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Reinforcement Learning for Efficient and Tuning-Free Link Adaptation

IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2022年第2期21卷 768-780页

作者： Saxena, Vidit Tullberg, Hugo Jalden, Joakim KTH Royal Inst Technol Div Informat Sci & Engn S-11428 Stockholm Sweden Ericsson Res S-16480 Stockholm Sweden

Wireless links adapt the data transmission parameters to the dynamic channel state - this is called link adaptation. Classical link adaptation relies on tuning parameters that are challenging to configure for optimal link performance. Recently, reinforcement learning has been proposed to automate link adaptation, where the transmission parameters are modeled as discrete arms of a multi-armed bandit. In this context, we propose a latent learning model for link adaptation that exploits the correlation between data transmission parameters. Further, motivated by the recent success of Thompson sampling for multi-armed bandit problems, we propose a latent Thompson sampling (LTS) algorithm that quickly learns the optimal parameters for a given channel state. We extend LTS to fading wireless channels through a tuning-free mechanism that automatically tracks the channel dynamics. In numerical evaluations with fading wireless channels, LTS improves the link throughout by up to 100% compared to the state-of-the-art link adaptation algorithms.

关键词： Wireless communication Interference Signal to noise ratio Reinforcement learning Fading channels Throughput Channel estimation Wireless networks adaptive modulation and coding reinforcement learning thompson sampling outer loop link adaptation

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A 10-state model for an AMC scheme with repetition coding in mobile wireless networks

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EURASIP JOURNAL ON WIRELESS COMMUNICATIONS AND NETWORKING 2013年第1期2013卷 1-15页

作者： Nguyen Quoc-Tuan Dinh-Thong Nguyen Lam Sinh Cong Vietnam Natl Univ Hanoi Vietnam Univ Technol Sydney Sydney NSW 2007 Australia

In modern broadband wireless access systems such as mobile worldwide interoperability for microwave access (WiMAX) and others, repetition coding is recommended for the lowest modulation level, in addition to the mandatory concatenated Reed-Solomon and convolutional code data coding, to protect vital control information from deep fades. This paper considers repetition coding as a time-diversity technique using maximum ratio combining (MRC) and proposes techniques to define and to calculate the repetition coding gain G (r) and its effect on bit error rate (BER) under the two fading conditions: correlated lognormal shadowing and composite Rayleigh-lognormal fading also known as Suzuki fading. A variable-rate, variable-power 10-state finite-state Markov channel (FSMC) model is proposed for the implementation of the adaptive modulation and coding (AMC) scheme in mobile WiMAX to maximize its spectral efficiency under constant power constraints in the two fading mechanisms. Apart from the proposed FSMC model, the paper also presents two other significant contributions: one is an innovative technique for accurate matching of moment generating functions, necessary for the estimation of the probability density function of the combiner's output signal-to-noise ratio, and the other is efficient and fast expressions using Gauss-Hermite quadrature approximation for the calculation of BER of QPSK signal using MRC diversity reception.

关键词： Lognormal fading Suzuki fading Gauss-Hermite polynomial Moment generating function WiMAX adaptive modulation and coding Repetition coding Finite-state Markov channel model

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Cross-layer optimization for video summary transmission over wireless networks

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IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 2007年第4期25卷 841-850页

作者： Wu, Dalei Ci, Song Wang, Haohong Univ Nebraska Dept Comp & Elect Engn Omaha NE 68182 USA Marvell Semicond Santa Clara CA 95054 USA

Video summarization has gained increased popularity in the emerging multimedia communication applications, however, very limited work has been conducted to address the transmission problem of video summary frames. In this paper, we propose a cross-layer optimization framework for delivering video summaries over wireless networks. Within a rate-distortion theoretical framework, the source coding, allowable retransmission, and adaptive modulation and coding have been jointly optimized, which reflects the joint selection of parameters at physical, data link and application layers. The goal is to achieve the best video quality and content coverage of the received summary frames and to meet the delay constraint. The problem is solved using Lagrangian relaxation and dynamic programming. Experimental results indicate the effectiveness and efficiency of the proposed optimization framework, especially when the delay budget imposed by the upper layer applications is small, where more than 10% distortion gain can be achieved.

关键词： universal multimedia access video summarization adaptive modulation and coding automatic repeat request cross-layer optimization rate distortion video communication

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Radio-aware resource allocation architecture for QoS differentiation in WiMAX networks

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WIRELESS NETWORKS 2015年第8期21卷 2711-2726页

作者： Pizzi, Sara Molinaro, Antonella Araniti, Giuseppe Univ Mediterranea Reggio Calabria Reggio Di Calabria Italy

One of the keys to the success of WiMAX is its capability of supporting traffic with heterogeneous quality of service (QoS) requirements. The current standard specifies the general QoS architecture for WiMAX but the design of the main building blocks (e.g., connection admission control, packet schedulers) is left up to the vendors' implementation. This gap motivates the paper that aims to design and analyse a channel-aware QoS framework for efficiently managing radio resources in a WiMAX network. The proposed architecture integrates the specifications of (1) a connection admission control module and a packet scheduler implemented at the base station (BS) to manage bandwidth requests from the subscriber stations (SSs), and (2) a scheduler at the SS that distributes the granted resources among the active data flows. Simulation results show that the proposed framework enables QoS differentiation and intra-class fairness, and demonstrate that a combined design of the BS and SS schedulers is necessary for effective QoS provisioning.

