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SoftHM: A Software-Based Hierarchical modulation Design for Wireless System

IEEE-ACM TRANSACTIONS ON NETWORKING 2021年第1期29卷 452-464页

作者： Chen, Weiwei Liu, Yunhuai He, Tian Southeast Univ Dept Comp & Elect Engn Nanjing 214135 Peoples R China Peking Univ Big Data Res Ctr Beijing 100871 Peoples R China

Hierarchical modulation (HM) is quite efficient for multimedia broadcast in wireless networks. It exploits the wireless broadcast advantage and allows a transmission to reach different users with various qualities. However, existing HM related schemes are based on specially designed hardware, leading to extra hardware and deployment cost in practice. As a remedy for this, we design and implement a software-based HM scheme, named as SoftHM. By carefully tuning the Physical Layer input of a packet (a sequence of "0" or "1" bits, known as PHY payload), a transmitter simply broadcasts the packet with a single rate (e.g., 54Mbps, the highest rate in 802.11g WLAN), while diverse receivers can decode and extract different amount of information (with different reception rate, e.g., 12Mbps or 54Mbps) from it based on their link qualities. Reverse engineering techniques are adopted so that SoftHM works in a plug-in mode, offering it high potentials for wireless systems without any changes in existing modulation and coding modules. We implement SoftHM based on Universal Software Radio Peripheral (USRP) B210 and Commercial of the Shelf (COTS) Wi-Fi devices. Both rigorous analysis on its performance and comprehensive implementation-based experiments show that compared with the traditional time-sharing approach, to support low-quality users with the same bandwidth, high-quality users in SoftHM achieve 111.1% to 616.7% higher throughput. Likewise, to serve high-quality users with the same bandwidth, low quality users in softHM achieve 176.9% to 390.9% higher throughput.

关键词： modulation Encoding Receivers Streaming media Wireless fidelity Binary phase shift keying Payloads Hierarchical modulation signal emulation mobile communication system PHY layer payload design modulation and coding scheme

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Wireless link state-aware H.264 MGS coding-based mobile IPTV system over WiMAX network

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JOURNAL OF VISUAL COMMUNICATION AND IMAGE REPRESENTATION 2010年第2期21卷 89-97页

作者： Joo, Hyunchul Song, Hwangjun Pohang Univ Sci & Technol Pohang 790784 South Korea

This paper presents a simple but effective architecture for the transmission of H.264 MGS coding-based IPTV stream over WiMAX network. The proposed system is implemented to provide more subscribers with an enhanced mobile IPTV service considering their wireless link states. In the proposed system, the base layer of the IPTV stream is transmitted with the sparsest modulation scheme and the lowest coding rate to provide IPTV service of minimum quality to as many subscribers as possible. And some parts of the enhancement layer are transmitted with the modulation scheme and the coding rate adaptive to wireless link states of subscribers. Basically, we pursue an efficient tradeoff between the number of subscribers that receive the enhancement layer stream and their IPTV service quality. Finally, experimental results are provided to show the performance of the proposed system. (C) 2009 Elsevier Inc. All rights reserved.

关键词： Mobile IPTV WiMAX H.264 medium-grain scalability coding Media broadcasting IP multicast modulation and coding scheme Multicast and broadcast service Resource allocation

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MCS Selection Criteria Based on Performance Simulation for HSDPA

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Journal of Beijing Institute of Technology 2003年第4期12卷 407-411页

作者：杨小倩赵胜辉费泽松匡镜明 Department of Electronic Engineering

An adaptive modulation and coding (AMC) scheme integrated with multi-code transmission for high speed downlink packet access is presented and some modulation and coding scheme (MCS) selection criteria are proposed to maximize single user data rates. Based on link-level performance analysis, the MCS selection criteria are proposed with the constraints of QoS requirement, modulation level, channel coding rate and the number of available channelization codes. By allowing multiple transmission parameters changing, these criteria make the scheme more flexible to time-varying mobile channel with comparatively low complexity through a look-up table method. The AMC scheme is sensitive to the changes of channel condition and can save the channelization codes in an applicable way by applying these criteria.

关键词： high speed downlink packet access adaptive modulation and coding multi-code transmission modulation and coding scheme

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A Multi-Round Resources Allocation scheme for OFDMA-Based WiMAX Based on Multiple Service Classes

A Multi-Round Resources Allocation Scheme for OFDMA-Based Wi...

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International Conference on Information Science, Electronics and Electrical Engineering (ISEEE)

作者： Chen, Lishui Guo, Qing Wang, Junfang Liu, Guizhong China Elect Technol Grp Corp 54 Inst Shijiazhuang 050081 Peoples R China

ISBN: (纸本)9781479931972

IEEE 802.16 standard defines the broadband wireless access specification for WiMAX without any standardized schemes for resource allocation and scheduling, which has thus been attractive to researchers in the past few years. In this paper, a downlink resource allocation algorithm, named the Multi-Round Resource Allocation scheme, is proposed for OFDMA based PMP system in WiMAX networks based on multiple service classes. The algorithm allocates the wireless resource according to the channel states of each mobile station, the inherent priority of each service flow, the QoS requirements of the service flows, and the fairness among users as well as the fairness among the service flows. Simulation results show that the proposed algorithm has better performance in the average throughput, the average queuing delay, the loss rate and the fairness.

