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Power Allocation for Cooperative Communications in Non-Orthogonal Cognitive Radio Vehicular Ad-Hoc Networks 被引量:1
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作者 Yancheng Ji Dan Sun +1 位作者 Xiaojun Zhu Danfeng Dong 《China Communications》 SCIE CSCD 2020年第11期91-99,共9页
To achieve the better system performance for cooperative communication in non-orthogonal cognitive radio vehicular adhoc networks(CR-VANETs),this paper investigates the power allocation considering the interference to... To achieve the better system performance for cooperative communication in non-orthogonal cognitive radio vehicular adhoc networks(CR-VANETs),this paper investigates the power allocation considering the interference to the main system in a controllable range.We propose a three-slot one-way vehicle system model where the mobile vehicle nodes complete information interaction with the assistance of other independent nodes by borrowing the unused radio spectrum with the primary networks.The end-to-end SNR relationship in overlay and underlay cognitive communication system mode are analyzed by using two forwarding protocol,namely,decode-and-forward(DF)protocol and amplify-and-forward(AF)protocol,respectively.The system outage probability is derived and the optimal power allocation factor is obtained via seeking the minimum value of the approximation of system outage probability.The analytical results have been confirmed by means of Monte Carlo simulations.Simulation results show that the proposed system performance in terms of outage under the optimal power allocation is superior to that under the average power allocation,and is also better than that under other power allocation systems. 展开更多
关键词 DECODE-AND-FORWARD AMPLIFY-AND-FORWARD outage probability optimal power allocation cooperative communication cognitive radio vehicular ad-hoc networks
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Power allocation and mode selection methods for cooperative communication in the rectangular tunnel 被引量:2
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作者 Zhai Wenyan Sun Yanjing +1 位作者 Xu Zhao Li Song 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第2期253-260,共8页
For the multipath fading on electromagnetic waves of wireless communication in the confined areas,the rectangular tunnel cooperative communication system was established based on the multimode channel model and the ch... For the multipath fading on electromagnetic waves of wireless communication in the confined areas,the rectangular tunnel cooperative communication system was established based on the multimode channel model and the channel capacity formula derivation was obtained.On the optimal criterion of the channel capacity,the power allocation methods of both amplifying and forwarding(AF) and decoding and forwarding(DF) cooperative communication systems were proposed in the limitation of the total power to maximize the channel capacity.The mode selection methods of single input single output(SISO) and single input multiple output(SIMO) models in the rectangular tunnel,through which the higher channel capacity can be obtained,were put forward as well.The theoretical analysis and simulation comparison show that,channel capacity of the wireless communication system in the rectangular tunnel can be effectively enhanced through the cooperative technology;channel capacity of the rectangular tunnel under complicated conditions is maximized through the proposed power allocation methods,and the optimal cooperative mode of the channel capacity can be chosen according to the cooperative mode selection methods given in the paper. 展开更多
关键词 Rectangular tunnel Multimode channel model Channel capacity cooperative communication power allocation Mode selection
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Optimal power allocation for amplify-and-forward in single relay non-cooperative systems
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作者 王仕果 Ji Hong 《High Technology Letters》 EI CAS 2010年第4期428-432,共5页
For a single-relay amplify-and-forward (AF) non-cooperative system,an optimal power proportionbetween source and relay is considered.Aiming to minimize end-to-end bit error rate (BER) and maximizeattainable rate,both ... For a single-relay amplify-and-forward (AF) non-cooperative system,an optimal power proportionbetween source and relay is considered.Aiming to minimize end-to-end bit error rate (BER) and maximizeattainable rate,both large-scale path loss and small-scale Rayleigh fading are taken into account.Aclosed form expression to allocate power in optimal proportion at source is obtained.Simulation resultsshow that the proposed scheme to distribute power can minimize BER under any channel conditions. 展开更多
关键词 amplify-and-forward (AF) optimal power allocation cooperative communication wireless relay
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Optimal power allocation to minimize SER for multinode amplify-and-forward cooperative communication systems 被引量:6
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作者 LIN Fei LIU Xi-mei +1 位作者 LUO Tao YUE Guang-xin 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2008年第4期14-18,23,共6页
