In this paper, we have compared the performance of joint network channel coding (JNCC) for multicast relay network using low density parity check (LDPC) codes and Convolutional codes as channel codes while exclusi...In this paper, we have compared the performance of joint network channel coding (JNCC) for multicast relay network using low density parity check (LDPC) codes and Convolutional codes as channel codes while exclusive or (XOR) network coding used at the intermediate relay nodes. Multicast relay transmission is a type of transmission scheme in which two fixed relay nodes contribute in the second hop of end-to-end transmission between base transceiver station (BTS) and a pair of mobile stations. We have considered one way and two way multicast scenarios to evaluate the bit error rate (BER) and throughput performance. It has been shown that when using XOR network coding at the intermediate relay nodes, the same transmission becomes possible in less time slots hence throughput performance can be improved. Moreover we have also discussed two possible scenarios in the proposed system model, in which both diversity and multiplexing gain has been considered. It is worth notifying that BER and throughput achieved for LDPC codes is better than Convolutional codes for all the schemes discussed.展开更多
Wireless cooperative communications require appropriate power allocation (PA) between the source and relay nodes. In selfish cooperative communication networks, two partner user nodes could help relaying information...Wireless cooperative communications require appropriate power allocation (PA) between the source and relay nodes. In selfish cooperative communication networks, two partner user nodes could help relaying information for each other, but each user node has the incentive to consume his power solely to decrease its own symbol error rate (SER) at the receiver. In this paper, we propose a fair and efficient PA scheme for the decode-and-forward cooperation protocol in selfish cooperative relay networks. We formulate this PA problem as a two-user cooperative bargaining game, and use Nash bargaining solution (NBS) to achieve a win-win strategy for both partner users. Simulation results indicate that the NBS is fair in that the degree of cooperation of a user only depends on how much contribution its partner can make to decrease its SER at the receiver, and efficient in the sense that the SER performance of both users could be improved through the game.展开更多
In this paper, we present a non-transferable utility coalition graph game (NTU-CGG) based resource allocation scheme with relay selection for a downlink orthogonal frequency division multiplexing (OFDMA) based cog...In this paper, we present a non-transferable utility coalition graph game (NTU-CGG) based resource allocation scheme with relay selection for a downlink orthogonal frequency division multiplexing (OFDMA) based cognitive radio networks to maximize both system throughput and system faimess. In this algorithm, with the assistance of others SUs, SUs with less available channels to improve their throughput and fairness by forming a directed tree graph according to spectrum availability and traffic demands of SUs. So this scheme can effectively exploit both space and frequency diversity of the system. Performance results show that, NTU-CGG significantly improves system faimess level while not reducing the throughput comparing with other existing algorithms.展开更多
While the Network Coding cooperative relaying (NC-relaying) has the merit of high spectral efficiency,Superposition Coding relaying (SC-relaying) has the merit of high throughput. In this paper,a novel concept,coded c...While the Network Coding cooperative relaying (NC-relaying) has the merit of high spectral efficiency,Superposition Coding relaying (SC-relaying) has the merit of high throughput. In this paper,a novel concept,coded cooperative relaying,is presented,which is a unified scheme of the NC-relaying and SC-relaying. For the SC-relaying strategy which can be considered one-way coded relaying scheme with multi-access channel,the close-form solution of the outage probabilities of the basic signal and additional signal are obtained firstly. Secondly,the Diversity-and-Multiplexing Tradeoff (DMT) characteristics of basic signal and additional signal are investigated entirely as well as the optimal close-form solutions. The compared numerical analysis shows the evaluation error of throughput based on the close-form solution is about 0.15 nats,which is within the acceptable error range. Due to the mutual effect between the both source signals,the available maximal values of the two multiplexing gains are less than 1.展开更多
This paper investigates the resource scheduling for heterogeneous vehicular networks, where some moving vehicles are selected and scheduled as helping relays to assist information transmission between the roadside inf...This paper investigates the resource scheduling for heterogeneous vehicular networks, where some moving vehicles are selected and scheduled as helping relays to assist information transmission between the roadside infrastructure and other moving vehicles. For such a system, we propose a mobile-service based max-min fairness resource scheduling scheme, where service amount which is more suitable for high mobility scenarios is adopted to characterize the information transmission capacity of the links and the max-min criteria is adopted to meet the fairness requirement of the moving vehicles. Simulation results demonstrate the effectiveness of our proposed scheme. It is shown that our proposed scheme archives higher throughput and better fairness compared with random scheduling scheme and non-relaying scheme.展开更多
