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European Conference on Networks and Communications (EuCNC)

作者： Bouras, Christos Kanakis, Nikolaos Kokkinos, Vasileios Papachristos, Nikolaos Vouyioukas, Demosthenes Comp Technol Inst & Press Diophantus Patras Greece Univ Patras Comp Engn & Informat Dept GR-26110 Patras Greece Univ Aegean Dept Informat & Commun Syst Engn Mitilini Greece

ISBN: (纸本)9781509028931

Femtocells enhance indoor coverage of mobile services using the owner's broadband connection. They were initially designed to serve a number of subscribed User Equipments within their range. This design however, resulted in underutilization of the femtocells resources, and simultaneously in high interference levels for nearby non-subscribed users. Nowadays, femtocells can support multicast transmissions, while their hybrid operation allows non-subscribed users to use a portion of their resources. In this paper we propose a novel mechanism that is based on the selection of the appropriate modulation and coding scheme. The mechanism allows nonsubscribed users to utilize a portion of the femtocells' resources for multicast transmissions when located inside their coverage, without affecting the owners' satisfaction. The simulation results show that depending on the portion of the femtocells' resources allocated to non- subscribed users, the mechanism may significantly increase the average user throughput.

关键词： modulation and coding scheme mbsfn femtocells hybrid access next generation mobile networks

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Leveraging Deep-Learning for Adaptive coding and modulation for LEO Satellite-Terrestrial Networks

Leveraging Deep-Learning for Adaptive Coding and Modulation ...

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IEEE/CIC International Conference on Communications in China (ICCC)

作者： Xia, Yuhan Zhang, Xin Qin, Xiaohan Zhang, Zitian Zhang, Yu Ma, Ting Zhou, Haibo Nanjing Univ Sch Elect Sci & Engn Nanjing Peoples R China Zhejiang Gongshang Univ Sch Informat & Elect Engn Hangzhou 310018 Peoples R China Topxgun Robot Co Ltd Nanjing Peoples R China Nanjing Univ Sci & Technol Sch Elect & Opt Engn Nanjing Peoples R China

ISBN: (纸本)9798350378412

Low-earth-orbit (LEO) satellite-terrestrial network (LSTN) is expected to play a significant role in the next-generation wireless networks (6G), providing global coverage and facilitating various 6G applications. However, the high dynamics of channel state information (CSI) in LSTN have posed challenges to modulation and coding schemes (MCS), which adversely affects the correctness of data transmission and the quality of service (QoS) expected by users. To enhance the communication reliability of LSTN, in this paper, we investigate the adaptive coding and modulation (ACM) method under the digital video broadcasting (DVB) standards. We first establish a channel model and then introduce an ACM method involving channel state estimation, channel state prediction, and MCS switching. Subsequently, the least squares (LS) algorithm is leveraged for channel estimation and we propose an ARIMA-Bidirectional Long Short-Term Memory (AB-LSTM) algorithm specifically for forecasting time-series signal-to-noise ratio (SNR) values for precise channel prediction. Then MCS switching is conducted based on the predicted SNR and switching threshold based on DVB standards. We conduct extensive simulations to show that our proposed algorithms can achieve higher estimation and prediction accuracy, and the introduced ACM method can effectively optimize the usage of channel capacity.

关键词： LEO satellite-terrestrial network adaptive coding and modulation DVB modulation and coding scheme

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Proposal of CQI Table Switching Control Method Corresponding to 256-QAM for CRE in HetNet 32

Proposal of CQI Table Switching Control Method Corresponding...

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32nd International Conference on Information Networking (ICOIN)

作者： Naganuma, Norihiro Osawa, Kai Mashino, Jun Suyama, Satoshi Otsuka, Hiroyuki Kogakuin Univ Grad Sch Engn Tokyo 1638677 Japan NTT DOCOMO INC Res Labs Yokosuka Kanagawa 2398536 Japan

ISBN: (纸本)9781538622902

Higher-order modulation such as 256-QAM is a key technology to increase data rates within a limited bandwidth. This paper proposes a channel quality indicator (CQI) table switching control method corresponding to 256-QAM that improves the 5-percentile user throughput in Heterogeneous networks (HetNets), in which user equipments (UEs) connected to pico cell can use different CQI table depending on where UE is located within the original pico cell or the related CRE region. The features of the proposed CQI table switching control method are described in comparison with the conventional method. Computer simulation results such as average, 5-percentile and 95-percentile user throughput are provided as parameters of cell selection offset for two types of HetNets, i.e., co-channel deployment with time-domain enhanced inter-cell interference coordination (eICIC), and different frequency deployment between macro and pico cells. We confirmed that the proposed method can improve 5-percentile user throughput while maintain or improve the average and the 95-percentile user throughput for the co-channel HetNet with eICIC.

关键词： 256-QAM CQI table modulation and coding scheme HetNet CRE

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An Efficient Resource Sharing and Multicast Scheduling for Video over Wireless Networks

An Efficient Resource Sharing and Multicast Scheduling for V...