An optimal power allocation (OPA) method with mean channel gains is proposed for a multinode amplify-and-forward cooperative communication system. By making use of M-PSK modulation, a closed-form symbol-error-rate ... An optimal power allocation (OPA) method with mean channel gains is proposed for a multinode amplify-and-forward cooperative communication system. By making use of M-PSK modulation, a closed-form symbol-error-rate (SER) formulation and corresponding upper bound are first derived. Subsequently the OPA method is utilized to minimize the SER. Comparison of the SER of the proposed OPA method with that of the equal power allocation (EPA) method, shows that the SER of both methods, which is approximately optimal performance, is almost the same when relays are near the source. OPA outperforms the EPA when the relays are near the middle between the source and destination or near the destination. The proposed OPA method depends only on the ratio of mean channel gains of the source-to-relay to those of the relay-to-destination. Extensive simulations are performed to validate the theoretical results. 展开更多
关键词 AMPLIFY-AND-FORWARD multinode cooperative communications SER power allocation
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Optimal Relay Assignment and Power Allocation for Cooperative Communications 被引量:1
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作者 谢鲲 曹建农 文吉刚 《Journal of Computer Science & Technology》 SCIE EI CSCD 2013年第2期343-356,共14页
Cooperative communication for wireless networks has gained a lot of recent interest due to its ability to mitigate fading with exploration of spatial diversity. In this paper, we study a joint optimization problem of ... Cooperative communication for wireless networks has gained a lot of recent interest due to its ability to mitigate fading with exploration of spatial diversity. In this paper, we study a joint optimization problem of jointly considering transmission mode selection, relay assignment and power allocation to maximize the capacity of the network through cooperative wireless communications. This problem is much more challenging than relay assignment considered in literature work which simply targets to maximize the transmission capacity for a single transmission pair. We formulate the problem as a variation of the maximum weight matching problem where the weight is a function over power values which must meet power constraints (VMWMC). Although VMWMC is a non-convex problem whose complexity increases exponentially with the number of relay nodes, we show that the duality gap of VMWMC is virtual zero. Based on this result, we propose a solution using Lagrange dual decomposition to reduce the computation complexity. We do simulations to evaluate the performance of the proposed solution. The results show that our solution can achieve maximum network capacity with much less computation time compared with exhaustive search, and our solution outperforms existing sub-optimal solutions that can only achieve much lower network capacity. 展开更多
关键词 cooperative communication network capacity dual decomposition relay assignment power allocation
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Joint Power Allocation and Beamforming for Cooperative Networks
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作者 Sondes Maadi Noureddine Hamdi 《International Journal of Communications, Network and System Sciences》 2011年第7期447-451,共5页
In this paper, we investigate power allocation problem with the use of transmit beamforming in a dual hop MISO (multiple input single output) relay channel. We consider either amplify and forward (AF) or decode and fo... In this paper, we investigate power allocation problem with the use of transmit beamforming in a dual hop MISO (multiple input single output) relay channel. We consider either amplify and forward (AF) or decode and forward (DF) cooperative protocols at the relay and optimize the power allocated to the relay and the source, under total transmit power constraint, to minimize the bit error rate (BER) of relaying system. Cooperative communication is viewed as a method for increasing diversity gain and reducing end to end path loss. The use of relay can create a virtual antenna array so that it allows users to exploit the advantages of multiple input multiple output (MIMO) techniques. In this work, we solve cooperative ratio, which is defined as the ratio power used for cooperative transmission over the total power. This approach is then compared to an equal power assignment method and its performance enhancement is verified by simulation results. 展开更多
关键词 Amplify and FORWARD Decode and FORWARD Transmit BEAMFORMING power allocation MISO cooperative communication
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Genetic-optimization framework for SVC transmission based on partial cooperative communication
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作者 Kai Zhao Yongcheng Sun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第5期861-870,共10页
A genetic-optimization framework based on the partial cooperation communication protocol is proposed for scalable video coding (SVC) stream transmission under multi-relay amplify and forward cooperative networks. Unli... A genetic-optimization framework based on the partial cooperation communication protocol is proposed for scalable video coding (SVC) stream transmission under multi-relay amplify and forward cooperative networks. Unlike traditional cooperative transmission schemes, the transmission mode for each coded unit in this new protocol can be switched flexibly between direct transmission and cooperative transmission. Obviously, under this protocol, the bandwidth efficiency and transmission robustness can be balanced adaptively according to the priority level of coded units and wireless channel fading characteristics. Based on this, a well-known genetic optimization algorithm-differential evolution is exploited here to find the jointly optimal transmission modes, power allocation and unequal error protection (UEP) channel coding strategies to minimize the end to end reconstructed video distortion. Extensive simulation results show that, compared with classical optimal cooperative UEP transmission schemes, the proposed optimized transmission framework based on the partial cooperative protocol can bring significant peak-signal-to-noise-ratio (PSNR) gains for the reconstructed video in a variety of channel bandwidth, power budget and test sequences. 展开更多
