With the acceleration of the intelligent transformation of power systems,the requirements for communication technology are increasingly stringent.The application of 5G mobile communication technology in power communic...With the acceleration of the intelligent transformation of power systems,the requirements for communication technology are increasingly stringent.The application of 5G mobile communication technology in power communication is analyzed.In this study,5G technology features,application principles,and practical strategies are discussed,and methods such as network slicing,customized deployment,edge computing collaborative application,communication equipment integration and upgrading,and multi-technology collaboration and complementation are proposed.It aims to effectively improve the efficiency,reliability,and security of power communication,solve the problem that traditional communication technology is difficult to meet the diversified needs of power business,and achieve the effect of optimizing the power communication network and supporting the intelligent development of the power system.展开更多
In generator design field,waveform total harmonic distortion(THD)and telephone harmonic factor(THF)are parameters commonly used to measure the impact of generator no-load voltage harmonics on the power communication q...In generator design field,waveform total harmonic distortion(THD)and telephone harmonic factor(THF)are parameters commonly used to measure the impact of generator no-load voltage harmonics on the power communication quality.Tubular hydrogenerators are considered the optimal generator for exploiting low-head,high-flow hydro resources,and they have seen increasingly widespread application in China's power systems recent years.However,owing to the compact and constrained internal space of such generators,their internal magnetic-field harmonics are pronounced.Therefore,accurate calculation of their THD and THF is crucial during the analysis and design stages to ensure the quality of power communication.Especially in the electromagnetic field finite element modeling analysis of such generators,the type and order of the finite element meshes may have a significant impact on the THD and THF calculation results,which warrants in-depth research.To address this,this study takes a real 34 MW large tubular hydrogenerator as an example,and establishes its electromagnetic field finite element model under no-load conditions.Two types of meshes,five mesh densities,and two mesh orders are analyzed to reveal the effect of electromagnetic field finite element mesh types and orders on the calculation results of THD and THF for such generators.展开更多
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
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
Couplets,as a vital symbol of Chinese traditional culture,hold prominent cultural significance in Beijing’s urban neighborhoods.This paper assesses the current state of cultural communication efficacy regarding coupl...Couplets,as a vital symbol of Chinese traditional culture,hold prominent cultural significance in Beijing’s urban neighborhoods.This paper assesses the current state of cultural communication efficacy regarding couplets in Beijing’s neighborhoods,identifying challenges including fragile cultural ecosystems,limitations of communication agents,homogeneity in content and forms,and outdated dissemination mechanisms.To address these issues,the study conducts an in-depth analysis of strategies to enhance the cultural dissemination capacity of Beijing’s neighborhood couplet culture,proposing comprehensive enhancement pathways.The research aims to effectively elevate the cultural influence of Beijing’s neighborhood couplet culture and facilitate the city’s development as a national cultural center.展开更多
The power communication network can be abstracted as a graph based on its topology. In this paper, we propose an approach to conduct simulations of power communication network based on its graph representation. In par...The power communication network can be abstracted as a graph based on its topology. In this paper, we propose an approach to conduct simulations of power communication network based on its graph representation. In particular, the nodes and edges in the graph refer to the ports and channels in the grid topology. Different applications on the grid can be transformed into queries over the graph. Hence, in this paper, we build our grid simulation model based on the Neo4 j graph database. We also propose a fault extension algorithm based on predicate calculus. Our experiment evaluations show that the proposed approach can effectively improve the efficiency of the power grid.展开更多
Power line communication(PLC)provides intelligent electrical functions such as power quality measurement,fault surveys,and remote control of electrical network.Most of research works have been done in low voltage(LV)s...Power line communication(PLC)provides intelligent electrical functions such as power quality measurement,fault surveys,and remote control of electrical network.Most of research works have been done in low voltage(LV)scenario due to the fast development of in-home PLC.The aim of this paper is to evaluate the link-level performance of a medium voltage(MV)MIMO-OFDM communication system based on transmission link under underground power line channel.The MIMO channel is modeled as a modified multipath model in the presence of impulsive noise and background noise.We first perform a measurement on the practical MV MIMO channel parameters for a section of buried cable of 1 km long in Ganzhou city,Jiangxi province,China.Based on the measured channel,we design the frame structure based on an IEEE standard for broadband over power line networks[1]to support MV MIMO-OFDM transmission.According to designed frame structure,we design an encoder and a decoder for a dual binary tail-biting turbo code and optimize some key decoder parameters for low bit error rate performance.Finally,the link-level performance for both spatial multiplexing and spatial diversity are evaluated.Numeral results show that MV MIMO-OFDM is a promising approach to provide both high data rate and link reliability for PLC.展开更多
