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Stackelberg Game for Wireless Powered and Backscattering Enabled Sensor Networks
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作者 Lyu Bin Cao Yi +2 位作者 Wang Shuai Guo Haiyan Hao Chengyao 《China Communications》 SCIE CSCD 2024年第3期189-204,共16页
This paper investigates a wireless powered and backscattering enabled sensor network based on the non-linear energy harvesting model, where the power beacon(PB) delivers energy signals to wireless sensors to enable th... This paper investigates a wireless powered and backscattering enabled sensor network based on the non-linear energy harvesting model, where the power beacon(PB) delivers energy signals to wireless sensors to enable their passive backscattering and active transmission to the access point(AP). We propose an efficient time scheduling scheme for network performance enhancement, based on which each sensor can always harvest energy from the PB over the entire block except its time slots allocated for passive and active information delivery. Considering the PB and wireless sensors are from two selfish service providers, we use the Stackelberg game to model the energy interaction among them. To address the non-convexity of the leader-level problem, we propose to decompose the original problem into two subproblems and solve them iteratively in an alternating manner. Specifically, the successive convex approximation, semi-definite relaxation(SDR) and variable substitution techniques are applied to find a nearoptimal solution. To evaluate the performance loss caused by the interaction between two providers, we further investigate the social welfare maximization problem. Numerical results demonstrate that compared to the benchmark schemes, the proposed scheme can achieve up to 35.4% and 38.7% utility gain for the leader and the follower, respectively. 展开更多
关键词 backscatter communication energy interaction stackelberg game wireless powered sensor network
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Enabling Efficient Data Transmission in Wireless Sensor Networks-Based IoT Application
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作者 Ibraheem Al-Hejri Farag Azzedin +1 位作者 Sultan Almuhammadi Naeem Firdous Syed 《Computers, Materials & Continua》 SCIE EI 2024年第6期4197-4218,共22页
The use of the Internet of Things(IoT)is expanding at an unprecedented scale in many critical applications due to the ability to interconnect and utilize a plethora of wide range of devices.In critical infrastructure ... The use of the Internet of Things(IoT)is expanding at an unprecedented scale in many critical applications due to the ability to interconnect and utilize a plethora of wide range of devices.In critical infrastructure domains like oil and gas supply,intelligent transportation,power grids,and autonomous agriculture,it is essential to guarantee the confidentiality,integrity,and authenticity of data collected and exchanged.However,the limited resources coupled with the heterogeneity of IoT devices make it inefficient or sometimes infeasible to achieve secure data transmission using traditional cryptographic techniques.Consequently,designing a lightweight secure data transmission scheme is becoming essential.In this article,we propose lightweight secure data transmission(LSDT)scheme for IoT environments.LSDT consists of three phases and utilizes an effective combination of symmetric keys and the Elliptic Curve Menezes-Qu-Vanstone asymmetric key agreement protocol.We design the simulation environment and experiments to evaluate the performance of the LSDT scheme in terms of communication and computation costs.Security and performance analysis indicates that the LSDT scheme is secure,suitable for IoT applications,and performs better in comparison to other related security schemes. 展开更多
关键词 IoT LIGHTWEIGHT computation complexity communication overhead cybersecurity threats threat prevention secure data transmission Wireless Sensor networks(WSNs) elliptic curve cryptography
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Distributed robust power control in two-tier vehicle networks under uncertain channel environments
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作者 Zhixin Liu Jiawei Su +3 位作者 Yuan-ai Xie Yazhou Yuan Yi Yang Xinping Guan 《Digital Communications and Networks》 SCIE CSCD 2023年第3期734-742,共9页
This paper proposes a novel optimization scheme to support stable and reliable vehicle-to-everything connections in two-tier networks,where the uplink channel of the cellular user is reused by underlay vehicle-to-vehi... This paper proposes a novel optimization scheme to support stable and reliable vehicle-to-everything connections in two-tier networks,where the uplink channel of the cellular user is reused by underlay vehicle-to-vehicle communications.However,considering complex channel fading and high-speed vehicle movement,the cer-tainty assumption is impractical and fails to maintain power control strategy in reality in the traditional statical vehicular networks.Rather than the perfect channel state information assumption,the first-order Gauss-Markov process which is a probabilistic model affected by vehicle speed and fading is introduced to describe imperfect channel gains.Moreover,interference