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IEEE International Conference on Emerging Trends in Computing, Communication and Nanotechnology (ICECCN)

作者： Kalaiselvi, P. Mahendran, N. M Kumarasamy Coll Engn Dept ECE Karur India

ISBN: (纸本)9781467350372;9781467350365;9781467350358

Multicasting video over wireless networks is a best effort service. To multicast a video, Scalable Video coding with spatial, temporal and quality scalabilities is adopted. Scalable Video multicast system consists of channel probing stage and transmission stage. The optimal resource allocation problem is formulated by maximizing the video quality of the clients subject to transmission energy and channel access constraints. This problem is a joint optimization of the selection of modulation and coding scheme (MCS), and the transmission power allocation. The proposed scheme is of linear complexity and leads to the maximized video quality for the admitted clients. It also satisfies the energy budget and access time constraints.

关键词： Energy efficient transmission modulation and coding scheme resource allocation scalable video coding

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Impact of Feedback Delays on EESM-based Wideband Link Adaptation: Modeling and Analysis

Impact of Feedback Delays on EESM-based Wideband Link Adapta...

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IEEE Global Communications Conference (GLOBECOM)

作者： Francis, Jobin Mehta, Neelesh B. Indian Inst Sci IISc Dept Elect Commun Engn Bangalore Karnataka India

ISBN: (纸本)9781479935123

In orthogonal frequency division multiplexing (OFDM) systems, such as long term evolution (LTE) and WiMAX, a codeword is transmitted over a group of subcarriers. Since the subcarriers see different channel gains in a frequency-selective channel, the modulation and coding scheme (MCS) of the codeword must be selected based on the vector of signal-to-noise-ratios (SNRs) of these subcarriers. Exponential effective SNR mapping (EESM) simplifies this problem by mapping the vector of SNRs into a single, equivalent flat-fading SNR. We develop a new analytical framework to characterize the throughput of EESM-based rate adaptation in such wideband channels in the presence of feedback delays, which make the choice of the MCS partially outdated by the time data transmission takes place. To this end, we first propose a novel bivariate gamma distribution to model the joint statistics of EESM at the times of estimation and data transmission. We then derive a novel expression for the throughput as a function of feedback delay. Our framework works for both correlated and independent subcarriers and for various multiple antenna diversity modes, and is accurate over a wide range of delays.

关键词： Long Term Evolution OFDM modulation WiMax broadband networks codes feedback gamma distribution wireless channels EESM-based wideband link adaptation LTE MCS OFDM system WiMAX bivariate gamma distribution channel gain codeword data transmission exponential effective SNR mapping feedback delay frequency-selective channel joint statistics long term evolution modulation and coding scheme multiple antenna diversity mode orthogonal frequency division multiplexing signal-to-noise-ratio subcarrier group wideband channel Adaptation models Delays Joints OFDM Signal to noise ratio Throughput Wireless communication

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An Intelligent Optimization Algorithm for Joint MCS and Resource Block Allocation in LTE Femtocell Downlink with QoS Guarantees 5

An Intelligent Optimization Algorithm for Joint MCS and Reso...

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5th International Conference on Game Theory for Networks

作者： Li, Longfei Chen, Xin Xiang, Xudong Beijing Informat Sci & Technol Univ Beijing Key Lab Internet Culture & Digital Dissem Comp Sch Beijing 100101 Peoples R China Beijing Informat Sci & Technol Univ Comp Sch Beijing 100101 Peoples R China Univ Sci & Technol Beijing Dept Comp Sci & Technol Beijing 100083 Peoples R China

ISBN: (纸本)9780990994305

In this paper, we address the problem of joint Resource Block (RB) allocation and modulation-and-coding scheme (MCS) selection for LTE femtocell DownLink (DL). We first formulate the problem as an Integer Linear Program (ILP) whose objective is to minimize the number of allocated RBs of a closed femtocell, while guaranteeing minimum throughput for each user. In view of the NP-hardness of the ILP, we then propose an intelligent optimization algorithm called ACO-HM algorithm with reduced polynomial time complexity. In the ACO-HM algorithm, the Ant Colony Optimization (ACO) algorithm is to allocate appropriate RBs to mobile users, while the Harmonic Mean (HM) method is to select a better MCS than the MINimum/MAXimum MCS selection schemes (MIN/MAX). Simulation results show that compared with the ACO-MIN algorithm and the ACO-MAX algorithm, the proposed ACO-HM algorithm achieves better performance with fewer RBs and provides Quality-of-Service (QoS) guarantees.

关键词： Femtocell modulation and coding scheme resource block QoS guarantees

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Model-Based Adaptive modulation and coding with Latent Thompson Sampling 32

Model-Based Adaptive Modulation and Coding with Latent Thomp...