In the past decade,several efforts around the world were started with the goal of introducing "smart metering" capabilities into the power grid.These efforts have spurred renewed interest in the design of ne...In the past decade,several efforts around the world were started with the goal of introducing "smart metering" capabilities into the power grid.These efforts have spurred renewed interest in the design of next generation Narrowband Power Line Communications(NB-PLC) transceivers.In the past few years,ITU-T and IEEE have standardized a family of next generation OFDM-based NB-PLC transceivers some of which are today being considered for massive deployments in Europe and Asia.This paper addresses the important role that PLC has not only for smart metering but also for many other Smart Grid applications,and also gives an overview of the main differences between these next generation NB-PLC standards.展开更多
Adaptive bit-loading is a key technology in high speed power line communications with the Orthogonal Frequency Division Multiplexing (OFDM) modulation technology. According to the real situation of the transmitting po...Adaptive bit-loading is a key technology in high speed power line communications with the Orthogonal Frequency Division Multiplexing (OFDM) modulation technology. According to the real situation of the transmitting power spectrum limited in high speed power line communications, this paper explored the adaptive bit loading algorithm to maximize transmission bit number when transmitting power spectral density and bit error rate are not exceed upper limit. With the characteristics of the power line channel, first of all, it obtains the optimal bit loading algorithm, and then provides the improved algorithm to reduce the computational complexity. Based on the analysis and simulation, it offers a non-iterative bit allocation algorithm, and finally the simulation shows that this new algorithm can greatly reduce the computational complexity, and the actual bit allocation results close to optimal.展开更多
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
Most existing media access control(MAC) protocols in power line communication(PLC) networks just discard the colliding data packets when collision occurs.The collision deteriorates throughput and delay performance of ...Most existing media access control(MAC) protocols in power line communication(PLC) networks just discard the colliding data packets when collision occurs.The collision deteriorates throughput and delay performance of system under high traffic conditions.This article presents a novel media access scheme with fast collision resolution for in-home power line networks.It works by first recognizing the colliding stations through detecting the inserted unique ID sequence ahead of data packets,then the source nodes retransmitting their packets immediately after the collision slot.The proposed protocol maintains the benefits of ALOHA systems.It needs no scheduling overhead and is suitable for bursty sources,such as multimedia data packets.Computer simulations have demonstrated that this approach can achieve high throughput due to its ability of resolving collisions.展开更多
This letter derives the Equivalent M-band Discrete Wavelet(EMDW) transmission mode of Orthogonal Frequency Division Multiplexing(OFDM) transmission systems, and presents a new Quadrature M-band Discrete Wavelet(QMDW) ...This letter derives the Equivalent M-band Discrete Wavelet(EMDW) transmission mode of Orthogonal Frequency Division Multiplexing(OFDM) transmission systems, and presents a new Quadrature M-band Discrete Wavelet(QMDW) based OFDM-CDMA(Code Division Multiple Access) communication systems for high speed Power Line Communication (PLC) channels.This system gives much better robustness to Inter-Channel Interference (ICI), Multi-User Interference (MUI) and noise interference, which is verified by simulation.展开更多
This paper presents the basic principle of OFDM technology and some key technologies, and do the simulation of OFDM technology. Secondly, on the basis of the design of intelligent Home Furnishing system demand, this p...This paper presents the basic principle of OFDM technology and some key technologies, and do the simulation of OFDM technology. Secondly, on the basis of the design of intelligent Home Furnishing system demand, this paper research and design low voltage power line carrier communication based on Intelligent Home Furnishing system for. The circuit takes ARM Cortex-M3 based on the ARM kernel as the central controller, and realize remote monitoring and control of equipment through the transplantation of uC/OS-II system and the design of Web Serve program. Using OFDM power line carrier communication modes as networking mode of the intelligent Home Furnishing system. Finally, the paper realize the intelligent node and relevant software that constitute a complete system of intelligent Home Furnishing.展开更多