Cooperative relaying techniques can greatly improve the capacity of the multiple input and multiple output (MIMO) wireless system. The transmit power allocation (TPA) strategies for various relaying protocols have...Cooperative relaying techniques can greatly improve the capacity of the multiple input and multiple output (MIMO) wireless system. The transmit power allocation (TPA) strategies for various relaying protocols have become very important for improving the energy efficiency. This article proposes novel TPA schemes in the MIMO cooperative relaying system. Two different scenarios are considered. One is the hybrid decode-and-forward (HDF) protocol in which the zero-forcing (ZF) process is operated on relays, and the other is the decode-and-forward (DF) protocol with relay node and antenna selection strategies. The simulation results indicate that the proposed schemes can bring about significant capacity gain by exploiting the nature of the relay link. Additionally, the proposed TPA scheme in the HDF system can achieve the same capacity as the equal TPA with fewer relay nodes used. Finally, the capacity gain with the proposed schemes increases when the distribution range of relay nodes expands.展开更多
In wireless sensor networks, the traditional multi-relay incremental cooperative relaying (MIR) scheme could improve the system throughput over the fading channel enormously by exploiting multiple relay nodes to retra...In wireless sensor networks, the traditional multi-relay incremental cooperative relaying (MIR) scheme could improve the system throughput over the fading channel enormously by exploiting multiple relay nodes to retransmit the copy of the source packet to the destination in turn, but increase the energy consumption and transmission delay. In order to mitigating the energy consumption and transmission delay, this paper proposes a new cooperative relaying scheme termed as incremental-selective relaying with best-relay selection (ISR), which selects the best relay node from the candidate relays to retransmit the packet to the destination only when the direct transmission between the source and the destination is not successful. Expressions of normalized throughput, normalized delay and energy efficiency for the ISR and MIR systems are derived respectively and their performances are compared through simulations. The results show that normalized throughput, normalized delay and energy efficiency for the ISR system all outperform the corresponding performances of the MIR system. Especially, there are different the optimal number of relays which can maximize the energy efficiency of system.展开更多
In wireless relaying networks, the traditional incremental cooperative relaying scheme (IR) could improve the system throughput enormously over fading channels by exploiting relay nodes to retransmit the source data p...In wireless relaying networks, the traditional incremental cooperative relaying scheme (IR) could improve the system throughput enormously over fading channels by exploiting relay nodes to retransmit the source data packet to the destination. In order to enhance the system throughput over time-varying fading channels, this paper proposes an adaptive incremental cooperative re-laying scheme (AIR) based on adaptive modulation and coding, which implements adaptive rate transmission for the source and relay nodes according to channel state information. We derive expressions for the AIR system throughput, and then give a gradient-based search algorithm to find the optimized adaptive solution for the AIR system by maximizing throughput subject to the constraint of packet error rate at the data link layer. The results indicate that throughput of AIR system outperforms that of traditional IR system greatly for any SNR value.展开更多
In wireless networks, cooperative relaying could improve throughput by exploiting diversity. In order to reduce the amount of feedback for the channel gain, a semi-distributed scheme based on the relay feasible condit...In wireless networks, cooperative relaying could improve throughput by exploiting diversity. In order to reduce the amount of feedback for the channel gain, a semi-distributed scheme based on the relay feasible condition is proposed. Each relay node can measure its backward and forward channel gains. If both the channel gains are larger than a pre-defined threshold, this relay node is feasible. The final decision on the best relay selection is still given by the base station. Besides, the switch-and-examine relay selection scheme, which selects the first feasible relay node, is also investigated. Simulation results are presented to illustrate the advantage of two proposed schemes.展开更多
文摘In this paper, we have compared the performance of joint network channel coding (JNCC) for multicast relay network using low density parity check (LDPC) codes and Convolutional codes as channel codes while exclusive or (XOR) network coding used at the intermediate relay nodes. Multicast relay transmission is a type of transmission scheme in which two fixed relay nodes contribute in the second hop of end-to-end transmission between base transceiver station (BTS) and a pair of mobile stations. We have considered one way and two way multicast scenarios to evaluate the bit error rate (BER) and throughput performance. It has been shown that when using XOR network coding at the intermediate relay nodes, the same transmission becomes possible in less time slots hence throughput performance can be improved. Moreover we have also discussed two possible scenarios in the proposed system model, in which both diversity and multiplexing gain has been considered. It is worth notifying that BER and throughput achieved for LDPC codes is better than Convolutional codes for all the schemes discussed.
