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Cross-layer Theoretical Analysis of NC-aided Cooperative ARQ Protocols in Correlated Shadowed Environments (Extended Version)  [PDF]
Angelos Antonopoulos,Aris S. Lalos,Marco Di Renzo,Christos Verikoukis
Computer Science , 2014,
Abstract: In this paper, we propose a cross-layer analytical model for the study of Network Coding (NC)-based Automatic Repeat reQuest (ARQ) Medium Access Control (MAC) protocols in correlated slow faded (shadowed) environments, where two end nodes are assisted by a cluster of relays to exchange data packets. The goal of our work is threefold: i) to provide general Physical (PHY) layer theoretical expressions for estimating crucial network parameters (i.e., network outage probability and expected size of the active relay set), applicable in two-way communications, ii) to demonstrate how these expressions are incorporated in theoretical models of the upper layers (i.e., MAC), and iii) to study the performance of a recently proposed NC-aided Cooperative ARQ (NCCARQ) MAC protocol under correlated shadowing conditions. Extensive Monte Carlo experiments have been carried out to validate the efficiency of the developed analytical model and to investigate the realistic performance of NCCARQ. Our results indicate that the number of active relays is independent of the shadowing correlation in the wireless links and reveal intriguing trade-offs between throughput and energy efficiency, highlighting the importance of cross-layer approaches for the assessment of cooperative MAC protocols.
Goodput Maximization in Cooperative Networks with ARQ  [PDF]
Qing Chen,Mustafa Cenk Gursoy
Mathematics , 2010,
Abstract: In this paper, the average successful throughput, i.e., goodput, of a coded 3-node cooperative network is studied in a Rayleigh fading environment. It is assumed that a simple automatic repeat request (ARQ) technique is employed in the network so that erroneously received codeword is retransmitted until successful delivery. The relay is assumed to operate in either amplify-and-forward (AF) or decode-and-forward (DF) mode. Under these assumptions, retransmission mechanisms and protocols are described, and the average time required to send information successfully is determined. Subsequently, the goodput for both AF and DF relaying is formulated. The tradeoffs and interactions between the goodput, transmission rates, and relay location are investigated and optimal strategies are identified.
Network Coding-Based Cooperative ARQ Scheme  [PDF]
Angelos Antonopoulos,Christos Verikoukis
Computer Science , 2012, DOI: 10.1109/icc.2011.5963256
Abstract: In this paper we introduce a novel Automatic Repeat reQuest (ARQ) scheme for cooperative wireless networks. Our scheme adopts network coding techniques in order to enhance the total bandwidth of the network by minimizing the total number of transmissions. The performance of the proposed approach is evaluated by means of computer simulations and compared to other cooperative schemes, while an analytical solution is provided to validate the results.
Cooperative Network Coded ARQ Strategies for Two Way Relay Channel  [PDF]
Rasit Tutgun,Emre Aktas
Computer Science , 2013,
Abstract: In this paper, novel cooperative automatic repeat request (ARQ) methods with network coding are proposed for two way relaying network. Upon a failed transmission of a packet, the network enters cooperation phase, where the retransmission of the packets is aided by the relay node. The proposed approach integrates network coding into cooperative ARQ, aiming to improve the network throughput by reducing the number of retransmissions. For successive retransmission, three different methods for choosing the retransmitting node are considered. The throughput of the methods are analyzed and compared. The analysis is based on binary Markov channel which takes the correlation of the channel coefficients in time into account. Analytical results show that the proposed use of network coding result in throughput performance superior to traditional ARQ and cooperative ARQ without network coding. It is also observed that correlation can have significant effect on the performance of the proposed cooperative network coded ARQ approach. In particular the proposed approach is advantageous for slow to moderately fast fading channels.
A Diversity-Multiplexing-Delay Tradeoff of ARQ Protocols in The Z-interference Channel  [PDF]
Mohamed S. Nafea,D. Hamza,Karim G. Seddik,Mohammed Nafie,Hesham El Gamal
Mathematics , 2012,
Abstract: In this work, we analyze the fundamental performance tradeoff of the single-antenna Automatic Retransmission reQuest (ARQ) Z-interference channel (ZIC). Specifically, we characterize the achievable three-dimensional tradeoff between diversity (reliability), multiplexing (throughput), and delay (maximum number of retransmissions) of two ARQ protocols: A non-cooperative protocol and a cooperative one. Considering no cooperation exists, we study the achievable tradeoff of the fixed-power split Han-Kobayashi (HK) approach. Interestingly, we demonstrate that if the second user transmits the common part only of its message in the event of its successful decoding and a decoding failure at the first user, communication is improved over that achieved by keeping or stopping the transmission of both the common and private messages. We obtain closed-form expressions for the achievable tradeoff under the HK splitting. Under cooperation, two special cases of the HK are considered for static and dynamic decoders. The difference between the two decoders lies in the ability of the latter to dynamically choose which HK special-case decoding to apply. Cooperation is shown to dramatically increase the achievable first user diversity.
