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

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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Joint Physical-Layer and System-Level Power Management for Delay-Sensitive Wireless Communications

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IEEE TRANSACTIONS ON MOBILE COMPUTING 2013年第4期12卷 694-709页

作者： Mastronarde, Nicholas van der Schaar, Mihaela SUNY Buffalo Dept Elect Engn Buffalo NY 14260 USA Univ Calif Los Angeles Dept Elect Engn Los Angeles CA 90095 USA

We consider the problem of energy-efficient point-to-point transmission of delay-sensitive data (e. g., multimedia data) over a fading channel. Existing research on this topic utilizes either physical-layer centric solutions, namely power-control and adaptive modulation and coding (AMC), or system-level solutions based on dynamic power management (DPM);however, there is currently no rigorous and unified framework for simultaneously utilizing both physical-layer centric and system-level techniques to achieve the minimum possible energy consumption, under delay constraints, in the presence of stochastic and a priori unknown traffic and channel conditions. In this paper, we propose such a framework. We formulate the stochastic optimization problem as a Markov decision process (MDP) and solve it online using reinforcement learning (RL). The advantages of the proposed online method are that 1) it does not require a priori knowledge of the traffic arrival and channel statistics to determine the jointly optimal power-control, AMC, and DPM policies;2) it exploits partial information about the system so that less information needs to be learned than when using conventional reinforcement learning algorithms;and 3) it obviates the need for action exploration, which severely limits the adaptation speed and runtime performance of conventional reinforcement learning algorithms. Our results show that the proposed learning algorithms can converge up to two orders of magnitude faster than a state-of-the-art learning algorithm for physical layer power-control and up to three orders of magnitude faster than conventional reinforcement learning algorithms.

关键词： Energy-efficient wireless communications dynamic power management power-control adaptive modulation and coding Markov decision process reinforcement learning

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Delay-Aware Energy-Efficient Communications Over Nakagami-m Fading Channel With MMPP Traffic

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IEEE TRANSACTIONS ON COMMUNICATIONS 2015年第8期63卷 3008-3020页

作者： Wang, Kunlun Tao, Meixia Chen, Wen Guan, Quansheng Shanghai Jiao Tong Univ Dept Elect Engn Shanghai 200240 Peoples R China S China Univ Technol Sch Elect & Informat Engn Guangzhou 510640 Guangdong Peoples R China

In this paper, we propose a cross-layer design framework for transmitting Markov modulated Poisson process (MMPP) traffic over Nakagami-m fading channel with delay demands. The adaptive modulation and coding (AMC) technique is used at the physical layer. The energy efficiency is described as the average throughput over the average transmission power, where both of throughput and transmit power have full consideration of the queuing system. We first derive the closed-form expressions of the delay and the energy efficiency with the stationary distribution of the system. We then derive the energy efficient thresholds to choose the AMC transmission modes. At last, we derive the transmission policy to maximize the energy efficiency with delay constraints. Numerical results are provided to support the theoretical development.

关键词： Cross-layer design energy efficiency adaptive modulation and coding queuing theory finite state Markov channel Markov modulated Poisson process delay

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adaptive QoS provision for IEEE 802.16e BWA networks based on cross-layer design

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EURASIP JOURNAL ON WIRELESS COMMUNICATIONS AND NETWORKING 2011年第1期2011卷 1-16页

作者： Zhang, Hongtao Wang, Xiaoxiang Qin, Z. B. Kuo, G. S. Bohnert, Thomas Michael Beijing Univ Posts & Telecommun Minist Educ Key Lab Universal Wireless Commun Beijing 100876 Peoples R China Natl Chengchi Univ Taipei 11623 Taiwan SAP Res CEC Zurich Switzerland

This article proposes an integrated framework for adaptive QoS provision in IEEE 802.16e broadband wireless access networks based on cross-layer design. On one hand, an efficient admission control (AC) algorithm is proposed along with a semi-reservation scheme to guarantee the connection-level QoS. First, to guarantee the service continuity for handoff connections and resource efficiency, our semi-reservation scheme considers both users' handoff probability and average resource consumption together, which effectively avoids resource over-reservation and insufficient reservation. For AC, a new/handoff connection is accepted only when the target cell has enough resource to afford both instantaneous and average resource consumption to meet the average source rate request. On the other hand, a joint resource allocation and packet scheduling scheme is designed to provide packet-level QoS guarantee in term of "QoS rate", which can ensure fairness for the services with identical priority level in case of bandwidth shortage. Particularly, an enhanced bandwidth request scheme is designed to reduce unnecessary BR delay and redundant signaling overhead caused by the existing one in IEEE 802.16e, which further improves the packet-level QoS performance and resource efficiency for uplink transmission. Simulation results show that the proposed approach not only balances the tradeoff among connection blocking rate, connection dropping rate, and connection failure rate, but also achieves low mean packet dropping rate (PDR), small deviation of PDR, and low QoS outage rate. Moreover, high resource efficiency is ensured.