A new mobile communications network architecture is proposed to solve four existing bottlenecks that restrict the rapid development of mobile communications,as well as to meet the development demands of future broadba...A new mobile communications network architecture is proposed to solve four existing bottlenecks that restrict the rapid development of mobile communications,as well as to meet the development demands of future broadband mobile communications. The architecture introduces the Information Lamp (IL),a novel device carrying out transceiver function,as the access point,besides providing light. It fulfills information interaction between the access points and radio access network through the power line (or fiber). The new system,supported by core technologies such as multi-antenna based distributed space-time signal processing and distributed radio resource management,integrates the wired and wireless networks to provide high-speed and high-quality mobile communication services.展开更多
Power line communication technology is used in various applications, from high voltage network to the low voltage network, as it is the only wired communication technology that is comparable with wireless communicatio...Power line communication technology is used in various applications, from high voltage network to the low voltage network, as it is the only wired communication technology that is comparable with wireless communication network. It works by injecting a modulated carrier wave into the electric cables from one transceiver to another. But still, the noise level and impedance mismatch are still the main concern of this technology, particularly in the low voltage network in residential area. Power line has additive non-white noise and extremely harsh environment for communication. At the same time, there is signal attenuation along the power line caused by the impedance mismatch in the power line network. Even though these problems can be controlled using a band-pass filter and an impedance matching circuit respectively, but the impedances in the power line are time and location variant and it is rather difficult to design a circuit that allows maximum power transfer in the system all the time. Thus in this paper, a new adaptive impedance matching circuits is proposed for narrowband power line communication. This methodology is derived based on the RLC band-pass filter circuit. This concept is designed to achieve simpler configuration and higher matching resolution.展开更多
Acknowledgments Thanks for assistance and support, which is provided by State Grid Corporation of China and State Grid Communication Information & Telecommunication Company, for the project in the process of researc...Acknowledgments Thanks for assistance and support, which is provided by State Grid Corporation of China and State Grid Communication Information & Telecommunication Company, for the project in the process of research and development. Fibrlink Communications Co., Ltd will keep exerting itself to innovating, which aims for making more contribution of the smart grid on energy reduction and environment protection.展开更多
The number and creativity of side channel attacks have increased dramatically in recent years. Of particular interest are attacks leveraging power line communication to 1) gather information on power consumption from ...The number and creativity of side channel attacks have increased dramatically in recent years. Of particular interest are attacks leveraging power line communication to 1) gather information on power consumption from the victim and 2) exfiltrate data from compromised machines. Attack strategies of this nature on the greater power grid and building infrastructure levels have been shown to be a serious threat. This project further explores this concept of a novel attack vector by creating a new type of penetration testing tool: an USB power adapter capable of remote monitoring of device power consumption and communicating through powerline communications.展开更多
The dissemination of Chinese culture to international students in China encompasses two closely interconnected dimensions:first,the dissemination aimed at international students to cultivate their understanding and re...The dissemination of Chinese culture to international students in China encompasses two closely interconnected dimensions:first,the dissemination aimed at international students to cultivate their understanding and recognition of the core values of Chinese culture;second,the dissemination of Chinese culture by international students themselves,which involves creating a diversified platform to effectively communicate China’s narratives.From the perspective of external cultural dissemination,this study employs a literature research method combined with CiteSpace knowledge mapping software to analyze and summarize the research network,hotspots,and knowledge structure within the field of international education in China.The exploration of future development directions presents significant practical value and contemporary relevance.展开更多
The main function of the power communication business is to monitor,control and manage the power communication network to ensure normal and stable operation of the power communication network.Commu-nication services r...The main function of the power communication business is to monitor,control and manage the power communication network to ensure normal and stable operation of the power communication network.Commu-nication services related to dispatching data networks and the transmission of fault information or feeder automation have high requirements for delay.If processing time is prolonged,a power business cascade reaction may be triggered.In order to solve the above problems,this paper establishes an edge object-linked agent business deployment model for power communication network to unify the management of data collection,resource allocation and task scheduling within the system,realizes the virtualization of object-linked agent computing resources through Docker container technology,designs the target model of network latency and energy consumption,and introduces A3C algorithm in deep reinforcement learning,improves it according to scene characteristics,and sets corresponding optimization strategies.Mini-mize network delay and energy consumption;At the same time,to ensure that sensitive power business is handled in time,this paper designs the business dispatch model and task migration model,and solves the problem of server failure.Finally,the corresponding simulation program is designed to verify the feasibility and validity of this method,and to compare it with other existing mechanisms.展开更多