关键词： WiMAX Quality of service Scheduling Channel awareness adaptive modulation and coding

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adaptive radio resource management for maximizing reward and balancing loads in 4G hybrid universal mobile telecommunications system and long term evolution communications

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WIRELESS COMMUNICATIONS & MOBILE COMPUTING 2015年第3期15卷 510-526页

作者： Chang, Ben-Jye Liang, Ying-Hsin Cao, Kai-Xiang Natl Yunlin Univ Sci & Technol Dept CSIE Touliu Taiwan Nan Kai Univ Technol Dept MAA Caotun Taiwan

The universal mobile telecommunications system (UMTS) and long term evolution (LTE)/LTE-advanced specifications have been proposed to offer high data rate for the forwarding link under high-mobility wireless communications. The keys include supporting multi-modes of various coding schemes (e.g., VSF-OFCDM, OFDM, OFDMA), multiple-input multiple-output, relay networks, and so on. To balance loads among different communication interfaces is one of the most important issues that should be addressed for achieving efficient radio resource allocations. In a shared packet service, the 3GPP UMTS adopts the VSF-OFCDM interface to allocate orthogonal codes of an OVSF code tree in two-dimension (2D) spreading at the time and frequency domains. However, it easily leads to high packet loss rate and high bandwidth waste rate, because it does not consider interference and the adaptive modulation and coding scheme simultaneously. Conversely, although the LTE/LTE-advanced interface offers a high data rate, it suffers from unbalanced loads and moderate reward. This paper thus proposes an adaptive radio resource allocation for balancing loads between the UMTS and LTE/LTE-advanced interfaces according to various interference and mobility environments. In addition, an adaptive multi-code allocation is proposed for the UMTS to minimize the bandwidth waste rate while guaranteeing quality of service. Numerical results indicate that the proposed approach outperforms other approaches in fractional reward loss and system utilization. Copyright (c) 2013 John Wiley & Sons, Ltd.

关键词： adaptive radio resource management adaptive modulation and coding load balancing resource block 2D-spreading multiple input multiple output multicode LTE-A

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Iterative Learning for Reliable Link Adaptation in the Internet of Underwater Things

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IEEE ACCESS 2021年 9卷 30408-30416页

作者： Byun, Junghun Cho, Yong-Ho Im, Taeho Ko, Hak-Lim Shin, Kyungseop Kim, Juyeop Jo, Ohyun Chungbuk Natl Univ Dept Comp Sci Cheongju 28644 South Korea Mokpo Natl Univ Dept Elect Informat & Commun Engn Mokpo 58554 South Korea Hoseo Univ Dept Informat & Commun Engn Asan 31499 South Korea Sangmyung Univ Dept Comp Sci Seoul 03016 South Korea Sookmyung Womens Univ Dept Elect Engn Seoul 04310 South Korea

Given the ever-increasing interest in the Internet of Underwater Things (IoUT), various studies are ongoing to solve some of the practical problems affecting the development of underwater wireless communication. The main problems are related to the use of acoustic waves in a water medium, in which extremely high propagation loss and drastic channel fluctuation are common. On the basis of hands-on experience and measurements made in real underwater environments, the conventional adaptive modulation and coding (AMC), which uses the high correlation between SNR (Signal to Noise Ratio) and BER (Bit Error Rate), might not be affordable in underwater environments because the normal correlation between SNR and BER almost disappears altogether. This work therefore collectively takes into account multiple quality factors of communication at the same time by creating, analysing and validating the machine learning model to predict the most adequate communication parameters to solve the problem. The dataset of underwater wireless communication used in the learning models was obtained from measurements made in a real underwater environment near the Gulf of Incheon, South Korea, using a practical testbed designed and implemented by the authors. The estimated network throughput based on the communications parameters predicted using the machine learning models was enhanced by up to 25% compared with the conventional handcraft method.

关键词： Machine learning Correlation Signal to noise ratio Predictive models Wireless communication Sea measurements Binary phase shift keying Link adaptation adaptive modulation and coding underwater wireless communications machine learning Internet of Underwater Things

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adaptive Transmission in Cellular Networks: Fixed-Rate Codes With Power Control Versus Physical Layer Rateless Codes

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2019年第6期18卷 3005-3018页

作者： Rajanna, Amogh Dettmann, Carl P. Univ Bristol Sch Math Bristol BS8 1TH Avon England

adaptive transmission schemes are a crucial aspect of radio design for future wireless networks. This paper studies the performance of two classes of adaptive transmission schemes in cellular downlink. One class is based on physical layer rateless codes with constant transmit power and the other uses fixed-rate codes in conjunction with power adaptation. Using a simple stochastic geometry model for the cellular downlink, the focus is to compare the adaptivity of fixed-rate codes with power adaptation to that of physical layer rateless codes only. The performance of both the rateless and fixed-rate coded adaptive transmission schemes are compared by evaluating the typical user success probability and rate achievable with the two schemes. Based on both the theoretical analysis and simulation results, it is clearly shown that the fixed-rate codes require power control to maintain good performance, whereas the physical layer rateless codes with constant power can still provide robust performance.