management is a major challenge in reusing communications,especially in uncertain channel environments.Power control is an effective way to realize interference management,and optimal power allocation can ensure that interference of the user meets the communication requirements.In this study,the sum-rate-oriented power control scheme and minimum-rate-oriented power control scheme were implemented to manage interference and satisfy different design objectives.Since both of these schemes are non-convex and intractable,the Bernstein approximation and successive convex approximation methods were adopted to transform the original problems into convex ones.Furthermore,a novel distributed robust power control al-gorithm was developed to determine the optimal solutions.The performance of the algorithm was evaluated through numerical simulations,and the results indicate that the proposed algorithm is effective in vehicular communication networks with uncertain channel environments. 展开更多
关键词 Vehicle-to-Everything communications Vehicular two-tier networks Channel uncertainty power control
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Covert Communication in Integrated High Altitude Platform Station Terrestrial Networks
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作者 Zeke Wu Kefeng Guo +1 位作者 Rui Liu Shibin Zhu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期583-598,共16页
In recent years,Internet of Things(IoT)technology has emerged and gradually sprung up.As the needs of largescale IoT applications cannot be satisfied by the fifth generation(5G)network,wireless communication network n... In recent years,Internet of Things(IoT)technology has emerged and gradually sprung up.As the needs of largescale IoT applications cannot be satisfied by the fifth generation(5G)network,wireless communication network needs to be developed into the sixth generation(6G)network.However,with the increasingly prominent security problems of wireless communication networks such as 6G,covert communication has been recognized as one of the most promising solutions.Covert communication can realize the transmission of hidden information between both sides of communication to a certain extent,which makes the transmission content and transmission behavior challenging to be detected by noncooperative eavesdroppers.In addition,the integrated high altitude platform station(HAPS)terrestrial network is considered a promising development direction because of its flexibility and scalability.Based on the above facts,this article investigates the covert communication in an integrated HAPS terrestrial network,where a constant power auxiliary node is utilized to send artificial noise(AN)to realize the covert communication.Specifically,the covert constraint relationship between the transmitting and auxiliary nodes is derived.Moreover,the closed-form expressions of outage probability(OP)and effective covert communication rate are obtained.Finally,numerical results are provided to verify our analysis and reveal the impacts of critical parameters on the system performance. 展开更多
关键词 Covert communication the integrated HAPS terrestrial network constant power auxiliary node artificial noise(AN) effective covert communication rate
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Data Aggregation-based Transmission Method in Ultra-Dense Wireless Networks
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作者 Dae-Young Kim Seokhoon Kim 《Intelligent Automation & Soft Computing》 SCIE 2023年第1期727-737,共11页
As the Internet of Things(IoT)advances,machine-type devices are densely deployed and massive networks such as ultra-dense networks(UDNs)are formed.Various devices attend to the network to transmit data using machine-t... As the Internet of Things(IoT)advances,machine-type devices are densely deployed and massive networks such as ultra-dense networks(UDNs)are formed.Various devices attend to the network to transmit data using machine-type communication(MTC),whereby numerous,various are generated.MTC devices generally have resource constraints and use wireless communication.In this kind of network,data aggregation is a key function to provide transmission efficiency.It can reduce the number of transmitted data in the network,and this leads to energy saving and reducing transmission delays.In order to effectively operate data aggregation in UDNs,it is important to select an aggregation point well.The total number of transmitted data may vary,depending on the aggregation point to which the data are delivered.Therefore,in this paper,we propose a novel data aggregation scheme to select the appropriate aggregation point and describe the data transmission method applying the proposed aggregation scheme.In addition,we evaluate the proposed scheme with extensive computer simulations.Better performances in the proposed scheme are achieved compared to the conventional approach. 展开更多
关键词 Data aggregation data transmission ultra-dense network machine-type communication Internet of Things
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Load Balancing-Based Routing Optimization Mechanism for Power Communication Networks 被引量:12
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作者 Ningzhe Xing Siya Xu +1 位作者 Sidong Zhang Shaoyong Guo 《China Communications》 SCIE CSCD 2016年第8期169-176,共8页
