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Transmission of Visual Data over Wireless Fading Channel in Real-Time Systems Based on superposition coding Scheme

ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2013年第6期38卷 1459-1469页

作者： Tahir, Yaseen H. Ng, Chee Kyun Noordin, Nor K. Ali, Borhanuddin Mohd. Fdn Tech Educ Elect Power Engn Dept Basrah Tech Coll Basrah Iraq Univ Putra Malaysia Dept Comp & Commun Syst Engn Fac Engn Upm Serdang 43400 Selangor Malaysia

Real-time visual applications are among the most important requirements in the next generation wireless communication systems. In these applications, the transmitted data comprise different layers with different importance levels based on their influence on the reception quality. Furthermore, the real-time transmission nature of these applications makes them sensitive to data losses and transmission delay. To address these issues, an efficient superposition adaptive modulation and coding system, for the optimal system performance, is proposed in this paper. The proposed system switches its modulation and coding scheme adaptively to select the suitable modulation order and coding rate that best match with the instantaneous channel condition. The channel state information is estimated in receiver and fed back to transmitter. In such method, better performances in both data rate and bit error rate (BER) can be attained. Here, the source data are divided into different priority layers with different importance. Each layer bit stream is sent with specific error protection level against channel corruption. The highest error protection level is assigned to the highest priority layer, and vice versa. The modulated bit streams of all layers are then superimposed together and transmitted via Rayleigh fading channel. At the receiver side, a specific multi-stage decoding receiver is used to reconstruct the source data which demodulates the layers in the order of their priorities. Simulation results show that the proposed system provides up to 18 dB SNR and 46 % data rate gains, respectively, compared to the traditional BPSK scheme at BER of 10(-4).

关键词： Real-time wireless visual data transmission Fading channel superposition coding UEP AMC

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Sum Rate Maximizing superposition coding Scheme for a Two-User Wireless Relay System

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IEEE COMMUNICATIONS LETTERS 2011年第4期15卷 428-430页

作者： Kaneko, Megumi Hayashi, Kazunori Sakai, Hideaki Kyoto Univ Grad Sch Informat Sakyo Ku Kyoto 6068501 Japan

A wireless system is considered where users are served in Downlink (DL) by one Base Station (BS) and one Relay Station (RS). A scheme based on superposition coding (SC) is proposed, where two users are served by three superposed layers that take advantage of the three available links for maximizing sum rate. With the derived optimal allocation parameters, our scheme outperforms benchmark schemes for sum-rate and fairness, making it very efficient for scheduling multiple users.

关键词： Relay system radio resource allocation superposition coding

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Conditions for Optimality of superposition coding in Discrete Memoryless Broadcast Channels 25

Conditions for Optimality of Superposition Coding in Discret...

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25th National Conference on Communications (NCC)

作者： Krishnamurthy, Harikumar Hegde, Parikshit Thangaraj, Andrew Indian Inst Technol Madras Dept Elect Engn Chennai Tamil Nadu India

ISBN: (纸本)9781538692868

The capacity region of general discrete-memoryless broadcast channels (DMBCs) with two receivers is an open problem of considerable research interest. The optimality of superposition coding in three specific cases of the DMBC is considered. For a DMBC with binary input, symmetric output and output cardinality at most 3, superposition coding is shown to be optimal. For equal-capacity DMBCs with any input cardinality, superposition coding is shown to be suboptimal if each channel has a capacity-achieving input distribution that is not capacity-achieving for the other channel. For an equal-capacity DMBC with binary input, superposition coding is shown to be optimal if and only if the two channels are more-capable comparable even without utput symmetry. These results improve upon the previously known conditions for optimality of superposition coding in DMBCs.

关键词： Broadcast channels Capacity region superposition coding

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Joint Proportional Fairness Admission Control and superposition coding for OFDMA Networks

Joint Proportional Fairness Admission Control and Superposit...