关键词： IEEE 802.16e QoS model cross-layer design adaptive modulation and coding admission control resource reservation bandwidth allocation scheduling bandwidth request

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Cross-layer-based adaptive TCP algorithm for cloud computing services in 4G LTE-A relaying communication

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WIRELESS NETWORKS 2016年第8期22卷 2579-2595页

作者： Chang, Ben-Jye Li, Yi-Hsuan Chen, Shin-Pin Liang, Ying-Hsin Natl Yunlin Univ Sci & Technol Dept Comp Sci & Informat Engn Yunlin Taiwan Nan Kai Univ Technol Dept Multimedia Animat & Applicat Nantou Taiwan

Cloud computing provides various diverse services for users accessing big data through high data rate cellular networks, e.g., LTE-A, IEEE 802.11ac, etc. Although LTE-A supports very high data rate, multi-hop relaying, and cooperative transmission, LTE-A suffers from high interference, path loss, high mobility, etc. Additionally, the accesses of cloud computing services need the transport layer protocols (e.g., TCP, UDP, and streaming) for achieving end-to-end transmissions. Clearly, the transmission QoS is significantly degraded when the big data transmissions are done through the TCP protocol over a high interference LTE-A environment. The issue of providing high data rate and high reliability transmissions in cloud computing needs to be addressed completely. Thus, this paper proposes a cross-layer-based adaptive TCP algorithm to gather the LTE-A network states (e.g., AMC, CQI, relay link state, available bandwidth, etc.), and then feeds the state information back to the TCP sender for accurately executing the network congestion control of TCP. As a result, by using the accurate TCP congestion window (cwnd) under a high interference LTE-A, the number of timeouts and packet losses are significantly decreased. Numerical results demonstrate that the proposed approach outperforms the compared approaches in goodput and fairness, especially in high interference environment. Especially, the goodput of the proposed approach is 139.42 % higher than that of NewReno when the wireless loss increases up to 4 %. Furthermore, the throughput and the response functions are mathematically analyzed. The analysis results can justify the claims of the proposed approach.

关键词： LTE-A Multiple-hop relaying Cross-layer adaptive modulation and coding Congestion control TCP reliable transmission

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Joint Connection Level and Packet Level Analysis of Cognitive Radio Networks with VoIP Traffic

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IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 2014年第3期32卷 601-614页

作者： Lirio Castellanos-Lopez, Sandra Cruz-Perez, Felipe A. Rivero-Angeles, Mario E. Hernandez-Valdez, Genaro IPN CINVESTAV Dept Elect Engn Mexico City 07738 DF Mexico IPN UPIITA Telemat Dept Mexico City 07738 DF Mexico UAM A Dept Elect Mexico City DF Mexico

In this paper, a novel joint connection-level and packet-level analytical model for the performance evaluation of cognitive radio networks (CRNs) under VoIP traffic is proposed and developed. The proposed teletraffic model captures the most relevant features of both CRNs (i.e., unreliable spectrum sensing, primary users' activity detection) and VoIP traffic (i.e., ON/OFF activity processes for individual VoIP sessions, periodic packet generation of individual VoIP sessions in the ON state). In addition, our mathematical model captures relevant aspects of multiuser VoIP-based networks such as the use of packet buffering, adaptive modulation coding, proportional fair sharing scheduling for secondary users with different link qualities, and call admission control (CAC). Our mathematical analysis is based on the time-scale decomposition technique and employs conventional discrete time Markov chain tools. However, the most important feature of our mathematical formulation is the introduction of the so called cross-level analysis methodology used here to link packet-level and connection-level analyses. This proposed methodology allows to use time-scale decomposition technique when it is no longer possible to perform the connection level analysis in an independent manner from the packet level analysis (i.e., when connection level statistics depend on packet level parameters).

关键词： Cognitive radio networks joint connection level and packet level teletraffic analysis on/off VoIP traffic unreliable spectrum sensing call admission control adaptive modulation and coding packet buffering

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Discrete Rate Interfering Cognitive Link Adaptation Design with Primary Link Spectral Efficiency Provisioning

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2011年第9期10卷 2929-2939页

作者： Taki, Mehrdad Lahouti, Farshad Univ Tehran Sch Elect & Comp Engn Ctr Excellence Appl Electromagnet Syst Wireless Multimedia Commun LabColl Engn Tehran 14395515 Iran

