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54th IEEE Vehicular Technology Conference (VTC 2001)

作者： Sumanasena, MAK Evans, BG Univ Surrey Ctr Commun Syst Res Guildford GU2 7XH Surrey England

ISBN: (纸本)0780370058

An adaptive coding and modulation transmission scheme applicable for third-generation mobile-satellite systems is proposed in this paper. The transmitter dynamically selects the optimum coding and modulation scheme according to the environment in order to maximize the spectrum and power efficiency. A constant average Bit Error Rate (BER) is maintained without changing (or with a very small change to) the transmitted power, and hence the scheme eases the power control requirements. In addition, a higher throughput can be achieved compared to fixed (non adaptive) systems. Unlike other adaptive transmission systems, in our work the adaptation is based on the Rice factor. The paper also discusses a Rice factor estimation algorithm.

关键词： S-UMTS adaptive modulation and coding rice factor estimation

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adaptive modulation and coding based on Reinforcement Learning for 5G Networks

Adaptive Modulation and Coding based on Reinforcement Learni...

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IEEE Global Communications Conference (IEEE GLOBECOM)

作者： Mota, Mateus P. Araujo, Daniel C. Costa Neto, Francisco Hugo de Almeida, Andrd L. E. Cavalcanti, E. Rodrigo P. Univ Fed Ceara GTEL Wireless Telecommun Res Grp Fortaleza Ceara Brazil

ISBN: (纸本)9781728109602

We design a self-exploratory reinforcement learning (RL) framework, based on the Q-learning algorithm, that enables the base station (BS) to choose a suitable modulation and coding scheme (MCS) that maximizes the spectral efficiency while maintaining a low block error rate (BLER). In this framework, the BS chooses the MCS based on the channel quality indicator (CQI) reported by the user equipment (UE). A transmission is made with the chosen MCS and the results of this transmission arc converted by the BS into rewards that the BS uses to learn the suitable mapping from CQI to MCS. Comparing with a conventional fixed look-up table and the outer loop link adaptation, the proposed framework achieves superior performance in terms of spectral efficiency and BLER.

关键词： Reinforcement Learning adaptive modulation and coding Link Adaptation Machine Learning Q-Learning

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adaptive modulation and coding for BIC-UFMC and BIC-OFDM systems taking CFO into account.

Adaptive modulation and coding for BIC-UFMC and BIC-OFDM sys...

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23rd IEEE Symposium on Communications and Vehicular Technology in the Benelux (SCVT)

作者： Debels, E. Del Fiorentino, P. Vitiello, C. Van Hecke, J. Giannetti, F. Luise, M. Lottici, V. Moeneclaey, M. Univ Ghent TELIN Dept St Pietersnieuwstr 41 B-9000 Ghent Belgium Univ Pisa Dept Informat Engn I-56122 Pisa Italy

ISBN: (纸本)9781509043613

The performance of multicarrier systems can be considerably degraded because of inter-carrier interference (ICI) caused by a carrier frequency offset (CFO) between the transmitter and the receiver. A recently developed multicarrier modulation technique, referred to as uniform filtered multicarrier (UFMC), improves the robustness against CFO, thereby relaxing the synchronization requirements, consequently providing energy efficient and low latency transmissions. However, the goodput (GP) of the system still rapidly drops with increasing CFO when using the classical adaptive modulation and coding (AMC) schemes based on the SNRs of the subcarriers, because they ignore the presence of the CFO-induced ICI. To tackle this problem, this contribution performs the AMC, also taking into account the ICI caused by the CFO, and thereby achieving a significant increase of the GP.

关键词： UFMC BIC adaptive modulation and coding Goodput CFO

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adaptive modulation and coding (AMC) in Cooperative Communication Channels

Adaptive Modulation and Coding (AMC) in Cooperative Communic...

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22nd IEEE Signal Processing and Communications Applications Conference (SIU)

作者： Sunu, Cansu Aktas, Emre Hacettepe Univ Elekt & Elekt Muhendisligi Bolumu Ankara Turkey

ISBN: (纸本)9781479948741

In this paper, we construct an adaptive modulation and coding (AMC) protocol for a wireless communication system model that contains a transmitter, receiver and relay. The constructed AMC model is simulated and compared with non-cooperative AMC model. In cooperative AMC model, a willing to cooperate relay listens the ongoing transmission between transmitter and receive, and helps transmitter if it is necessary. Channel is assumed as slow changing Nakagami-m fading. Channel is modelled as Markov chain and each AMC mode is assigned to a Markov state. The effect of target packet error rate (PER) is investigated. Simulation results shows that constructed cooperative AMC model provides performance gain.