This paper investigates a wireless powered communication network(WPCN)facilitated by an unmanned aerial vehicle(UAV)in Internet of Things(IoT)networks,where multiple IoT devices(IoTDs)gather energy from a terrestrial ...This paper investigates a wireless powered communication network(WPCN)facilitated by an unmanned aerial vehicle(UAV)in Internet of Things(IoT)networks,where multiple IoT devices(IoTDs)gather energy from a terrestrial energy station(ES)during the wireless energy transfer(WET)stage,followed by the UAV collecting data from these powered IoTDs with the time division multiple access(TDMA)protocol in the wireless information transfer(WIT)stage.To overcome the challenges of radio propagation caused by obstructions,we incorporate a reconfigurable intelligent surface(RIS)to enhance the link quality of the ES-IoTDs and IoTDs-UAV.The primary objective is to maximize the average sum rate of all IoTDs by jointly optimizing UAV trajectory,ES transmit power,and RIS phase shifts,along with the time allocation for WET and WIT.To this end,we reformulate the optimization problem as a markov decision process(MDP)and introduce a deep reinforcement learning(DRL)approach for addressing the formulated problem,called the proximal policy optimization(PPO)based energy harvesting with trajectory design and phase shift optimization(PPO-EHTDPS)algorithm.By continuously exploring within the environment,the PPO algorithm refines its policy to optimize the UAV trajectory,the energy phase shifts,ES transmit power,and WET/WIT time allocation.Additionally,a continuous phase shift optimization algorithm is employed to determine the information phase shifts for each IoTD to maximize average sum rate.Finally,numerical results demonstrate that the proposed PPOEHTDPS algorithm can significantly achieve higher average sum rate and show better convergence performance over the benchmark algorithms.展开更多
文摘With the acceleration of the intelligent transformation of power systems,the requirements for communication technology are increasingly stringent.The application of 5G mobile communication technology in power communication is analyzed.In this study,5G technology features,application principles,and practical strategies are discussed,and methods such as network slicing,customized deployment,edge computing collaborative application,communication equipment integration and upgrading,and multi-technology collaboration and complementation are proposed.It aims to effectively improve the efficiency,reliability,and security of power communication,solve the problem that traditional communication technology is difficult to meet the diversified needs of power business,and achieve the effect of optimizing the power communication network and supporting the intelligent development of the power system.
基金sponsored by the National Natural Science Foundation,Youth Foundation of China,Grant/Award Number:51607146Sichuan Natural Sciences Fund,Grant/Award Number:2023NSFSC0295。
文摘In generator design field,waveform total harmonic distortion(THD)and telephone harmonic factor(THF)are parameters commonly used to measure the impact of generator no-load voltage harmonics on the power communication quality.Tubular hydrogenerators are considered the optimal generator for exploiting low-head,high-flow hydro resources,and they have seen increasingly widespread application in China's power systems recent years.However,owing to the compact and constrained internal space of such generators,their internal magnetic-field harmonics are pronounced.Therefore,accurate calculation of their THD and THF is crucial during the analysis and design stages to ensure the quality of power communication.Especially in the electromagnetic field finite element modeling analysis of such generators,the type and order of the finite element meshes may have a significant impact on the THD and THF calculation results,which warrants in-depth research.To address this,this study takes a real 34 MW large tubular hydrogenerator as an example,and establishes its electromagnetic field finite element model under no-load conditions.Two types of meshes,five mesh densities,and two mesh orders are analyzed to reveal the effect of electromagnetic field finite element mesh types and orders on the calculation results of THD and THF for such generators.
基金supported by the State Grid project which names the simulation and service quality evaluation technology research of power communication network(No.XX71-14-046)
文摘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.
文摘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.
文摘Couplets,as a vital symbol of Chinese traditional culture,hold prominent cultural significance in Beijing’s urban neighborhoods.This paper assesses the current state of cultural communication efficacy regarding couplets in Beijing’s neighborhoods,identifying challenges including fragile cultural ecosystems,limitations of communication agents,homogeneity in content and forms,and outdated dissemination mechanisms.To address these issues,the study conducts an in-depth analysis of strategies to enhance the cultural dissemination capacity of Beijing’s neighborhood couplet culture,proposing comprehensive enhancement pathways.The research aims to effectively elevate the cultural influence of Beijing’s neighborhood couplet culture and facilitate the city’s development as a national cultural center.