关键词 scalable video coding partial cooperative communication unequal error protection source-relay power allocation differential evolution
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Employing Power Allocation to Enhance Zero Forcing Scheme Advantages over Multi-Antenna Multiple Relay Networks
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作者 Abolfazl Falahati Y. Attar Izi 《International Journal of Communications, Network and System Sciences》 2012年第11期736-742,共7页
A multi-antenna multiple relay (MAMR) network is considered and a variation of two-hop zero-forcing amplify-forward relaying method is proposed. Deploying ZF method together with application of diagonal power allocati... A multi-antenna multiple relay (MAMR) network is considered and a variation of two-hop zero-forcing amplify-forward relaying method is proposed. Deploying ZF method together with application of diagonal power allocation matrices at the relays, it is shown that the overall MAMR network is simplified to M independent single antenna multiple relay (SAMR) networks, where M is the number of source and destination antennas. This enables to incorporate network beamforming proposed for SAMR networks. Accordingly, using the BER as the performance metric, we present simulation results to show the proposed approach outperforms the common ZF method addressed in the literature. 展开更多
关键词 cooperative communication MIMO MULTIPLE Antennas MULTIPLE Relay (MAMR) Networks Zero FORCING power allocation
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Relay Selection and Power Allocation in Amplify-and-Forward Cognitive Radio Systems Based on Spectrum Sharing
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作者 Daqian Zhao Zhizhong Zhang Fang Cheng 《Communications and Network》 2013年第3期380-385,共6页
In this paper, we consider a spectrum sharing scheme that is a joint optimization of relay selection and power allocation at the secondary transmitter, which aims to achieve the maximum possible throughput for the sec... In this paper, we consider a spectrum sharing scheme that is a joint optimization of relay selection and power allocation at the secondary transmitter, which aims to achieve the maximum possible throughput for the secondary user. This paper considers the scenario where the primary user is incapable of supporting its target signal-to-noise ratio (SNR). More especially, the secondary transmitter tries to assist the primary user with achieving its target SNR by cooperative amplify-and-forward (AF) relaying with two-phase. By exhaustive search for all candidate secondary transmitters, an optimal secondary transmitter can be selected, which not only can satisfy the primary user’s target SNR, but also maximize the secondary user’s throughput. The optimal secondary transmitter acts as a relay for the primary user by allocating a part of its power to amplify-and-forward the primary signal over the primary user’s licensed spectrum bands. At the same time, as a reward, the optimal secondary transmitter uses the remaining power to transmit its own signal over the remaining licensed spectrum bands. Thus, the secondary user obtains the spectrum access opportunities. Besides, there is no interference between the primary user and the secondary user. We study the joint optimization of relay selection and power allocation such that the secondary user’s throughput is maximized on the condition that it satisfies the primary user’s target SNR. From the simulation, it is shown that the joint optimization of relay selection and power allocation provides a significant throughput gain compared with random relay selection with optimal power allocation (OPA) and random relay selection with water-filling power allocation (WPA). Moreover, the simulation results also shown that our spectrum sharing scheme obtains the win-win solution for the primary system and the secondary system. 展开更多
关键词 Spectrum SHARING cooperative communication RELAY Selection power allocation THROUGHPUT Maxi-mum Ratio Combining Cognitive Radio Systems
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Research on the low complexity adaptive power allocation algorithm in cooperative systems 被引量:1
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作者 WANG Liang XIE Wei-hao +1 位作者 CHEN Hui-min WU Zhuo 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2010年第4期13-17,共5页