关键词： wireless communications cooperative communication adaptive modulation and coding Nakagami-m fading channel

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adaptive modulation and coding for Broadcast DVB-H Systems

Adaptive Modulation and Coding for Broadcast DVB-H Systems

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20th IEEE Symposium on Personal, Indoor and Mobile Radio Communications

作者： El Shabrawy, Tallal Osama Wahed, Sherif Hassan Abdel Germany Univ Cairo Egypt

ISBN: (纸本)9781424451234

Broadcasting live digital TV to a small battery-powered handheld device is very challenging. One of the evolving technologies to provide such services is DVB-H (Digital Video Broadcasting over Handheld). Wireless channels constitute a fast varying environment that is hostile to reliable communications. adaptive modulation and coding (AMC) is one of the most promising mechanisms to cope with the dynamic fading of wireless channels. However, the broadcast nature of DVB-H systems restricts the use of AMC as the transmitter must adapt to the user experiencing the worst channel. This would constitute a penalty to other users experiencing good channels. In this paper, a novel framework for AMC is proposed for broadcast DVB-H systems. The transmitted frames are arranged such that higher modulation symbols are transmitted followed by lower modulation symbols. Each group of symbols having the same modulation technique are arranged such that higher code rates (i.e. weaker codes) are transmitted first and then incremental symbols (constituting stronger codes) are transmitted afterwards. The proposed framework is then deployed as a power saving mechanism since power consumption has always been a crucial challenge for handheld devices. The proposed adaptive receiver adjusts its modulation and coding configuration to receive and detect the minimal amount of bits that guarantee a target Bit Error Rate (BER) performance. This is shown to result in significant potential for saving of reception and processing powers (up to 71.875%). Numerical analysis for the power saving potential and BER performance of the proposed scheme is performed for flat Rayleigh fading channel. Simulation results for the operation of DVB-H under the proposed scheme in a Typical Urban 6-paths (TU6) channel are presented. Finally, the effect of adaptation rate (i.e. how often the modulation and coding are allowed to change) on power saving potential is investigated.

关键词： Broadcast DVB-H adaptive modulation and coding AMC power consumption power saving

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Joint Relay Selection and adaptive modulation and coding for Wireless Cooperative Communications

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IEEE SENSORS JOURNAL 2021年第22期21卷 25508-25516页

作者： Xiao, Yong Jin, Xin Shen, Yanhua Guan, Quansheng China Southern Power Grid Elect Power Res Inst Guangzhou Peoples R China South China Univ Technol SCUT Sch Mat Sci & Engn Guangzhou 510640 Peoples R China South China Univ Technol Sch Informat & Elect Engn Guangzhou 510640 Peoples R China

This paper considers a wireless cooperative communication system with the adaptive modulation and coding (AMC). We take the joint relay and AMC mode selection as two time-scales of optimization problems, which aim at maximizing the achievable data rate. We treat the best relay selection as a long-term objective and the best AMC mode selection as a short-term objective, to limit the signaling overhead for the wireless communication system. However, the evaluation of the achievable data rate for any of relay and AMC mode combinations needs the estimation of the wireless channel. To this end, we propose an online optimization-while-estimation algorithm based on discrete stochastic approximation to jointly solve both the relay and AMC selection problems. The algorithm requires only per-frame channel sampling and estimation in each algorithm iteration, and approaches the optimal achievable data rate asymptotically. Simulation results show that our proposed algorithm can quickly converge to the maximum achievable data rate.

关键词： Relays Wireless communication Wireless sensor networks Signal to noise ratio Cooperative communication modulation Encoding Wireless cooperative communications relay selection adaptive modulation and coding stochastic approximation

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Constellation and Rate Selection in adaptive modulation and coding Based on Finite Blocklength Analysis and Its Application to LTE

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2014年第10期13卷 5496-5508页

作者： Meng, Jin Yang, En-Hui Univ Waterloo Dept Elect & Comp Engn Waterloo ON N2L 3G1 Canada

This paper tackles the constellation and channel coding rate selection problem in adaptive modulation and coding (AMC) for MIMO systems. Based on information theoretical results in finite blocklength analysis of channel capacity, a new selecting rule is proposed for narrow-band MIMO systems, and further extended to wide-band MIMO OFDM systems over channels subject to frequency-selective fading. When applied to Long Term Evolution (LTE) systems, the proposed selecting rule yields better performance in comparison with existing rules in the literature.

