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

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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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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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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Distributed Scalar Quantizers for Subband Allocation

Distributed Scalar Quantizers for Subband Allocation

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48th Annual Conference on Information Sciences and Systems (CISS)

作者： Boyle, Bradford D. Walsh, John MacLaren Weber, Steven Drexel Univ Dept Elect & Comp Engn Philadelphia PA 19104 USA

ISBN: (纸本)9781479930012

Efficient downlink resource allocation (e.g., subbands in OFDMA/LTE) requires channel state information (e.g., subband gains) local to each user be transmitted to the base station (BS). Lossy encoding of the relevant state may result in suboptimal resource allocations by the BS, the performance cost of which may be captured by a suitable distortion measure. This problem is an indirect distributed lossy source coding problem with the function to be computed representing the optimal resource allocation, and the distortion measuring the cost of suboptimal allocations. In this paper we investigate the use of distributed scalar quantizers for lossy encoding of state, where the BS wishes to compute the index of the user with the largest gain on each subband. We prove the superiority of a heterogeneous (across users) quantizer design over the optimal homogeneous quantizer design, even though the source variables are i.i.d.

关键词： Quantization rateless coding adaptive modulation and coding resource allocation

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System-Level Performance of Downlink NOMA Combined with SU-MIMO for Future LTE Enhancements

System-Level Performance of Downlink NOMA Combined with SU-M...

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IEEE Global Communications Conference (GLOBECOM)

作者： Benjebbour, Anass Li, Anxin Kishiyama, Yoshihisa Jiang, Huiling Nakamura, Takehiro NTT DOCOMO INC Radio Access Network Dev Dept Tokyo Tokyo Japan DOCOMO Beijing Commun Labs Co Ltd Beijing Peoples R China

ISBN: (纸本)9781479974702

This paper investigates the system-level performance of downlink non-orthogonal multiple access (NOMA) combined with single user MIMO (SU-MIMO) for future LTE (Long-Term Evolution) enhancements. The goal is to clarify the performance gains of NOMA combined with SU-MIMO transmission, taking into account the LTE radio interface such as frequency-domain scheduling, adaptive modulation and coding (AMC), and NOMA specific functionalities such as multi-user pairing/ordering and transmit power allocation. In particular, we propose practical schemes to efficiently combine NOMA with open-loop SU-MIMO (Transmission Mode 3: TM3) and closed-loop SU-MIMO (Transmission Mode 4: TM4) specified in LTE. Based on computer simulations, we compare NOMA performance gains for different granularities of scheduling and MCS (modulation and coding scheme) selection, for both genie-aided channel quality information (CQI) estimation and approximated CQI estimation, and using different number of power sets. Evaluation results show that NOMA can still provide a hefty portion of its expected gains even with approximated CQI estimation and limited number of power sets, and also when LTE compliant subband scheduling and wideband MCS are applied.

关键词： LTE NOMA MIMO superposition successive interference cancellation adaptive modulation and coding

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Investigation on Feedback Channel State Information for Interference Rejection Combining Receiver in LTE-Advanced Downlink 79

Investigation on Feedback Channel State Information for Inte...

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IEEE 79th Vehicular Technology Conference (VTC-Spring)

作者： Sano, Yousuke Ohwatari, Yusuke Sagae, Yuta Morimoto, Akihito Okumura, Yukihiko NTT DOCOMO INC Yokosuka Kanagawa 2398536 Japan

ISBN: (纸本)9781479944828

This paper investigates a scheme for deriving feedback information for the interference rejection combining (IRC) receiver, which can suppress inter-cell interference, in order to perform adaptive modulation and coding (AMC), user scheduling, and transmission precoding at the serving eNodeB appropriately in the LTE/LTE-Advanced downlink. In this paper, we evaluate the negative impact of inappropriate feedback information for the IRC receiver, i.e., not including the interference suppression effect, and the effectiveness of appropriate feedback information on the user throughput performance. Simulation results assuming two transmitter/receiver antenna branches and an uncorrelated channel show that interference suppression for the IRC receiver does not affect the precoding matrix selection when selecting a common precoding matrix for the transmission bandwidth. Furthermore, even when the IRC receiver calculates the feedback information excluding the effect of interference suppression, the user throughput improves compared to that for the conventional MMSE receiver, which cannot suppress the inter-cell interference. However, when comparing the performance of the IRC receivers that calculate the feedback information when including and excluding the effect of interference suppression, the results show that the degree of improvement in the user throughput when excluding the interference suppression effect degrades due to inappropriate feedback information.