基金supported by the Science and Technology Project of State Grid Corporation of China(Grant No.5211XT17001N)
文摘The power communication network can be abstracted as a graph based on its topology. In this paper, we propose an approach to conduct simulations of power communication network based on its graph representation. In particular, the nodes and edges in the graph refer to the ports and channels in the grid topology. Different applications on the grid can be transformed into queries over the graph. Hence, in this paper, we build our grid simulation model based on the Neo4 j graph database. We also propose a fault extension algorithm based on predicate calculus. Our experiment evaluations show that the proposed approach can effectively improve the efficiency of the power grid.
文摘Power line communication(PLC)provides intelligent electrical functions such as power quality measurement,fault surveys,and remote control of electrical network.Most of research works have been done in low voltage(LV)scenario due to the fast development of in-home PLC.The aim of this paper is to evaluate the link-level performance of a medium voltage(MV)MIMO-OFDM communication system based on transmission link under underground power line channel.The MIMO channel is modeled as a modified multipath model in the presence of impulsive noise and background noise.We first perform a measurement on the practical MV MIMO channel parameters for a section of buried cable of 1 km long in Ganzhou city,Jiangxi province,China.Based on the measured channel,we design the frame structure based on an IEEE standard for broadband over power line networks[1]to support MV MIMO-OFDM transmission.According to designed frame structure,we design an encoder and a decoder for a dual binary tail-biting turbo code and optimize some key decoder parameters for low bit error rate performance.Finally,the link-level performance for both spatial multiplexing and spatial diversity are evaluated.Numeral results show that MV MIMO-OFDM is a promising approach to provide both high data rate and link reliability for PLC.
文摘In the past decade,several efforts around the world were started with the goal of introducing "smart metering" capabilities into the power grid.These efforts have spurred renewed interest in the design of next generation Narrowband Power Line Communications(NB-PLC) transceivers.In the past few years,ITU-T and IEEE have standardized a family of next generation OFDM-based NB-PLC transceivers some of which are today being considered for massive deployments in Europe and Asia.This paper addresses the important role that PLC has not only for smart metering but also for many other Smart Grid applications,and also gives an overview of the main differences between these next generation NB-PLC standards.
基金Supported by the National Natural Science Foundation Project (No. 60872073, No. 60975017, and No. 51075068)Doctoral Fund of Education Ministry (No. 2011009213-0004)
文摘Adaptive bit-loading is a key technology in high speed power line communications with the Orthogonal Frequency Division Multiplexing (OFDM) modulation technology. According to the real situation of the transmitting power spectrum limited in high speed power line communications, this paper explored the adaptive bit loading algorithm to maximize transmission bit number when transmitting power spectral density and bit error rate are not exceed upper limit. With the characteristics of the power line channel, first of all, it obtains the optimal bit loading algorithm, and then provides the improved algorithm to reduce the computational complexity. Based on the analysis and simulation, it offers a non-iterative bit allocation algorithm, and finally the simulation shows that this new algorithm can greatly reduce the computational complexity, and the actual bit allocation results close to optimal.
基金financial supports provided by the National Natural Science Foundation of China (No.51274202)the Fundamental Research Funds for the Central Universities (No.2013RC11)+3 种基金the Science and Technology Achievements Transformation Project of Jiangsu Province (No.BA2012068)the Natural Science Foundation of Jiangsu Province (Nos.BK20130199 and BK20131124)Ceeusro Prospective Joint Research Project of Jiangsu Province (No.BY2014028-01)Great Cultivating Special Project at China University of Mining and Technology (No.2014ZDPY16)
文摘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.
文摘Most existing media access control(MAC) protocols in power line communication(PLC) networks just discard the colliding data packets when collision occurs.The collision deteriorates throughput and delay performance of system under high traffic conditions.This article presents a novel media access scheme with fast collision resolution for in-home power line networks.It works by first recognizing the colliding stations through detecting the inserted unique ID sequence ahead of data packets,then the source nodes retransmitting their packets immediately after the collision slot.The proposed protocol maintains the benefits of ALOHA systems.It needs no scheduling overhead and is suitable for bursty sources,such as multimedia data packets.Computer simulations have demonstrated that this approach can achieve high throughput due to its ability of resolving collisions.