关键词： Finite blocklength analysis of channel capacity Taylor expansion adaptive modulation and coding throughput MIMO space time coding OFDM flat and frequency-selective fading LTE

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Downlink scheduling schemes for CDMA networks with adaptive modulation and coding and multicodes

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2007年第10期6卷 3668-3677页

作者： Kwan, Raymond Leung, Cyril Simon Fraser Univ Sch Engn Sci Burnaby BC V5A 1S6 Canada Univ British Columbia Dept Elect & Comp Engn Vancouver BC V6T 1Z4 Canada

For the problem of allocating radio resources in the downlink of a CDMA network studied in [1], the modulation and coding schemes, numbers of multicodes, and transmit powers used for all mobile stations (MS's) are jointly chosen so as to maximize the total transmission bit rate during each scheduling interval, subject to certain constraints. The approach employs discrete mathematical programming, which is potentially complex, and analytical solutions are not available. In this paper, sub-optimal approaches are examined. In particular, analytical expressions are derived for optimal resource allocation involving a single MS. Based on the single-MS solution, a sub-optimal, sequential optimization procedure for multiple MS's is presented. Numerical results show that when the order for allocating resources to MS's is judiciously chosen based on the MS channel conditions and/or traffic loads, the sequential solution is an attractive alternative to the more complex joint optimization. This is especially true when radio resources are scarce.

关键词： adaptive modulation and coding CDMA downlink scheduling high-speed packet data multicode

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Performance analysis of wireless multi-user VoIP system with adaptive modulation and coding

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WIRELESS NETWORKS 2014年第4期20卷 747-757页

作者： Lee, Howon Lee, Soobin Cho, Dong-Ho Hankyong Natl Univ Anseong Gyeonggi South Korea Korea Adv Inst Sci & Technol Taejon 305701 South Korea Korea Adv Inst Sci & Technol Dept Elect Engn Taejon 305701 South Korea

In this paper, we propose a new framework to analyze performance considering finite-length queuing and adaptive modulation and coding for multi-user Voice over IP (VoIP) services in wireless communication systems. We formulate an uplink VoIP system as a two-dimensional discrete-time Markov chain (DTMC) based on a Markov modulated Poisson process traffic model for VoIP services and modulation and coding scheme (MCS)-level set transition reflecting users' channel variations. We extend the transition modeling of the MCS-level for a single-user to the transition modeling of the MCS-level set for multiple users. Since the users can have various MCS combinations in the case of a multi-user system, the MCS-level set transitions are more complicated than the MCS-level transitions of the single-user case. Throughout our DTMC formulation, we present various performance metrics, such as average queue-length, average throughput, packet dropping probability, packet loss probability, and so on. By using the results of the packet loss probability, we can find an optimum packet error rate value that minimizes the total packet loss probability.

关键词： Uplink VoIP service Markov modulated Poisson process Discrete-time Markov chain adaptive modulation and coding Radio resource allocation

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Threshold controlling scheme for adaptive modulation and coding system

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IEICE TRANSACTIONS ON COMMUNICATIONS 2006年第5期E89B卷 1598-1604页

作者： Takeda, Daisuke Chow, Yuk C. Strauch, Paul Tsurumi, Hiroshi Toshiba R&D Ctr Kawasaki Kanagawa 2128582 Japan

adaptive modulation and coding scheme (AMC) is an effective way to achieve high data rate communication. In AMC system, the key issue is to determine the rule for switching among different modulation and coding Schemes (MCSs). In this paper, adaptive threshold controlling scheme for AMC is proposed. The proposed scheme controls switching thresholds according to target block error rate. Simulation results have shown that the throughput performance of the proposed scheme is very close to the performance, which obtained by the optimum SIR thresholds. We also proposed downlink transmission power control (TPC) scheme suitable for AMC. The throughput of the lowest MCS is improved and the tramnission power of the highest MCS can be reduced with the proposed algorithm.

关键词： adaptive modulation and coding SIR CRC transmission power control

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