基金supported by National Natural Science Foundation of China (No. 60972059)Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)+3 种基金Fundamental Research Funds for the Central Universities of China (Nos. 2010QNA27 and 2011QNB26)China Postdoctoral Science Foundation (No. 20100481185)the Ph. D. Programs Foundation of Ministry of Education of China (Nos. 20090095120013 and 20110095120006)Talent Introduction Program, and Young Teacher Sailing Program of China University of Mining and Technology
文摘Wireless cooperative communications require appropriate power allocation (PA) between the source and relay nodes. In selfish cooperative communication networks, two partner user nodes could help relaying information for each other, but each user node has the incentive to consume his power solely to decrease its own symbol error rate (SER) at the receiver. In this paper, we propose a fair and efficient PA scheme for the decode-and-forward cooperation protocol in selfish cooperative relay networks. We formulate this PA problem as a two-user cooperative bargaining game, and use Nash bargaining solution (NBS) to achieve a win-win strategy for both partner users. Simulation results indicate that the NBS is fair in that the degree of cooperation of a user only depends on how much contribution its partner can make to decrease its SER at the receiver, and efficient in the sense that the SER performance of both users could be improved through the game.
基金supported by the National Natural Science Funds of China for Young Scholar(61001115)the Beijing Natural Science Foundation of China(4102044)the National Natural Science Foundation of China(61271182)
文摘In this paper, we present a non-transferable utility coalition graph game (NTU-CGG) based resource allocation scheme with relay selection for a downlink orthogonal frequency division multiplexing (OFDMA) based cognitive radio networks to maximize both system throughput and system faimess. In this algorithm, with the assistance of others SUs, SUs with less available channels to improve their throughput and fairness by forming a directed tree graph according to spectrum availability and traffic demands of SUs. So this scheme can effectively exploit both space and frequency diversity of the system. Performance results show that, NTU-CGG significantly improves system faimess level while not reducing the throughput comparing with other existing algorithms.
基金Supported by the 973 Project of China (No.2007CB 310607)the 863 Key Project of "Key Technologies and System for Trunk Communication Based on TD-SCDMA" of China (No.2009AA011302)the Open Research Fund of National Mobile Communications Research Lab,Southeast University (N200604)
文摘While the Network Coding cooperative relaying (NC-relaying) has the merit of high spectral efficiency,Superposition Coding relaying (SC-relaying) has the merit of high throughput. In this paper,a novel concept,coded cooperative relaying,is presented,which is a unified scheme of the NC-relaying and SC-relaying. For the SC-relaying strategy which can be considered one-way coded relaying scheme with multi-access channel,the close-form solution of the outage probabilities of the basic signal and additional signal are obtained firstly. Secondly,the Diversity-and-Multiplexing Tradeoff (DMT) characteristics of basic signal and additional signal are investigated entirely as well as the optimal close-form solutions. The compared numerical analysis shows the evaluation error of throughput based on the close-form solution is about 0.15 nats,which is within the acceptable error range. Due to the mutual effect between the both source signals,the available maximal values of the two multiplexing gains are less than 1.