In power communication networks, it is a challenge to decrease the risk of different services efficiently to improve operation reliability. One of the important factor in reflecting communication risk is service route... In power communication networks, it is a challenge to decrease the risk of different services efficiently to improve operation reliability. One of the important factor in reflecting communication risk is service route distribution. However, existing routing algorithms do not take into account the degree of importance of services, thereby leading to load unbalancing and increasing the risks of services and networks. A routing optimization mechanism based on load balancing for power communication networks is proposed to address the abovementioned problems. First, the mechanism constructs an evaluation model to evaluate the service and network risk degree using combination of devices, service load, and service characteristics. Second, service weights are determined with modified relative entropy TOPSIS method, and a balanced service routing determination algorithm is proposed. Results of simulations on practical network topology show that the mechanism can optimize the network risk degree and load balancing degree efficiently. 展开更多
关键词 power communication networks load balancing routing optimization
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Power Line Monitoring Data Transmission Using Wireless Sensor Network 被引量:4
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作者 Lifen Li Huaiyu Zhao 《Journal of Power and Energy Engineering》 2015年第8期83-88,共6页
The WSN used in power line monitoring is long chain structure, and the bottleneck near the Sink node is more obvious. In view of this, A Sink nodes’ cooperation mechanism is presented. The Sink nodes from different W... The WSN used in power line monitoring is long chain structure, and the bottleneck near the Sink node is more obvious. In view of this, A Sink nodes’ cooperation mechanism is presented. The Sink nodes from different WSNs are adjacently deployed. Adopting multimode and spatial multiplexing network technology, the network is constructed into multi-mode-level to achieve different levels of data streaming. The network loads are shunted and the network resources are rationally utilized. Through the multi-sink nodes cooperation, the bottlenecks at the Sink node and its near several jump nodes are solved and process the competition of communication between nodes by channel adjustment. Finally, the paper analyzed the method and provided simulation experiment results. Simulation results show that the method can solve the funnel effect of the sink node, and get a good QoS. 展开更多
关键词 WIRELESS Sensor network (WSN) power Line Monitoring Data transmission MULTIMODE network
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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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Spatial-Modulated Physical-Layer Network Coding Based on Block Markov Superposition Transmission for Maritime Relay Communications 被引量:1
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作者 Yao Shi Liming Zheng +1 位作者 Wenchao Lin Xiao Ma 《China Communications》 SCIE CSCD 2020年第3期26-35,共10页
As an alternative to satellite communications,multi-hop relay networks can be deployed for maritime long-distance communications.Distinct from terrestrial environment,marine radio signals are affected by many factors,... As an alternative to satellite communications,multi-hop relay networks can be deployed for maritime long-distance communications.Distinct from terrestrial environment,marine radio signals are affected by many factors,e.g.,weather conditions,evaporation ducting,and ship rocking caused by waves.To ensure the data transmission reliability,the block Markov superposition transmission(BMST)codes,which are easily configurable and have predictable performance,are applied in this study.Meanwhile,the physical-layer network coding(PNC)scheme with spatial modulation(SM)is adopted to improve the spectrum utilization.For the BMST-SMPNC system,we propose an iterative algorithm,which utilizes the channel observations and the a priori information from BMST decoder,to compute the soft information corresponding to the XORed bits constructed by the relay node.The results indicate that the proposed scheme outperforms the convolutional coded SM-PNC over fast-fading Rician channels.Especially,the performance can be easily improved in high spatial correlation maritime channel by increasing the memory m. 展开更多
关键词 block Markov superposition transmission maritime relay communications physical-layer network coding Rician fading spatial modulation
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Discussion on the Integrated Communication System of Local Electric Power Network in China
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作者 Zhang Guanyuan Gao Yun (Communication Department of Nanjing Automation Research Institute) 《Electricity》 1998年第4期50-53,共4页