关键词： adaptive modulation and coding rateless codes transmit power adaptation fixed-rate codes adaptive transmission cellular downlink and fractional power control

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adaptive Resource Allocation for Scalable Video Transmission over OFDMA Systems

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WIRELESS PERSONAL COMMUNICATIONS 2016年第1期91卷 79-99页

作者： Yang, Zan Zhao, Yuping Minist Transport Transport Planning & Res Inst Beijing 100028 Peoples R China Peking Univ Sch Elect Engn & Comp Sci State Key Lab Adv Opt Commun Syst & Networks Beijing 100871 Peoples R China

We propose an adaptive resource allocation algorithm for scalable H.264 video transmission over orthogonal frequency-division multiple-access (OFDMA) systems. The algorithm explores the scalability of the video codec and the multiuser diversity of OFDMA systems to achieve enhanced efficiency and video quality. We use the peak signal-to-noise ratio (PSNR) as the measure metric of video quality, and jointly optimize the video layer extraction and radio resource allocation, considering the heterogeneity of video sources and channel conditions. Given the fact that different quality layers of the video have different importance, an adaptive modulation and coding scheme is proposed where a fixed coding rate is used for each quality layer, and unequal error protection is implemented for different layers. We also propose a subcarrier allocation algorithm to assign subcarriers for different layers of different users' videos to maximize the average PSNR of users while satisfying the base layer requirement. The proposed resource allocation algorithm has a low complexity and is suitable for practical implementations. We further develop an end-to-end simulation testbed to demonstrate the effectiveness of the proposed transmission scheme.

关键词： Scalable video H.264 OFDMA adaptive modulation and coding Subcarrier allocation

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Classification of Error Correcting Codes and Estimation of Interleaver Parameters in a Noisy Transmission Environment

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IEEE TRANSACTIONS ON BROADCASTING 2017年第3期63卷 463-478页

作者： Swaminathan, R. Madhukumar, A. S. Nanyang Technol Univ Sch Comp Sci & Engn Singapore 639798 Singapore

Channel encoder, which includes a forward error correcting (FEC) code followed by an interleaver, plays a vital role in improving the error performance of digital storage and communication systems. In most of the applications, the FEC code and interleaver parameters are known at the receiver to decode and de-interleave the information bits, respectively. But the blind/semi-blind estimation of code and interleaver parameters at the receiver will provide additional advantages in applications, such as adaptive modulation and coding, cognitive radio, non-cooperative systems, etc. The algorithms for the blind estimation of code parameters at the receiver had previously been proposed and investigated for known FEC codes. In this paper, we propose algorithms for the joint recognition of the type of FEC codes and interleaver parameters without knowing any information about the channel encoder. The proposed algorithm classify the incoming data symbols among block coded, convolutional coded, and uncoded symbols. Further, we suggest analytical and histogram approaches for setting the threshold value to perform code classification and parameter estimation. It is observed from the simulation results that the code classification and interleaver parameter estimation are performed successfully over erroneous channel conditions. The proposed histogram approach is more robust against the analytical approach for noisy transmission environment and system latency is one of the important challenges for the histogram approach to achieve better performance.

关键词： adaptive modulation and coding blind/semiblind estimation block interleaver cognitive radio forward error correcting (FEC) code

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Bandwidth-efficient bit-interleaved coded cooperative communications

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WIRELESS PERSONAL COMMUNICATIONS 2008年第3期46卷 247-268页

作者： Nguyen, Hieu T. Nguyen, Ha H. Le-Ngoc, Tho Univ Saskatchewan Dept Elect & Comp Engn Saskatoon SK S7N 5A9 Canada McGill Univ Dept Elect & Comp Engn Montreal PQ H3A 2A7 Canada

A cooperative coding scheme using M-ary modulation for high spectral efficiency and repetitive information transmission for diversity improvement is proposed. The encoder is a parallel concatenation of two bit-interleaved coded M-ary modulators (BICM) with scalable repetition of information symbols. As a result, the fraction of repeated information and the spectral efficiency of M-ary modulation can be used for bandwidth-performance tradeoff. Performance analysis is carried out to verify the performance advantage of the proposed system. In particular, analytical and simulation results in various block fading scenarios show that for a given bandwidth efficiency, a proper selection of the fraction of repeated information and the spectral efficiency of M-ary modulation can provide a large performance improvement.

关键词： cooperative communications coded modulation performance analysis block fading channel adaptive modulation and coding

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