关键词： Long Term Evolution interference suppression radio receivers receiving antennas transmitting antennas IRC receiver LTE-advanced downlink MMSE receiver adaptive modulation and coding feedback channel state information intercell interference suppression interference rejection combining receiver precoding matrix selection receiver antenna branch transmission bandwidth transmission precoding transmitter antenna branch user scheduling Channel estimation Covariance matrices Interference suppression Receivers Signal to noise ratio suppression of interference Long Term Evolution feedback information Receivers transmission bandwidth signal to noise ratios transmitting antennas Receiving antennas infrared photocoagulation therapy Internet Relay Chat radio receivers channel estimation

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Bandwidth Allocation for QoS Using adaptive modulation and coding in IEEE 802.16 Networks

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IEICE TRANSACTIONS ON COMMUNICATIONS 2009年第12期E92B卷 3919-3922页

作者： Jo, Hyun-Wook Jeon, Jae-Han Lim, Jong-The Korea Adv Inst Sci & Technol Dept Elect Engn Taejon 305701 South Korea

In recent years, there have been many studies on integrating a number of heterogeneous wireless networks into one network by establishing standards like IEEE 802.16. For this purpose, the base station (BS) should allocate the appropriate bandwidth to each connection with a network scheduler. In wireless networks, the signal to noise ratio (SNR) changes with time due to many factors such as fading. Hence, we estimate the SNR based oil the error rate reflecting wireless network condition. Using the estimated SNR, we propose a new time slot allocation algorithm so that the proposed algorithm guarantees the delay requirement and full link utilization.

关键词： QoS SNR bandwidth allocation adaptive modulation and coding

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Throughput Analysis of Best-m Feedback in OFDM Systems with Uniformly Correlated Subchannels

Throughput Analysis of Best-<i>m</i> Feedback in OFDM System...

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20th National Conference on Communications (NCC)

作者： Ananya, S. N. Mehta, Neelesh B. Indian Inst Sci IISc Dept Elect Commun Engn Bangalore Karnataka India

ISBN: (纸本)9781479923618

Practical orthogonal frequency division multiplexing (OFDM) systems, such as Long Term Evolution (LTE), exploit multi-user diversity using very limited feedback. The best-m feedback scheme is one such limited feedback scheme, in which users report only the gains of their m best subchannels (SCs) and their indices. While the scheme has been extensively studied and adopted in standards such as LTE, an analysis of its throughput for the practically important case in which the SCs are correlated has received less attention. We derive new closed-form expressions for the throughput when the SC gains of a user are uniformly correlated. We analyze the performance of the greedy but unfair frequency-domain scheduler and the fair round-robin scheduler for the general case in which the users see statistically non-identical SCs. An asymptotic analysis is then developed to gain further insights. The analysis and extensive numerical results bring out how correlation reduces throughput.

关键词： Orthogonal frequency division multiplexing (OFDM) Correlation Channel quality feedback Best-m Frequency-domain scheduling adaptive modulation and coding

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A QoS-aware and adaptive Soft Frequency Reuse Scheme for Interference Coordination in MMN 14

A QoS-aware and Adaptive Soft Frequency Reuse Scheme for Int...

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IEEE International Conference on Computer and Information Technology (CIT 2014)

作者： Wang, Yuanshuang Wang, Xia Shi, Jun Xi An Jiao Tong Univ Sch Elect & Informat Engn Xian Shaanxi Peoples R China

ISBN: (纸本)9781479962396

This paper proposes an adaptive soft frequency reuse (ASFR) scheme for inter-cell interference coordination in mobile multimedia networks (MMN). We first set up the resource allocation model of MMN within LTE framework. adaptive modulation and coding (AMC) and maximum throughput (MT) algorithm are employed to complete the system model among 19 cells. Then we design the intra-cell handover mechanism in terms of different quality of service (QoS) requirements to implement ASFR and only limited information needs to be exchanged within a base station. The proposed scheme can adaptively vary the spectrum and power allocation of major and minor subcarriers for each cell according to traffic loads. Simulation results show that the adaptive scheme can obtain a better tradeoff between system throughput and cell coverage compared with conventional SFR schemes.

关键词： soft frequency reuse adaptive modulation and coding maximum throughput interference coordination

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Spectral Efficiency Analysis for LTE Networks 4

Spectral Efficiency Analysis for LTE Networks

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4th IEEE International Conference on Consumer Electronics Berlin (ICCE-Berlin)

作者： Chen, Wen-Tzu Natl Cheng Kung Univ Inst Telecommun Management Tainan Taiwan

ISBN: (纸本)9781479961658

This paper analyzes the uplink spectrum efficiency of an LTE network, taking intercell co-channel interference into account. This study is based on signal-to-interference-plus-noise ratio analysis and appropriate channel models including path loss and shadow fading. This paper also uses the proportional fair scheduling scheme to allocate resource blocks to improve the cell edge performance. The research results reveal that the intercell co-channel interference can cause up to 50% throughput reduction for cell edge users, but has almost no impact on cell centric user performance.

关键词： spectral efficiency LTE co-channel interference adaptive modulation and coding resource allocation

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