This paper describes current situation and special requirements of local electric power communication network in China. The paper discusses the disadvantages of SDH and fiber loop carrier system applied to electric po... This paper describes current situation and special requirements of local electric power communication network in China. The paper discusses the disadvantages of SDH and fiber loop carrier system applied to electric power communication network. It presents a new Communication System-IDS-2000 integrated digital communication system. The paper introduces the characteristics and application of IDS-2000 system in the local electric power communication network. 展开更多
关键词 DEDICATED electric power communication network optical fiber communication SDH intelligent PCM TERMINAL UNIFORM network management systems
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Application of Network Information Communication Technology in Power System
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作者 Chuanpeng Liu 《Journal of Electronic Research and Application》 2018年第6期1-4,共4页
Network information communication technology in power systems is the key to ensuring the safe and efficient operation of power grids.The network information communication technology itself has advantages in automation... Network information communication technology in power systems is the key to ensuring the safe and efficient operation of power grids.The network information communication technology itself has advantages in automation operation and information transmission,thus is widely applied to the power system.In the case of ensuring that the power system is compatible with the network information communication technology,the control of the power system can be strengthened,and the operational efficiency of the power system can be improved.This paper mainly analyzes the specific application of network information communication technology in power system. 展开更多
关键词 power system network INFORMATION communication technology APPLICATION
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Power Line Communications Networking Method Based on Hybrid Ant Colony and Genetic Algorithm
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作者 Qianghui Xiao Huan Jin Xueyi Zhang 《Engineering(科研)》 2020年第8期581-590,共10页
When solving the routing problem with traditional ant colony algorithm, there is scarce in initialize pheromone and a slow convergence and stagnation for the complex network topology and the time-varying characteristi... When solving the routing problem with traditional ant colony algorithm, there is scarce in initialize pheromone and a slow convergence and stagnation for the complex network topology and the time-varying characteristics of channel in power line carrier communication of low voltage distribution grid. The algorithm is easy to fall into premature and local optimization. Proposed an automatic network algorithm based on improved transmission delay and the load factor as the evaluation factors. With the requirements of QoS, a logical topology of power line communication network is established. By the experiment of MATLAB simulation, verify that the improved Dynamic hybrid ant colony genetic algorithm (DH_ACGA) algorithm has improved the communication performance, which solved the QoS routing problems of power communication to some extent. 展开更多
关键词 power Line Carrier communication network Quality of Service Hybrid Ant Colony and Genetic Algorithm
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Design of Power Communication Data Network Management System and Implementation of Data Acquisition Module
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作者 Yue Zhang Zefeng Jian Hao Wang 《Journal of Electronic Research and Application》 2021年第6期1-5,共5页
The power communication network is a separate network from the power grid whose primary purpose is to ensure the power grid's safe operation.This paper expounds the composition of the comprehensive network managem... The power communication network is a separate network from the power grid whose primary purpose is to ensure the power grid's safe operation.This paper expounds the composition of the comprehensive network management architecture of the power communication data network and the implementation of the data acquisition module in the network management system through theoretical analysis,for the reference of relevant personnel,in order to better promote the collection of power grid communication network data. 展开更多
关键词 Electric power communication network management system design Data acquisition
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Research on reliability index of a large communication network with domain partition and interconnection 被引量:2
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作者 Dai Fusheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第3期666-674,共9页
In order to indicate the performances of a large-scale communication network with domain partition and interconnection today, a kind of reliability index weighed by normalized capacity is defined. Based on the route r... In order to indicate the performances of a large-scale communication network with domain partition and interconnection today, a kind of reliability index weighed by normalized capacity is defined. Based on the route rules of network with domain partition and interconnection, the interconnection indexes among the nodes within the domain and among the domains are given from several aspects. It is expatiated on that the index can thoroughly represent the effect on the reliability index of the objective factor and the subjective measures of the designer, which obeys the route rules of a network with domain partition and interconnection. It is discussed that the defined index is rational and compatible with the traditional index. 展开更多