关键词： Multi-Round WiMAX OFDMA Resource Allocation Algorithm modulation and coding scheme

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Link-Level Performance Analysis of DVB Standards in Ultra-Dense LEO Satellite-Terrestrial Networks 99

Link-Level Performance Analysis of DVB Standards in Ultra-De...

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IEEE 99th Vehicular Technology Conference (VTC-Spring)

作者： Zhang, Xin Wang, Yilei Qin, Xiaohan Zhang, Zitian Zhou, Haibo Shen, Xuemin (Sherman) Nanjing Univ Sch Elect Sci & Engn Nanjing 210023 Peoples R China Zhejiang Gongshang Univ Sch Informat & Elect Engn Hangzhou 310018 Peoples R China Univ Waterloo Dept Elect & Comp Engn Waterloo ON N2L 3G1 Canada

ISBN: (纸本)9798350387414

Ultra-dense low earth orbit (LEO) satellite terrestrial networks (ULSNs) are considered as a crucial component of future six generation (6G) networks, offering ubiquitous and massive services for various applications. However, for the development of advanced physical layer technologies for ULSNs, a comprehensive link-level simulation tool that integrates up-to-date satellite communication protocols becomes paramount and is urgently needed. In this paper, we develop a versatile simulator for the link-level performance analysis of ULSNs under the prevalent digital video broadcasting (DVB) standards. We first establish a complete satellite-terrestrial microwave channel model, taking practical factors such as rain attenuation, cloud attenuation, and Doppler frequency shift into consideration. Subsequently, the whole physical layer modules tailored for satellite-terrestrial microwave communication are implemented, including diverse physical layer modulation and coding schemes (MCSs). Furthermore, we realize adaptive coding and modulation (ACM) for adaptive channel performance simulation. Finally, comparative performance analysis using the established channel model is conducted to demonstrate the effectiveness of different MCSs of DVB standards. The complete link-level performance analysis based on our self-developed simulator can advance the field of satellite-terrestrial microwave communication and provide valuable insights for further exploration of ULSNs.

关键词： Ultra-dense LEO satellite-terrestrial networks link-level simulation DVB protocol physical layer modulation and coding scheme

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The Airtime Resource Model Of The OFDM Channel In The Task Of The IEEE 802.11 Network Efficiency Estimation 10

The Airtime Resource Model Of The OFDM Channel In The Task O...

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10th International Congress on Ultra Modern Telecommunications and Control Systems and Workshops (ICUMT) - Emerging Technologies for Connected Society

作者： Vikulov, Anton Paramonov, Alexander Bonch Bruevich St Petersburg State Univ Telecommu Dept Commun Networks & Data Transmiss St Petersburg Russia

ISBN: (纸本)9781538693605

This article discusses the efficiency of the IEEE 802.11ac standard amendment from airtime resource usage point of view. An OFDM channel model is proposed as a function between its basic parameters and the application conditions. Analytical models are obtained for the data bits per OFDM symbol and the data frame transmission time as a function of the signal to noise ratio for the IEEE 802.11ac standard amendment. The model analysis shows that the error of the model is less than 6% for the most of the data frame size values. The proposed analytical models can be used to assess the effectiveness of the network and thus help in the design process of the networks.

关键词： Wireless local area network IEEE 802.11ac Signal to noise ratio Channel efficiency modulation and coding scheme Transmission time

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System Throughput and Immunity Analysis of a 802.11n WLAN in a Large Reverberation Chamber

System Throughput and Immunity Analysis of a 802.11n WLAN in...

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IEEE International Symposium on Electromagnetic Compatibility (ISEMC)

作者： Primiani, Valter Mariani Moglie, Franco Recanatini, Renzo Univ Politecn Marche DIBET Via Brecce Bianche 12 I-60131 Ancona Italy Univ Politecn Marche CSEMi I-60131 Ancona Italy

ISBN: (纸本)9781457708121

The paper presents some results concerning the use of a reverberation chamber (RC) to test a wireless local area network (WLAN) system based on 802.11n standard. The whole link (root and non-root bridge) operates inside the RC under different chamber loading conditions and varying the stirrer rotating speed. The effects of this multipath environment on system performances are checked measuring three transmission quality estimators: the ping average round trip time, the number of cyclic redundancy check (CRC) error, and the number of data retries. The behavior of these parameters is also analyzed changing the modulation and coding scheme (MCS) index using both one spatial stream and two spatial streams (MIMO). The same RC is used to carry out a radiated immunity test. The undesired signal is both a modulated and continuous wave injected into the active channel and into adjacent channels. The modulated wave is that prescribed by the IEC 61000-4-3 standard. Results reveal the high robustness of the 802.11n standard with respect to b and g standards when it operates in a hostile environment reproduced by an RC.