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20th International Conference on Telecommunications (ICT)

作者： Abbes, Yosra Najeh, Sameh Besbes, Hichem Univ Carthage SupCom Res Lab COSIM Carthage Tunisia

ISBN: (纸本)9781467364263

In this paper, we aim to design an OFDMA frame-based resource allocation scheme allowing the power consumption minimization, the throughput enhancement and the queue's stability. We have proposed a novel proportional fairness admission control strategy in order to guarantee the desired QoS for each user. To increase the number of admitted users, we investigate a joint superposition coding and admission control process permitting to further exploit the multiuser diversity. Furthermore, we have suggested a power and bandwidth allocation scheme permitting to minimize power consumption while ensuring buffer's stability and satisfying the QoS requirements of users in a heavy load context. Numerical studies are conducted to evaluate the performance of the proposed algorithms in terms of served user and power consumption.

关键词： Terms resource allocation OFDMA systems buffer's stability power consumption superposition coding

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Pricing and Optimal Power Allocation in Collaborative Primary-Secondary Transmission Using superposition coding

Pricing and Optimal Power Allocation in Collaborative Primar...

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IEEE Region 10 Conference on TENCON 2010

作者： Kim, Insook Kim, Dongwoo Hanyang Univ Dept Elect Engn & Comp Sci Ansan 426791 South Korea

ISBN: (纸本)9781424468904

We study a problem of pricing-based power allocation in collaborative primary-secondary transmission using superposition coding (SC) where secondary power is assigned to primary and secondary signals with fraction alpha and (1 - alpha), respectively. The power allocation problem for the secondary user considering price of power level is formulated as a convex optimization problem. And an optimal power allocation for a known primary's pricing policy is provided. For the primary user, a convex optimization problem is formulated to find an optimal pricing policy. With numerical examples, optimal power allocation solutions and pricing policy for different network topologies are provided.

关键词： collaborative primary-secondary transmission encoding network topology optimal power allocation power level pricing pricing superposition coding

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A Unifying Order-Theoretic Framework for superposition coding: Polymatroidal Structure and Optimality in the Multiple-Access Channel With General Message Sets

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IEEE TRANSACTIONS ON INFORMATION THEORY 2017年第1期63卷 21-37页

作者： Romero, Henry P. Varanasi, Mahesh K. Univ Colorado Dept Appl Math Boulder CO 80303 USA MIT Lincoln Lab Lexington MA 02421 USA Univ Colorado Elect Comp & Energy Engn Dept Boulder CO 80303 USA

Two different random coding techniques, both referred to as superposition coding in the literature, have been widely used to obtain inner bounds for the capacity regions of various communication networks. In one, auxiliary codewords are generated independently, and in the other, they are generated in a dependent manner. Using the multiple-access channel with general message sets as a case study, we place the two techniques under a common, order-theoretic framework. The key attribute of this framework is that it explicitly accounts for the acyclic direction and transitivity of the possible auxiliary codeword dependencies, leading to three significant discoveries. First, with respect to a fixed coding distribution, the set of rates achievable by superposition coding with dependent auxiliary codeword generation forms a polymatroid, thereby generalizing the same previously known result for superposition coding with independent auxiliary codewords. Second, we obtain a large class of superposition coding schemes by intermingling dependent and independent auxiliary codeword generation, and demonstrate that the constituent polyhedral achievable rate regions are also polymatroids in each case. The third discovery is that, in the multiple-access channel with general message sets, each associated superposition coding inner bound attains the capacity region. These results demonstrate a tradeoff between the complexity of dependencies in auxiliary codeword generation and that of the function that maps them into transmitted codewords.

关键词： General message sets multiple-access channel order theory polymatroids superposition coding

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Efficient Optimization Algorithms for Multi-User Beamforming With superposition coding

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IEEE TRANSACTIONS ON COMMUNICATIONS 2018年第12期66卷 5902-5915页

作者： Shi, Xiaoyan Thompson, John S. Liu, Rongke Safari, Majid Cao, Pan Univ Edinburgh Inst Digital Commun Edinburgh EH3 9JL Midlothian Scotland Beihang Univ Beijing 100191 Peoples R China Beihang Univ Sch Elect & Informat Engn Beijing 100191 Peoples R China Univ Hertfordshire Sch Engn & Technol Hatfield AL10 9AB Herts England