基金supported by the Chinese Postdoctoral Science Foundation No. 2015M570937the Open Research Fund of National Mobile Communications Research Laboratory,Southeast University No. 2014D03+2 种基金the National High-Tech R&D Program(863 Program) No.2015AA010301the National Natural Science Foundation of Chinaunder Grant No.61572072the Fundamental Research Funds for the Central Universities "Research on the System of Personalized Education using Big Data"
文摘This paper investigates the resource scheduling for heterogeneous vehicular networks, where some moving vehicles are selected and scheduled as helping relays to assist information transmission between the roadside infrastructure and other moving vehicles. For such a system, we propose a mobile-service based max-min fairness resource scheduling scheme, where service amount which is more suitable for high mobility scenarios is adopted to characterize the information transmission capacity of the links and the max-min criteria is adopted to meet the fairness requirement of the moving vehicles. Simulation results demonstrate the effectiveness of our proposed scheme. It is shown that our proposed scheme archives higher throughput and better fairness compared with random scheduling scheme and non-relaying scheme.
基金supported by Ericsson Company,the National Natural Science Foundation of China(60496312)the Hi-Tech Research and Development Programm of China(2006AA01Z260)
文摘Cooperative relaying techniques can greatly improve the capacity of the multiple input and multiple output (MIMO) wireless system. The transmit power allocation (TPA) strategies for various relaying protocols have become very important for improving the energy efficiency. This article proposes novel TPA schemes in the MIMO cooperative relaying system. Two different scenarios are considered. One is the hybrid decode-and-forward (HDF) protocol in which the zero-forcing (ZF) process is operated on relays, and the other is the decode-and-forward (DF) protocol with relay node and antenna selection strategies. The simulation results indicate that the proposed schemes can bring about significant capacity gain by exploiting the nature of the relay link. Additionally, the proposed TPA scheme in the HDF system can achieve the same capacity as the equal TPA with fewer relay nodes used. Finally, the capacity gain with the proposed schemes increases when the distribution range of relay nodes expands.
文摘In wireless sensor networks, the traditional multi-relay incremental cooperative relaying (MIR) scheme could improve the system throughput over the fading channel enormously by exploiting multiple relay nodes to retransmit the copy of the source packet to the destination in turn, but increase the energy consumption and transmission delay. In order to mitigating the energy consumption and transmission delay, this paper proposes a new cooperative relaying scheme termed as incremental-selective relaying with best-relay selection (ISR), which selects the best relay node from the candidate relays to retransmit the packet to the destination only when the direct transmission between the source and the destination is not successful. Expressions of normalized throughput, normalized delay and energy efficiency for the ISR and MIR systems are derived respectively and their performances are compared through simulations. The results show that normalized throughput, normalized delay and energy efficiency for the ISR system all outperform the corresponding performances of the MIR system. Especially, there are different the optimal number of relays which can maximize the energy efficiency of system.
文摘In wireless relaying networks, the traditional incremental cooperative relaying scheme (IR) could improve the system throughput enormously over fading channels by exploiting relay nodes to retransmit the source data packet to the destination. In order to enhance the system throughput over time-varying fading channels, this paper proposes an adaptive incremental cooperative re-laying scheme (AIR) based on adaptive modulation and coding, which implements adaptive rate transmission for the source and relay nodes according to channel state information. We derive expressions for the AIR system throughput, and then give a gradient-based search algorithm to find the optimized adaptive solution for the AIR system by maximizing throughput subject to the constraint of packet error rate at the data link layer. The results indicate that throughput of AIR system outperforms that of traditional IR system greatly for any SNR value.
文摘In wireless networks, cooperative relaying could improve throughput by exploiting diversity. In order to reduce the amount of feedback for the channel gain, a semi-distributed scheme based on the relay feasible condition is proposed. Each relay node can measure its backward and forward channel gains. If both the channel gains are larger than a pre-defined threshold, this relay node is feasible. The final decision on the best relay selection is still given by the base station. Besides, the switch-and-examine relay selection scheme, which selects the first feasible relay node, is also investigated. Simulation results are presented to illustrate the advantage of two proposed schemes.