We consider a primary and a cognitive user transmitting over a wireless fading interference channel. A discrete rate link adaptation scheme is proposed to maximize the average spectral efficiency of the cognitive radio, while a minimum average spectral efficiency for the primary user is provisioned. The discrete rate scheme for interfering transmission is devised based on two sets of modulation and coding pairs for the primary and cognitive links. The primary transmitter adapts its rate (modulation and coding) solely based on signal to interference plus noise ratio of its link;however, the cognitive transmitter influences the primary link rate by imposing a proper SINR. The adaptive modulation and coding mode selection and power control at the cognitive transmitter are optimized based on SINR of both links. The problem is then cast as a nonlinear discrete optimization problem for which a fast and efficient suboptimum solution is presented. We also present a scheme with rate adaptive and constant power cognitive radio. An important characteristic of the proposed schemes is that no computation overhead is imposed on primary radio due to cognitive radio activity. Numerical results and comparison with the interweave approach to cognitive radio demonstrate the efficiency of the proposed solutions.

关键词： Cognitive radio adaptive modulation and coding power control interfering transmission

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Effective capacity optimization for multiuser diversity systems with adaptive transmission

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TRANSACTIONS ON EMERGING TELECOMMUNICATIONS TECHNOLOGIES 2012年第6期23卷 567-584页

作者： Harsini, Jalil S. Lahouti, Farshad Univ Guilan Dept Elect Engn Rasht Iran Univ Tehran Sch Elect & Comp Engn Wireless Multimedia Commun Lab Ctr Excellence Appl Electromagnet Syst Tehran Iran

The effective capacity (EC) for a wireless system expresses the maximum arrival source rate that the system can reliably transmit over the wireless channel while fulfilling a probabilistic delay constraint. This paper presents an EC optimization for a multiuser diversity system exploiting proportional opportunistic scheduling at the medium access control layer in conjunction with adaptive modulation and coding (AMC) at the physical layer. We consider the downlink of a time-slotted multiuser system with two different types of channel state information (CSI) at the transmitter, that is, (i) full CSI, whereby each user feeds back its normalized signal-to-noise ratio to the transmitter and (ii) quantized CSI, where each user feeds back the AMC mode for transmission. For each case, we first derive the EC function of the queue service process for the individual users at the medium access control layer. We then design the AMC scheme with power control aiming at maximizing the said function subject to a target packet-error rate constraint. Both independent and identically distributed and time-correlated fading channels are considered. The results illustrate the superior performance of the proposed schemes, when compared with the previous systems such as opportunistic scheduling with single-rate transmission and round-robin scheduling with AMC. Copyright (c) 2012 John Wiley & Sons, Ltd.

关键词： proportional fairness scheduling adaptive modulation and coding effective capacity cross-layer optimization resource allocation

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Delay constrained throughput optimization in multi-hop AF relay networks, using limited quantized CSI

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EURASIP JOURNAL ON WIRELESS COMMUNICATIONS AND NETWORKING 2019年第1期2019卷 1页

作者： Taki, Mehrdad Svensson, Tommy Nezafati, Mohammad Bagher Univ Qom Dept Elect Engn Qom Iran Chalmers Univ Technol Dept Signals & Syst Gothenburg Sweden Inst Res Fundamental Sci Tehran Iran

In this paper, we analyze the throughput of multi-hop amplify and forward (AF) relay networks in delay-constrained scenario. Using quantized channel state information (CSI), the transmission rates and powers are discretely adapted with individual average power constraint on each node. A sub-gradient projection-based algorithm is utilized, by which there is no need for probability density functions (PDFs) to solve the optimization problem. Our numerical evaluations show that the sub-gradient projection-based algorithm results in a comparable performance with an analytical approach using PDFs. As shown, a considerably better performance obtained by the designed scheme compared to previous schemes with constant power transmission. More than 70% throughput improvement is achieved by our scheme compared to constant power transmission with just two more feedback bits and a short training time required at the beginning of the transmission.

关键词： Multi-hop relay Amplify and forward relaying Discrete link adaptation adaptive modulation and coding Delay-QoS constraint

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Application-Aware MCS Level Selection Method for Cross-Layered Retransmission Scheme

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IEEE COMMUNICATIONS LETTERS 2014年第2期18卷 209-212页

作者： Go, Kwang-Chun Kim, Jae-Hyun Ajou Univ Dept Elect & Comp Engn Suwon 441749 South Korea

In this letter, we propose an application-aware modulation and coding scheme (MCS) level selection method for a cross-layered retransmission scheme. The existing MCS level selection methods use fixed target packet error rate (PER) only and do not take into account quality of service (QoS) requirements for an application. This may cause a discrepancy between the QoS requirements of an application and the criterion for selection of an MCS level. Therefore, the channel utilization is decreased due to the discrepancy. To remove the discrepancy, the application-aware MCS level selection method adjusts a target PER according to the type of application. We have shown that the proposed scheme can improve the wireless channel utilization.

关键词： adaptive modulation and coding application-aware cross-layer retransmission channel utilization

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