关键词 communication network RELIABILITY interconnection network with domain partition transmission capacity
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Create Your Own Data and Energy Integrated Communication Network:A Brief Tutorial and a Prototype System 被引量:2
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作者 Yali Zheng Yitian Zhang +2 位作者 Yang Wang Jie Hu Kun Yang 《China Communications》 SCIE CSCD 2020年第9期193-209,共17页
In order to satisfy the ever-increasing energy appetite of the massive battery-powered and batteryless communication devices,radio frequency(RF)signals have been relied upon for transferring wireless power to them.The... In order to satisfy the ever-increasing energy appetite of the massive battery-powered and batteryless communication devices,radio frequency(RF)signals have been relied upon for transferring wireless power to them.The joint coordination of wireless power transfer(WPT)and wireless information transfer(WIT)yields simultaneous wireless information and power transfer(SWIPT)as well as data and energy integrated communication network(DEIN).However,as a promising technique,few efforts are invested in the hardware implementation of DEIN.In order to make DEIN a reality,this paper focuses on hardware implementation of a DEIN.It firstly provides a brief tutorial on SWIPT,while summarising the latest hardware design of WPT transceiver and the existing commercial solutions.Then,a prototype design in DEIN with full protocol stack is elaborated,followed by its performance evaluation. 展开更多
关键词 data and energy integrated communication network(DEIN) wireless power transfer(WPT) simultaneously wireless information and power transfer(SWIPT) RF charging hardware implementation
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Hybrid Satellite-UAV-Terrestrial Maritime Networks:Network Selection for Users on A Vessel Optimized with Transmit Power and UAV Position 被引量:1
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作者 Xiangling Li Wenjing Shi 《China Communications》 SCIE CSCD 2022年第9期37-46,共10页
The hybrid satellite-UAV-terrestrial maritime networks have shown great promise for broadband coverage at sea.The existing works focused on vessels collaboratively served by UAV-enabled aerial base station(ABSs)and te... The hybrid satellite-UAV-terrestrial maritime networks have shown great promise for broadband coverage at sea.The existing works focused on vessels collaboratively served by UAV-enabled aerial base station(ABSs)and terrestrial base stations(TBSs)deployed along the coast,and proved that data rate could be improved by optimizing transmit power and ABS’s position.In practice,users on a vessel can be collaboratively served by an ABS and a vesselenabled base station(VBS)in different networks.In this case,how to select the network for users on a vessel is still an open issue.In this paper,a TBS and a satellite respectively provide wireless backhaul for the ABS and the VBS.The network selection is jointly optimized with transmit power of ABS and VBS,and ABS’s position for improving data rate of all users.We solve it by finding candidates for network selection and iteratively solving transmit power and ABS’s position for each candidate.Simulation results demonstrate that data rate can be improved by collaborative coverage for users on a vessel. 展开更多
关键词 maritime communications satellite-UAV-terrestrial network network selection power allocation
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Reliability index algorithm of a sub-domain interconnection large communication network 被引量:1
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作者 Fusheng Dai Aijun Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第2期339-348,共10页
The normalized weighted capacity reliability index of a sub-domain interconnection large scale communication network is defined and a new algorithm to calculate the reliability index is proposed, The proposed algorith... The normalized weighted capacity reliability index of a sub-domain interconnection large scale communication network is defined and a new algorithm to calculate the reliability index is proposed, The proposed algorithm can be performed using logical or algebraic operation by means of computer-aided programming and the correctness of each key step is validated in detail. This paper takes the sub-domain interconnection symmetrical topologi- cal network for a typical example to calculate the network reliability index and verifies the correctness of the proposed algorithm us- ing the real measured statistical data. The real measured results are well in accordance with the results obtained by the proposed algorithm. The result shows that the proposed algorithm is a valid means to estimate the reliability index of a sub-domain intercon- nection large-scale communication network. 展开更多
关键词 communication network reliability sub-domain inter- connection transmission capacity.
