The simulation results show that the best attenuation factor in the fractional TPC is approximately 0.6 for achieving the maximum user throughput when the maximum target received signal Power, P-0 is -60dBm. Then, we show that the optimum averaging interval for the desired signal level. which corresponds to a Substantial control interval for the fractional TPC is approximately 100-200 msec regardless of the maximum Doppler frequency up to 222 Hz and the distance at the shadowing correlation of 0.5. Throughout the simulation results, we verify that slow intra-cell fractional TPC associated with Fast AMC is effective in achieving the maximum cell throughput and cell-edge user throughput.

关键词： Evolved UTRA fractional transmission power control adaptive modulation and coding uplink

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An efficient scheduling scheme with diverse traffic demands in IEEE 802.16 networks

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WIRELESS COMMUNICATIONS & MOBILE COMPUTING 2010年第7期10卷 959-971页

作者： Hou, Fen Ho, Pin-Han Shen, Xuemin (Sherman) Univ Waterloo Dept Elect & Comp Engn Waterloo ON N2L 3G1 Canada

In IEEE 802.16 networks, a subscriber station (SS) could be a single mobile user, a residence house, or an office building providing Internet service for multiple customers. Considering the heterogeneity among SSs which have diverse traffic demands, in this paper, we introduce the weighted proportional fair (WPF) scheduling scheme for the Best Effort (BE) service in IEEE 802.16 networks to achieve the flexible and efficient resource allocation. We develop an analytical model to investigate the performance of WPF in terms of spectral efficiency, throughput, resource utilization, and fairness, where the Rayleigh fading channel and the adaptive modulation and coding (AMC) technique are considered. Extensive simulations are conducted to illustrate the efficiency of the WPF scheduling scheme and verify the accuracy of the analytical model. Copyright (C) 2009 John Wiley & Sons, Ltd.

关键词： weighted proportional fair scheduling IEEE 802.16 adaptive modulation and coding fairness

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Performance analysis of HARQ protocols with link adaptation on fading channels

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ANNALS OF TELECOMMUNICATIONS-ANNALES DES TELECOMMUNICATIONS 2011年第11-12期66卷 695-705页

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

This work considers hybrid automatic repeat request (HARQ) protocols on a fading channel with Chase combining and deals with both Rayleigh and Nakagami-m fading. We derive the packet loss probability and the throughput for HARQ both for a slow-varying and a fast-varying channel. We then consider link adaptation with complete channel state information (CSI) for which the instantaneous signal-to-noise ratio (SNR) is known and with incomplete CSI for which only the average SNR is known. We derive analytical formulae of the long-term throughput. These formulae are simple enough to be used for higher level simulations. We show that the throughput is slightly higher on a slow-varying channel but at the expense of a higher loss probability.

关键词： Hybrid automatic repeat request adaptive modulation and coding Cross-layer design Wireless networks Fading channels

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Quality of Service Provisioning and Energy Minimized Scheduling in Software Defined Flexible Optical Networks

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JOURNAL OF OPTICAL COMMUNICATIONS AND NETWORKING 2016年第2期8卷 118-128页

作者： Khodakarami, Hamid Pillai, Bipin Sankar Gopalakrishna Shieh, William Univ Melbourne CEET Parkville Vic 3010 Australia Univ Melbourne Dept Elect & Elect Engn Parkville Vic 3010 Australia

The over-provisioning of capacities in optical networks is not a sustainable approach in the long run. In this paper, we propose a software defined networking scheme for quality of service provisioning through energy efficient assignment of optical transponders, employing bandwidth variable distance adaptive modulation and coding. Our scheme enables avoiding over-provisioning of transponder capacity as well as short-term major changes in equipment allocation for networks with dynamic traffic. We make use of the seasonal auto-regressive integrated moving average model to forecast the statistics of network traffic for an arbitrary time span based on the requirements and the constraints of the service provider. The quality of service measure is defined as the probability of congestion at the core router ports. A stochastic linear programming approach is used to provide a solution for energy efficient assignment of optical transponders and electronic switching capacity while ensuring a certain level of quality of service to core routers. The scheduling of optical lightpath capacities is performed for the entire duration of time under consideration, whereas the scheduling of electronic switching capacities is performed based on the short-term dynamics of the traffic. Numerical results show up to 48% improvement in the energy efficiency of optical networks and 45% reduction in the number of optical lightpaths through the implementation of the proposed technique, compared to a design based on employing conventional fixed optical transponders and no traffic rerouting, where both schemes satisfy the congestion probability requirements.

关键词： adaptive modulation and coding Electronic switching Energy efficiency Flexible optical transponders Low density parity check codes Network scheduling Optical communications Optical networks Orthogonal frequency division multiplexing Quality of service Software defined networks Traffic grooming

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Layered Resource Allocation for Video Broadcasts over Wireless Networks

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IEEE TRANSACTIONS ON CONSUMER ELECTRONICS 2008年第4期54卷 1609-1616页

作者： Kim, Junu Cho, Jinsung Shin, Heonshik Seoul Natl Univ Sch Engn & Comp Sci Seoul 151 South Korea Kyung Hee Univ Dept Comp Engn Yongin 446701 South Korea

This paper aims to combine adaptive modulation and coding with layered video coding to improve the quality of video services to users experiencing differing radio conditions, in the context of broadcast and multicast standards such as MBMS and BCMCS. We propose an optimal radio resource allocation algorithm which maximizes a general performance metric for a video session in polynomial time. We show that system-wide optimal resource allocation can be obtained by combining our algorithm with a simple two-step decomposition of the system. In some configurations frequent re-allocations of resource are required, so we also present a sub-optimal allocation algorithm which runs in near linear time. Simulation results show better video quality than existing resource allocation schemes over a range of conditions, and also suggest that the difference between the performance of optimal and suboptimal solutions is less than 3%(1).

关键词： radio resource allocation wireless video broadcast layered video coding adaptive modulation and coding

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Energy-Efficient Video Multicast in 4G Wireless Systems

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IEEE TRANSACTIONS ON MOBILE COMPUTING 2012年第10期11卷 1508-1522页

作者： Yu, Ya-Ju Hsiu, Pi-Cheng Pang, Ai-Chun Natl Taiwan Univ Grad Inst Networking & Multimedia Taipei 106 Taiwan Acad Sinica Res Ctr Informat Technol Innovat CITI Taipei 115 Taiwan Acad Sinica IIS Taipei 115 Taiwan Natl Taiwan Univ Grad Inst Networking & Multimedia Taipei 106 Taiwan Natl Taiwan Univ Dept Comp Sci & Informat Engn Taipei 106 Taiwan

Layer-based video coding, together with adaptive modulation and coding, is a promising technique for providing real-time video multicast services on heterogeneous mobile devices. With the rapid growth of data communications for emerging applications, reducing the energy consumption of mobile devices is a major challenge. This paper addresses the problem of resource allocation for video multicast in fourth-generation wireless systems, with the objective of minimizing the total energy consumption for data reception. First, we consider the problem when scalable video coding is applied. We prove that the problem is NP-hard and propose a 2-approximation algorithm to solve it. Then, we investigate the problem under multiple description coding, and show that it is also NP-hard and cannot be approximated in polynomial time with a ratio better than 2, unless P = NP. To solve this case, we develop a pseudopolynomial time 2-approximation algorithm. The results of simulations conducted to compare the proposed algorithms with a brute-force optimal algorithm and a conventional approach are very encouraging.

关键词： Energy efficiency video multicast scalable video coding multiple description coding adaptive modulation and coding 4G wireless systems

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