In this paper,we derive the Symbol Error Probability(SEP)of cooperative systems with incremental relaying and Distributed Relay Selection(DRS).The relays remain idle when the Signal to Noise Ratio(SNR)between the sour...In this paper,we derive the Symbol Error Probability(SEP)of cooperative systems with incremental relaying and Distributed Relay Selection(DRS).The relays remain idle when the Signal to Noise Ratio(SNR)between the source and destination is larger than T.Otherwise,we activate a relay using DRS.Relay nodes transmit only if their SNR is larger than thresholdβ.If the SNRs of more than two relays is larger thanβ,there is a collision and the destination uses only the received signal from the source.If all relays have SNR less thanβ,no relay is chosen.Thresholdβis optimized to yield the lowest SEP at the destination.Our results are compared to centralized relay selection using opportunistic Amplify and Forward(OAF),Partial and Reactive Relay Selection(PRS and RRS).We compare our results to computer simulations for Rayleigh fading channels.展开更多
Wireless networks contain an inherent distributed spatial diversity that can be exploited by relays. Relay networks can take advantage of the broadcast-oriented nature of wireless transmission, but require more radio ...Wireless networks contain an inherent distributed spatial diversity that can be exploited by relays. Relay networks can take advantage of the broadcast-oriented nature of wireless transmission, but require more radio resource to transmit data for their multi-hop traits. Fortunately, incremental relaying technique, which can choose direct or multi-hop transmission adaptively, can efficiently utilize resource. In this article, the incremental transmission with amplify-and-forward (AF) relays is focused on. A practical hybrid-automatic retransmission request (HARQ) protocol is designed, and the related optimal relay selection strategy is proposed. To analyze the cooperative diversity of system with the proposed protocol, the capacity lower bound is deduced. Simulation and analytical results indicate that by adopting the optimal relay selection strategy, the system with the proposed HARQ protocol can achieve an order of cooperative diversity that equals the aggregated number of the relay and source nodes.展开更多
文摘In this paper,we derive the Symbol Error Probability(SEP)of cooperative systems with incremental relaying and Distributed Relay Selection(DRS).The relays remain idle when the Signal to Noise Ratio(SNR)between the source and destination is larger than T.Otherwise,we activate a relay using DRS.Relay nodes transmit only if their SNR is larger than thresholdβ.If the SNRs of more than two relays is larger thanβ,there is a collision and the destination uses only the received signal from the source.If all relays have SNR less thanβ,no relay is chosen.Thresholdβis optimized to yield the lowest SEP at the destination.Our results are compared to centralized relay selection using opportunistic Amplify and Forward(OAF),Partial and Reactive Relay Selection(PRS and RRS).We compare our results to computer simulations for Rayleigh fading channels.
基金supported by China Mobile Corporation Company (CMCC), the National Natural Science Foundation of China (60802082)the National Key Technology R&D Program of China(2008BAH30B11)the Research Fund for the Doctoral Program of Higher Education (200800131023)
文摘Wireless networks contain an inherent distributed spatial diversity that can be exploited by relays. Relay networks can take advantage of the broadcast-oriented nature of wireless transmission, but require more radio resource to transmit data for their multi-hop traits. Fortunately, incremental relaying technique, which can choose direct or multi-hop transmission adaptively, can efficiently utilize resource. In this article, the incremental transmission with amplify-and-forward (AF) relays is focused on. A practical hybrid-automatic retransmission request (HARQ) protocol is designed, and the related optimal relay selection strategy is proposed. To analyze the cooperative diversity of system with the proposed protocol, the capacity lower bound is deduced. Simulation and analytical results indicate that by adopting the optimal relay selection strategy, the system with the proposed HARQ protocol can achieve an order of cooperative diversity that equals the aggregated number of the relay and source nodes.