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Minimum Load-curtailment in Transmission Network Planning Considering Integrated Wind Farms 被引量:14
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作者 CHEN Yan WEN Jinyu CHENG Shijie 《中国电机工程学报》 EI CSCD 北大核心 2011年第34期I0003-I0003,5,共1页
提出应用鲁棒线性优化理论来研究电网规划中含多个风电场的最小切负荷量计算问题,为含多个风电场的系统安全性研究提供了一条新的思路。根据Seng-Cheol Kang提出的鲁棒线性优化理论,建立电网规划中考虑风电场影响的最小切负荷量模型。... 提出应用鲁棒线性优化理论来研究电网规划中含多个风电场的最小切负荷量计算问题,为含多个风电场的系统安全性研究提供了一条新的思路。根据Seng-Cheol Kang提出的鲁棒线性优化理论,建立电网规划中考虑风电场影响的最小切负荷量模型。该模型以出力上下限和出力期望值来描述风电场的出力,最终转化为一确定性的线性规划问题并进行求解。在计及或不计及发电机调整的情况下,该模型均能够给出最安全的切负荷方案,除此以外还能给出更多介于最可靠与最经济之间的切负荷方案,实现灵活决策;在计及发电机出力可调的情况下,该模型能够给出相应的发电机出力方案;该模型能够初步给出各种切负荷方案下电网规划方案的可靠程度。基于修正的Garver’s 6节点系统和修正的巴西南部46节点系统算例测试结果验证了该方法的有效性。 展开更多
关键词 英文摘要 内容介绍 编辑工作 期刊
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QoS-Aware Power Allocation Scheme for Relay Satellite Networks 被引量:1
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作者 Jin’ao Yu Xiaogang Tang +3 位作者 Shibing Zhu Haopeng Sun Lunxin Zhong Guangyu Yang 《Journal of Beijing Institute of Technology》 EI CAS 2021年第1期82-90,共9页
This paper investigated a QoS-aware power allocation for relay satellite networks.For the given QoS requirements,we analyzed the signal model of relay transmission and formulated the power minimization problem which i... This paper investigated a QoS-aware power allocation for relay satellite networks.For the given QoS requirements,we analyzed the signal model of relay transmission and formulated the power minimization problem which is non-convex and difficult to solve.To find the optimal solution to the considered problem,we first analyzed the optimization problem and equivalently turn it into a convex optimization problem.Then,we provided a Lagrangian dual-based method to obtain the closed-form of the power allocation and provided an iterative algorithm to the optimal solution.Moreover,we also extended the results to the cooperative transmission mode.Finally,simulation results were provided to verify the superiority of the proposed algorithm. 展开更多
关键词 power allocation relay satellite network quality of service cooperative transmission
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A New Method to Improve Performance of Cooperative Underwater Acoustic Wireless Sensor Networks via Frequency Controlled Transmission Based on Length of Data Links 被引量:1
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作者 Vahid Tabataba Vakily Mohammadjavad Jannati 《Wireless Sensor Network》 2010年第5期381-389,共9页
In this paper a new method to improve performance of cooperative underwater acoustic (UWA) sensor networks will be introduced. The method is based on controlling and optimizing carrier frequencies which are used in da... In this paper a new method to improve performance of cooperative underwater acoustic (UWA) sensor networks will be introduced. The method is based on controlling and optimizing carrier frequencies which are used in data links between network nods. In UWA channels Pathloss and noise power spectrum density (psd) are related to carrier frequency. Therefore, unlike radio communications, in UWA Communications signal to noise ratio (SNR) is related to frequency besides propagation link length. In such channels an optimum frequency in whole frequency band and link lengths cannot be found. In Cooperative transmission, transmitter sends one copy of transmitted data packets to relay node. Then relay depending on cooperation scheme, amplifies or decodes each data packet and retransmit it to destination. Receiver uses and combines both received signals to estimate transmitted data. This paper wants to propose a new method to decrease network power consumptions by controlling and sub-optimizing transmission frequency based on link length. For this purpose, underwater channel parameters is simulated and analyzed in 1km to 10km lengths (midrange channel). Then link lengths sub categorized and in each category, optimum frequency is computed. With these sub optimum frequencies, sensors and base station can adaptively control their carrier frequencies based on link length and decrease network’s power consumptions. Finally Different Cooperative transmission schemes “Decode and Forward (DF)” and “Amplify and Forward (AF)”, are simulated in UWA wireless Sensor network with and without the new method. In receiver maximum ratio combiner (MRC) is used to combining received signals and making data estimations. Simulations show that the new method, called AFC cooperative UWA communication, can improve performance of underwater acoustic wireless sensor networks up to 40.14%. 展开更多
关键词 UNDERWATER Acoustic communicationS Wireless Sensor networks COOPERATIVE transmission Decode and FORWARD Amplify and FORWARD
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