Cooperative diversity is a new technology to improve bit error rate (BER) performance in wireless communications, A new power allocation algorithm to improve BER performance in cellular uplink has been proposed in t... Cooperative diversity is a new technology to improve bit error rate (BER) performance in wireless communications, A new power allocation algorithm to improve BER performance in cellular uplink has been proposed in this paper. Some existing power allocation schemes were proposed for the purpose of maximizing the channel capacity or minimizing the outage probability. Different from these schemes, the proposed algorithm aims at minimizing the BER of the systems under the constraint of total transmission power. Besides this characteristic, the proposed algorithm can realize a low complexity real-time power allocation according to the fluctuation of channels. Simulation results show that the proposed algorithm can decrease the BER performance of the systems effectively. 展开更多
关键词 cooperative communication power allocation ber
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Joint power allocation and multi-relay selection scheme based on system outage probability 被引量:1
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作者 ZHOU Zhi-kang ZHU Qi 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2014年第5期9-16,23,共9页
An amplify-and-forward (AF) based multi-relay network is studied. In order to minimize the system outage probability with a required transmission rate, a joint power allocation (PA) and multi-relay selection schem... An amplify-and-forward (AF) based multi-relay network is studied. In order to minimize the system outage probability with a required transmission rate, a joint power allocation (PA) and multi-relay selection scheme is proposed under both total and individual power constraints (TIPC). In the proposed scheme, the idea of ordering is adopted to avoid exhaustive search without losing much system performance. Besides the channel quantity, the ordering algorithm proposed in this article also takes relays' maximal output ability into consideration, which is usually ignored in traditional relay ordering algorithms. In addition, simple power reallocation method is provided to avoid repetitive PA operation during the process of searching all possible relay subsets. By Adopting the idea of ordering and using the proposed power reallocation method lead to remarkable decrease of the computation complexity, making the scheme easier and more feasible to implement in practical communication scenarios. Simulations show that the proposed multi-relay selection scheme provides similar performance compared to the optimal scheme with optimal PA and exhaustive search (OPAES) but with much lower complexity. 展开更多
关键词 cooperative communication multi-relay selection power allocation outage probability AMPLIFY-AND-FORWARD
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Power auction and allocation for network-coded cooperation
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作者 徐虹完 邹君妮 《Journal of Shanghai University(English Edition)》 CAS 2011年第1期69-74,共6页
Optimal resource allocation is critical to the efficiency of cooperative communiCations. In this paper, we develop an auction-based power allocation mechanism for network-coded cooperation in wireless networks, in whi... Optimal resource allocation is critical to the efficiency of cooperative communiCations. In this paper, we develop an auction-based power allocation mechanism for network-coded cooperation in wireless networks, in which the sources compete for the relay power for maximum utility, while the relay node assigns the resource in accordance with the bids from the sources. Moreover, to improve the resource utilization, the relay node is allowed to perform network coding across the received information for the same destination. Finally, numerical results validate the performance of the proposed algorithm, and show that there exists a tradeoff between the system outage probability and the power consumed at the relay node. 展开更多
关键词 cooperative communication power auction resource allocation network coding
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Joint adaptive power allocation and interference suppression algorithms based on the MSER criterion for wireless sensor networks
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作者 Gui-jie WANG Yun-long CAI +1 位作者 Min-jian ZHAO Jie ZHONG 《Journal of Zhejiang University-Science C(Computers and Electronics)》 SCIE EI 2014年第10期917-928,共12页
In this study, a two-hop wireless sensor network with multiple relay nodes is considered where the amplify-and-forward(AF) scheme is employed. Two algorithms are presented to jointly consider interference suppression ... In this study, a two-hop wireless sensor network with multiple relay nodes is considered where the amplify-and-forward(AF) scheme is employed. Two algorithms are presented to jointly consider interference suppression and power allocation(PA) based on the minimization of the symbol error rate(SER) criterion. A stochastic gradient(SG) algorithm is developed on the basis of the minimum-SER(MSER) criterion to jointly update the parameter vectors that allocate the power levels among the relay sensors subject to a total power constraint and the linear receiver. In addition, a conjugate gradient(CG) algorithm is developed on the basis of the SER criterion. A centralized algorithm is designed at the fusion center. Destination nodes transmit the quantized information of the PA vector to the relay nodes through a limited-feedback channel. The complexity and convergence analysis of the proposed algorithms are carried out. Simulation results show that the proposed two adaptive algorithms significantly outperform the other previously reported algorithms. 展开更多
关键词 cooperative communications Adaptive filtering Symbol error rate(SER) Interference suppression power allocation