关键词： 802.11n WLAN 802.11n standard Bridges IEC 61000-4-3 standard IEC standards IEEE 802.11n Standard Indexes MIMO MIMO Optical switches Q factor Reverberation chamber adjacent channels cyclic redundancy check error encoding immunity analysis modulation and coding scheme reverberation chamber reverberation chambers spatial streams stirrer rotating speed telecommunication channels wireless LAN wireless local area network system

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Efficient MCS Selection Mechanisms for Multicasting over LTE Networks

Efficient MCS Selection Mechanisms for Multicasting over LTE...

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6th Joint IFIP Wireless and Mobile Networking Conference (WMNC)

作者： Bochrini, Stavroula Bouras, Christos Kokkinos, Vasileios Comp Technol Inst & Press Diophantus Patras Greece

ISBN: (纸本)9781467356169;9781467356152

In Long Term Evolution (LTE) networks, the Multimedia Broadcast/Multicast Services over Single Frequency Network (MBSFN) operation enables the delivery of the same multimedia content to a set or all the users in a cell, leading in this way to efficient utilization of the network resources. This is achieved through a time-synchronized common waveform that is transmitted from multiple cells for a given duration, which enables over-the-air combining, and therefore significantly improves the spectral efficiency. However, the performance of MBSFN is directly connected to the modulation and coding scheme (MCS) and the transmission mode that will be selected for the delivery of the multimedia data. This paper proposes three different approaches for the selection of the MCS during MBSFN transmissions. Main target is to determine the most efficient approach depending on the target that the operator may set, i.e. the approach that either maximizes the spectral efficiency or achieves a target spectral efficiency for various user distributions. The performance of the approaches is evaluated for scenarios that include users' mobility and for three different transmission modes in order to also examine the effectiveness of Multiple Input Multiple Output (MIMO) techniques.

关键词： Long term evolution multimedia broadcast and multicast single frequency network spectral efficiency modulation and coding scheme multiple input multiple output

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A-MSDU Frame Aggregation Mechanism Efficiency for IEEE 802.11ac Network. The Optimal Number of Frames in A-MSDU Block 18th

A-MSDU Frame Aggregation Mechanism Efficiency for IEEE 802.1...

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18th International Conference on Next Generation Teletraffic and Wired/Wireless Advanced Networks and Systems (NEW2AN) / 11th Conference on Internet of Things and Smart Spaces (ruSMART)

作者： Vikulov, Anton Paramonov, Alexander Bonch Bruevich State Univ Telecommun 22 Pr Bolshevikov St Petersburg Russia

ISBN: (纸本)9783030011680;9783030011673

This article discusses the effect of the A-MSDU frame aggregation mechanism on the efficiency of the IEEE 802.11 network. In order to define its main parameters as a function of the operation conditions the model of this mechanism is proposed. An analytical model is obtained for the probability of successful receipt of the code word as a function of bit error rate. An analytical model for the channel utilization efficiency as a function of bit error rate and number of frames in the A-MSDU block for the IEEE 802.11ac standard is also obtained. The proposed analytical models can be used to evaluate the network's performance. The method of determining the optimal number of frames in the A-MSDU block is proposed in terms of maximum efficiency of channel resource usage.

关键词： Wireless access network IEEE 802.11ac Frame aggregation A-MSDU Channel efficiency modulation and coding scheme Frame transmitting time

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Link Adaptation of MIMO- OFDM Systems Using Hidden Markov Model for High Speed Railway

Link Adaptation of MIMO- OFDM Systems Using Hidden Markov Mo...

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16th Asia-Pacific Conference on Communications (APCC)

作者： Lin, Kun-Yi Lin, Hsin-Piao Tseng, Ming-Chien Natl Taipei Univ Technol Inst Comp & Commun Engn Taipei Taiwan Ind Technol Res Inst Hsinchu Taiwan

ISBN: (纸本)9781424481293

A link adaptation scheme for MIMO-OFDM systems over high speed rail environment is addressed in this paper. In this study, a selection method of MIMO transmission mode and the modulation and coding scheme (MCS) according to the Rician channel K-factor from our previous work is considered. A hidden Markov model of time-varying Rician channel K-factor is constructed by using the real measured channel data on the high speed rail train. With the constructed hidden Markov model, the time correlation of Rician channel K-factor can be obtained and the time-varying K-factor value can be generated. By using the hidden Markov model, the K-factor value can be predicted to facilitate link adaptation since the K-factor may vary during feedback, especially in high mobility scenario. Simulation results show an average throughput improvement of 5Mbps.

关键词： Link adaptation hidden Markov model Rician channel K-factor high speed railway modulation and coding scheme

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