Channel asymmetry and channel correlation are frequently encountered in wireless communication systems. Orthogonal transmission schemes are usually inefficient in dealing with these problems. In this paper, in order to boost the throughput performance for multiple-input multiple-output broadcast communications in the presence of channel asymmetry and/or channel correlation, we study optimization algorithms for multi-user superposition coding beamforming (SCBF). Starting with solving the minimum power optimization problem for the two-user case, we derive the optimal solution structure of the problem and two types of dedicated algorithms that could efficiently find the optimal solutions with all parameter setups. Extensions are then made to the same problem with the signals of more than two users multiplexed in the power domain as well as to the rate region computation problem. Finally, to adapt our algorithms to more general cases, novel hybrid precoding schemes are proposed, where certain user grouping strategy is used to combine zero-forcing beamforming and SCBF. Numerical simulations are provided to show that with our algorithms, a considerable performance gain is achieved by SCBF compared to the other orthogonal transmission methods.

关键词： Optimizations beamforming superposition coding channel correlations second-order conic programs

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A Practical Compress-and-Forward Relay Scheme Based on superposition coding

A Practical Compress-and-Forward Relay Scheme Based on Super...

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14th IEEE International Conference on Communication Technology (ICCT)

作者： Liu, Yang Xu, Wenbo Niu, Kai He, Zhiqiang Tian, Baoyu Beijing Univ Posts & Telecommun Key Lab Univ Wireless Commun Minist Educ Beijing Peoples R China

ISBN: (纸本)9781467321013;9781467321006

Compress-and-forward (CF) is one of the protocols in cooperative communication and has drawn much attention. In CF scheme, the relay compresses and transmits the received signals to the destination, where Wyner-Ziv coding is considered as an efficient way to compress the signal with side information available. Since the current research of superposition coding for Wyner-Ziv problem only remains in theory, we design a practical CF scheme in half-duplex mode by using the technique of superposition coding and provide specific coding strategy for it. The relay compresses the received signal by the quantization method based on superposition coding, and then the destination performs a joint decoding to recover the original message. Simulations show that our proposed scheme outperforms the conventional CF scheme with scalar quantization at the relay. This coding strategy can be easily extended to the scenarios of fading channels, which are more practical in wireless communication.

关键词： compress-and-forward relay channel superposition coding quantization Wyner-Ziv coding

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High-Throughput Routing with superposition coding and Successive Interference Cancellation

High-Throughput Routing with Superposition Coding and Succes...

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IEEE International Conference on Communications (ICC)

作者： Su, Xueyuan Chan, Sammy Yale Univ Dept Comp Sci New Haven CT 06511 USA City Univ Hong Kong Dept Elect Engn Kowloon Peoples R China

ISBN: (纸本)9781612842332

Network coding aware routing protocols have been an interesting research topic in recent years. In this paper, we explore similar routing gains with physical layer coding techniques. A source routing protocol S3 is proposed to be implemented with a routing metric called iETT. By extending the traditional ETT measurement, iETT provides a simple way to make the routing protocol interference-aware. To further enable superposition coding and successive interference cancellation, S3 uses iETT to explore physical layer coding opportunities and measure potential gains in network throughput. Experimental evaluations confirm the effectiveness of iETT and S3. Significant improvements in network throughput are observed in both single-path and multi-path routing scenarios.

关键词： Wireless mesh networks source routing superposition coding successive interference cancellation

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Efficient Power Allocation for Video over superposition coding

Efficient Power Allocation for Video over Superposition Codi...

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IEEE 27th International Conference on Advanced Information Networking and Applications (IEEE AINA)

作者： Lau, Chun Pong Jamshaid, Kamran Shihada, Basem King Abdullah Univ Sci & Technol Comp Elect & Math Sci & Engn Div Thuwal 239556900 Saudi Arabia

ISBN: (纸本)9781467355506

In this paper we consider a wireless multimedia system by mapping scalable video coded (SVC) bitstream upon superposition coded (SPC) signals, referred to as (SVC-SPC) architecture. Empirical experiments using a software-defined radio (SDR) emulator are conducted to gain a better understanding of its efficiency, specifically, the impact of the received signal due to different power allocation ratios. Our experimental results show that to maintain high video quality, the power allocated to the base layer should be approximately four times higher than the power allocated to the enhancement layer.

关键词： power splitting superposition coding Videotapes received signal BASE COURSE MULTI-MEDIA SYSTEM Energy sources bit stream scalable video

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