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Radio resource management in energy harvesting cooperative cognitive UAV assisted IoT networks:A multi-objective approach
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作者 Muhammad Rashid Ramzan Muhammad Naeem +2 位作者 Omer Chughtai Waleed Ejaz Mohammad Altaf 《Digital Communications and Networks》 SCIE CSCD 2024年第4期1088-1102,共15页
Cooperative communication through energy harvested relays in Cognitive Internet of Things(CIoT)has been envisioned as a promising solution to support massive connectivity of Cognitive Radio(CR)based IoT devices and to... Cooperative communication through energy harvested relays in Cognitive Internet of Things(CIoT)has been envisioned as a promising solution to support massive connectivity of Cognitive Radio(CR)based IoT devices and to achieve maximal energy and spectral efficiency in upcoming wireless systems.In this work,a cooperative CIoT system is contemplated,in which a source acts as a satellite,communicating with multiple CIoT devices over numerous relays.Unmanned Aerial Vehicles(UAVs)are used as relays,which are equipped with onboard Energy Harvesting(EH)facility.We adopted a Power Splitting(PS)method for EH at relays,which are harvested from the Radio frequency(RF)signals.In conjunction with this,the Decode and Forward(DF)relaying strategy is used at UAV relays to transmit the messages from the satellite source to the CIoT devices.We developed a Multi-Objective Optimization(MOO)framework for joint optimization of source power allocation,CIoT device selection,UAV relay assignment,and PS ratio determination.We formulated three objectives:maximizing the sum rate and the number of admitted CIoT in the network and minimizing the carbon dioxide emission.The MOO formulation is a Mixed-Integer Non-Linear Programming(MINLP)problem,which is challenging to solve.To address the joint optimization problem for an epsilon optimal solution,an Outer Approximation Algorithm(OAA)is proposed with reduced complexity.The simulation results show that the proposed OAA is superior in terms of CIoT device selection and network utility maximization when compared to those obtained using the Nonlinear Optimization with Mesh Adaptive Direct-search(NOMAD)algorithm. 展开更多
关键词 cooperative communication Energy harvesting power splitting Unmanned aerial vehicles Cognitive radio Internet of things Multi-objective optimization Relay assignment power allocation
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Resource allocation for cooperative diversity systems based on quadrature modulation 被引量:1
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作者 Jing Li Jianhua Ge +1 位作者 Yong Wang Ming Gao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第2期327-333,共7页
To improve the error performance and the resource utilization of cooperative systems, the optimum resource allocation, i.e., power allocation and partner choice, for an adaptive decode-and-forward (DF) cooperative d... To improve the error performance and the resource utilization of cooperative systems, the optimum resource allocation, i.e., power allocation and partner choice, for an adaptive decode-and-forward (DF) cooperative diversity system based on quadrature modulation is investigated. The closed-form expression of the bit error rate (BER) system performance is derived and an optimal power allocation (OPA) algorithm is proposed to optimize the power allocation between the local and relayed signals under the minimum BER criterion. Based on the OPA algorithm, a partner choice strategy is proposed to determine the partner locations specified by various cooperation gains. Simulation results show that the proposed resource optimization algorithms are superior to the unoptimized algorithms by significantly reducing the BER and improving the cooperative gain, which is useful to simplify the practical partner choice process. 展开更多
关键词 wireless communication cooperative diversity bit error rate ber resource allocation.
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Power Allocation in Primary User-Assisted Multi-Channel Cognitive Radio Networks
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作者 Qiong Wu Junni Zou Kangning Zhu 《Communications and Network》 2013年第3期238-244,共7页
This paper addresses power allocation problem for spectrum sharing multi-band cognitive radio networks, where the primary user (PU) allows secondary users (SUs) to transmit simultaneously with it by coding SU's si... This paper addresses power allocation problem for spectrum sharing multi-band cognitive radio networks, where the primary user (PU) allows secondary users (SUs) to transmit simultaneously with it by coding SU's signal together with its own signal. The PU acts as the relay for the SUs and sells its transmit power to the SUs to increase its benefit, and the SUs bid for the PU's transmit power for maximizing their utilities. We propose a power allocation scheme based on traditional ascending clock auction, in which the SUs iteratively submit the optimal power demand to the PU according to the PU's announced price, and the PU updates that price based on all SUs' total power demands. Then we mathematically prove the convergence property of the proposed auction algorithm (i.e., the auction algorithm converges in a finite number of clocks), and show that the proposed power auction algorithm can maximize the social welfare. Finally, the performance of the proposed scheme is verified by the simulation results. 展开更多