Joint Adaptive Modulation-Coding and Cooperative ARQ for Wireless Relay Networks  [PDF]
Morteza Mardani,Jalil S. Harsini,Farshad Lahouti,Behrouz Eliasi
Mathematics , 2008,
Abstract: This paper presents a cross-layer approach to jointly design adaptive modulation and coding (AMC) at the physical layer and cooperative truncated automatic repeat request (ARQ) protocol at the data link layer. We first derive an exact closed form expression for the spectral efficiency of the proposed joint AMC-cooperative ARQ scheme. Aiming at maximizing this system performance measure, we then optimize an AMC scheme which directly satisfies a prescribed packet loss rate constraint at the data-link layer. The results indicate that utilizing cooperative ARQ as a retransmission strategy, noticeably enhances the spectral efficiency compared with the system that employs AMC alone at the physical layer. Moreover, the proposed adaptive rate cooperative ARQ scheme outperforms the fixed rate counterpart when the transmission modes at the source and relay are chosen based on the channel statistics. This in turn quantifies the possible gain achieved by joint design of AMC and ARQ in wireless relay networks.
Research on cooperative ARQ for two-hop and two-relay system

XIONG Ying,TANG Lun,CHEN Qian-bin,

计算机应用研究 , 2010,
Abstract: The paper proposed a new transmission scheme in cooperative communication system based on best relay selection: cooperative ARQ scheme for two-hop and two-relay. The scheme was a tradeoff between transmission delay and efficiency. The analysis of theory and simulation results show that, under time correlated Rayleigh fading channel, cooperative ARQ scheme for two-hop and two-relay can give the best performance gain compared with single relay cooperative ARQ system and two relay cooperative system, not only when the qualities of source and relay are good, but also when there is a bad fading in the link of source to relay.
ARQ Protocols for Two-Way Wireless Relay Systems: Design and Performance Analysis
Zhenyuan Chen,Qiushi Gong,Chao Zhang,Guo Wei
International Journal of Distributed Sensor Networks , 2012, DOI: 10.1155/2012/980241
Abstract: Two-way relay (TWR) communication, a new cooperation paradigm that allows two terminals to share one relay node to communicate with each other in two phases, has played an increasingly valuable role in wireless networks to meet the stringent throughput requirement. In this paper, we focus on the designing of automatic repeat-request (ARQ) protocols for the two-way wireless relay systems. According to different feedback schedules, we propose three basic ARQ protocols to improve the throughput of two-way relay systems, namely, relay-only ARQ (Ro-ARQ), terminal only ARQ (To-ARQ) and relay-terminal ARQ (RT-ARQ). Through analyzing the outage throughput of these three ARQ protocols, it is verified that all three protocols can improve the system performance. In addition, simulation results reveal that the RT-ARQ protocol has the closest performance to the theoretical throughput upperbound among all given methods without severe deterioration on system complexity.
Wireless Cooperative Networks: Protocols, Topologies and Performance  [cached]
álvaro Ricieri Castro e Souza,Mario Lemes Proen?a Jr,Taufik Abr?o
Semina : Ciências Exatas e Tecnológicas , 2011,
Abstract: This work analyzes the most common wireless cooperative network protocols, verifying potentialities and performance relative to the non cooperative methodology, also techniques that can maximize the performance, such as combining signal rules and relay selection. Furthermore, considerations are provided for the computational complexity of topologies, combining techniques and protocols of cooperative networks.
Cooperative Protocols for Random Access Networks  [PDF]
Georg B?cherer,Alexandre de Baynast
Mathematics , 2008,
Abstract: Cooperative communications have emerged as a significant concept to improve reliability and throughput in wireless systems. On the other hand, WLANs based on random access mechanism have become popular due to ease of deployment and low cost. Since cooperation introduces extra transmissions among the cooperating nodes and therefore increases the number of packet collisions, it is not clear whether there is any benefit from using physical layer cooperation under random access. In this paper, we develop new low complexity cooperative protocols for random access that outperform the conventional non cooperative scheme for a large range of signal-to-noise ratios.
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