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32nd IEEE Annual International Symposium on Personal, Indoor and Mobile Radio Communications (IEEE PIMRC)

作者： Saxena, Vidit Tullberg, Hugo Jalden, Joakim KTH Royal Inst Technol Stockholm Sweden Ericsson Res Stockholm Sweden

ISBN: (纸本)9781728175867

Wireless links use adaptive modulation and coding (AMC) to optimize data transmission over a dynamic channel. Traditional AMC schemes rely on simple heuristics to track the instantaneous channel state. While attractive for their low implementation and operational complexity, these schemes are known to be suboptimal in a large range of operating environments. Further, several such schemes require careful parameter tuning, which can be both expensive and error-prone. In this paper, we propose latent Thompson sampling (LTS) for AMC, which efficiently tracks the wireless channel by modeling a latent, low-dimensional, channel state. LTS features both a low computational complexity and fast learning dynamics, and requires minimal tuning effort. We evaluate LTS in stationary as well as fading wireless channels, where LTS improves the link throughput by up to 100% compared to state-of-the-art schemes.

关键词： Link Adaptation modulation and coding scheme Multi-armed bandits Reinforcement Learning Cellular Networks Rate Sampling

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Methodology for mode selection in MIMO-OFDM system

Methodology for mode selection in MIMO-OFDM system

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IEEE Wireless Communications and Networking Conference

作者： Chan, Peter W. C. Pan, Z. G. Zhao, Xueyuan Lo, C. M. Zhang, Kai Lee, Derek C. K.

ISBN: (纸本)9781424419968

Mode selection problem in MIMO-OFDM system is addressed. A general formulation is introduced to decompose the problem into two decoupled sub-problems: modulation and coding scheme (MCS) selection, and space-time processing (STP) optimization, each of which can be tackled more systematically. Mode selection algorithms can then be developed using a channel quality indicator (CQI) metric. The methodology is illustrated using the platform of IEEE802.11n. The qualities of multiple CQI metrics are compared in terms of "coherency" and their performances are evaluated in terms of system goodput. This has been shown that the metric we proposed outperforms the other metrics.

关键词： mode selection WLAN MCS selection modulation and coding scheme MIMO OFDM IEEE802.11n

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Investigation of Degradation Factors for Adaptive modulation and coding in OFDM-MIMO Multiplexing 79

Investigation of Degradation Factors for Adaptive Modulation...

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IEEE 79th Vehicular Technology Conference (VTC-Spring)

作者： Han, Bing Kawamura, Teruo Kakishima, Yuichi Sawahashi, Mamoru Tokyo City Univ Tokyo Japan NTT DOCOMO INC Sagamihara Kanagawa Japan

ISBN: (纸本)9781479944828

This paper investigates the throughput performance using adaptive modulation and coding (AMC) focusing on the causes of impairment to Orthogonal Frequency Division Multiplexing (OFDM) - Multiple-Input Multiple-Output (MIMO) multiplexing. We first investigate the influence of a limited number of modulation and coding schemes (MCSs) and channel estimation error for MCS selection based on mutual information (MI). Second, we clarify the effect of MCS selection error on an increasing maximum Doppler frequency due to the round trip delay time (RTT) in comparison to the throughput upper bound that is computed from the MCS combination providing the maximum throughput considering the block error. Third, we clarify the effect of channel estimation error of maximum likelihood detection (MLD) when using reference signal (RS) based channel estimation in comparison to ideal channel estimation. Through the evaluations, we clarify the impairment factors that degrade the achievable throughput for OFDM-MIMO multiplexing using AMC in an actual multipath fading channel.

关键词： OFDM MIMO multiplexing AMC modulation and coding scheme round trip delay time

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Lightweight LSTM-Based Adaptive CQI Feedback scheme for IoT Devices

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SENSORS 2023年第10期23卷 4929-4929页

作者： Han, Noel Kim, Il-Min So, Jaewoo Sogang Univ Dept Elect Engn Seoul 04107 South Korea Queens Univ Dept Elect & Comp Engn Kingston ON K7L 3N6 Canada

As the number of Internet of things (IoT) devices increases exponentially, scheduling and managing the radio resources for IoT devices has become more important. To efficiently allocate radio resources, the base station (BS) needs the channel state information (CSI) of devices every time. Hence, each device needs to periodically (or aperiodically) report its channel quality indicator (CQI) to the BS. The BS determines the modulation and coding scheme (MCS) based on the CQI reported by the IoT device. However, the more a device reports its CQI, the more the feedback overhead increases. In this paper, we propose a long short-term memory (LSTM)-based CQI feedback scheme, where the IoT device aperiodically reports its CQI relying on an LSTM-based channel prediction. Additionally, because the memory capacity of IoT devices is generally small, the complexity of the machine learning model must be reduced. Hence, we propose a lightweight LSTM model to reduce the complexity. The simulation results show that the proposed lightweight LSTM-based CSI scheme dramatically reduces the feedback overhead compared with that of the existing periodic feedback scheme. Moreover, the proposed lightweight LSTM model significantly reduces the complexity without sacrificing performance.

关键词： channel quality indicator feedback long short-term memory lightweight model modulation and coding scheme feedback overhead

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