关键词 power allocation COGNITIVE Radio AUCTION cooperative communications
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Outage Probability Analysis for Modified Decode-and-Forward Model over Nakagami-m Fading Channels
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作者 啜钢 邹钰寒 刘振兴 《China Communications》 SCIE CSCD 2011年第3期145-153,共9页
This paper proposes a modified decodeand-forward(DAF) protocol with a three-node model,which contains two users and one destination.Each user can be either the source or the relay in different frames.We analyze the fo... This paper proposes a modified decodeand-forward(DAF) protocol with a three-node model,which contains two users and one destination.Each user can be either the source or the relay in different frames.We analyze the four cooperative cases in the first frame and run simulations to obtain the optimal power allocation coefficients in the second frame.The closed-form expression of outage probability is derived over Nakagami-m fading channels.Furthermore,we show that the proposed model has better performance than the non-cooperation system and traditional DAF strategy based on the derived outage probability. 展开更多
关键词 cooperative communication decodeand-forward Nakagami-m fading channel outage probability optimal power allocation
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无线再生中继网络的功率优化分配 被引量:2
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作者 陈实 陈雁 仇佩亮 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2006年第8期1297-1299,1305,共4页
针对中继传输中系统性能与发送端和中继器发射功率均有关的问题,提出了一种在总功率一定的条件下,以误码率最小为准则,优化分配发送端和中继器发射功率的方法.对于两跳中继(无分集)和合作分集两种再生中继网络,以大信噪比时的误码率上... 针对中继传输中系统性能与发送端和中继器发射功率均有关的问题,提出了一种在总功率一定的条件下,以误码率最小为准则,优化分配发送端和中继器发射功率的方法.对于两跳中继(无分集)和合作分集两种再生中继网络,以大信噪比时的误码率上界表达式为目标函数,通过Lagrange乘数法求得发送端和中继器功率优化分配的数值解.仿真结果表明,与发送端和中继器均匀分配功率相比,经功率优化分配后的中继网络,在误码率下降的同时,中断概率和信道容量的性能也得到提升. 展开更多
关键词 再生中继 误码率 功率优化分配 合作分集
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Joint Resource Allocation for Lifetime-aware Cooperative Multi-carrier DF System
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作者 Chao-Ping Guo Kun Han +1 位作者 Xiao-Long Zhang Hai-Lin Zhang 《International Journal of Automation and computing》 EI CSCD 2014年第1期87-92,共6页
In this paper,we study the problem of optimal resource allocation for lifetime maximization in an orthogonal-frequencydivision multiplexing(OFDM)system with decode-and-forward relay.The goal is to minimize total energ... In this paper,we study the problem of optimal resource allocation for lifetime maximization in an orthogonal-frequencydivision multiplexing(OFDM)system with decode-and-forward relay.The goal is to minimize total energy cost of the system by jointly optimizing power allocation,subcarrier pairing and relay selection.We present a heuristic solution that is composed of two parts.The first part is an optimal power allocation approach to allocate power to a subcarrier pair of the source and the relay.The second part is a modified Hungarian algorithm to make subcarrier pairing and relay selection.Evaluations show that the presented scheme outperforms other schemes in the total transmitted data and the network lifetime. 展开更多
关键词 cooperative communications resource allocation DECODE-AND-FORWARD orthogonal-frequency-division multiplexing(OFDM) subcarrier pairing power allocation relay selection
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Low-complexity distributed differential spacetime coding scheme for amplify-and-forward cooperative networks 被引量:2
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作者 YU XiangBin1,2, BI GuangGuo3 & XU WeiYe4 1 College of Information Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China 2 Department of Electronic Engineering, City University of Hong Kong, Hong Kong, China +1 位作者 3 National Mobile Communications Research Laboratory, Southeast University, Nanjing 210096, China 4 Department of Communication Engineering, Nanjing Institute of Technology, Nanjing 211167, China 《Science in China(Series F)》 2009年第8期1418-1427,共10页
By introducing a space-time coding scheme based on amicable orthogonality, we develop a distributed differential space-time coding scheme with the amplify-and-forward (AF) method for wireless cooperative networks. T... By introducing a space-time coding scheme based on amicable orthogonality, we develop a distributed differential space-time coding scheme with the amplify-and-forward (AF) method for wireless cooperative networks. The scheme requires no knowledge of the channel state information at both transmitters and receivers, and effectively decreases the realization complexity due to no channel estimation. Moreover, it has lower decoding complexity and higher coding advantage than the existing scheme, thus avoiding the shortcoming of exponential decoding complexity of some existing schemes. According to the pairwise error probability (PEP) analysis of the system, the power allocations of source and relay terminals are jointly optimized, and as a result, the PEP is minimized, which will provide a helpful guideline for system design. Numerical calculation and simulation results show that the developed scheme is superior to the existing scheme. Moreover, the scheme with optimal power allocation yields obvious performance improvement over that with equal power allocation. 展开更多
关键词 differential space-time coding cooperative communication amplify-and-forward method power allocation
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