基金the National Natural Science Foundation of China(No.60072048)
文摘This letter derives the Equivalent M-band Discrete Wavelet(EMDW) transmission mode of Orthogonal Frequency Division Multiplexing(OFDM) transmission systems, and presents a new Quadrature M-band Discrete Wavelet(QMDW) based OFDM-CDMA(Code Division Multiple Access) communication systems for high speed Power Line Communication (PLC) channels.This system gives much better robustness to Inter-Channel Interference (ICI), Multi-User Interference (MUI) and noise interference, which is verified by simulation.
文摘This paper presents the basic principle of OFDM technology and some key technologies, and do the simulation of OFDM technology. Secondly, on the basis of the design of intelligent Home Furnishing system demand, this paper research and design low voltage power line carrier communication based on Intelligent Home Furnishing system for. The circuit takes ARM Cortex-M3 based on the ARM kernel as the central controller, and realize remote monitoring and control of equipment through the transplantation of uC/OS-II system and the design of Web Serve program. Using OFDM power line carrier communication modes as networking mode of the intelligent Home Furnishing system. Finally, the paper realize the intelligent node and relevant software that constitute a complete system of intelligent Home Furnishing.
基金the National Natural Science Foundation of China under Grants 60572090, 60472045 and 60496313, Ph.D Programs Foundation of Ministry of Education of China under Grant 20050614009.
文摘A new mobile communications network architecture is proposed to solve four existing bottlenecks that restrict the rapid development of mobile communications,as well as to meet the development demands of future broadband mobile communications. The architecture introduces the Information Lamp (IL),a novel device carrying out transceiver function,as the access point,besides providing light. It fulfills information interaction between the access points and radio access network through the power line (or fiber). The new system,supported by core technologies such as multi-antenna based distributed space-time signal processing and distributed radio resource management,integrates the wired and wireless networks to provide high-speed and high-quality mobile communication services.
文摘Power line communication technology is used in various applications, from high voltage network to the low voltage network, as it is the only wired communication technology that is comparable with wireless communication network. It works by injecting a modulated carrier wave into the electric cables from one transceiver to another. But still, the noise level and impedance mismatch are still the main concern of this technology, particularly in the low voltage network in residential area. Power line has additive non-white noise and extremely harsh environment for communication. At the same time, there is signal attenuation along the power line caused by the impedance mismatch in the power line network. Even though these problems can be controlled using a band-pass filter and an impedance matching circuit respectively, but the impedances in the power line are time and location variant and it is rather difficult to design a circuit that allows maximum power transfer in the system all the time. Thus in this paper, a new adaptive impedance matching circuits is proposed for narrowband power line communication. This methodology is derived based on the RLC band-pass filter circuit. This concept is designed to achieve simpler configuration and higher matching resolution.
文摘Acknowledgments Thanks for assistance and support, which is provided by State Grid Corporation of China and State Grid Communication Information & Telecommunication Company, for the project in the process of research and development. Fibrlink Communications Co., Ltd will keep exerting itself to innovating, which aims for making more contribution of the smart grid on energy reduction and environment protection.
文摘The number and creativity of side channel attacks have increased dramatically in recent years. Of particular interest are attacks leveraging power line communication to 1) gather information on power consumption from the victim and 2) exfiltrate data from compromised machines. Attack strategies of this nature on the greater power grid and building infrastructure levels have been shown to be a serious threat. This project further explores this concept of a novel attack vector by creating a new type of penetration testing tool: an USB power adapter capable of remote monitoring of device power consumption and communicating through powerline communications.
基金2024 Innovation Project of Guangxi Graduate Education,Guangxi Normal University(XYCBZ2024005)2024 Innovation Project of Guangxi Graduate Education,Guangxi Normal University(JGY2024066)+5 种基金Research on Path Innovation for Guangxi’s Publishing Power in Promoting the Construction of the China-ASEAN Community of Shared Future(24XWF011),2024 Annual Project of Philosophy and Social Sciences Research in GuangxiTeaching Practice Research on the Cultivation Model of Outstanding Talents in Second Language Communication in the Context of Globalization(2024JGZ14),2024 Key Educational and Teaching Reform Project of Guangxi Normal UniversityResearch on the Knowledge Convergence of Guilin’s Regional Cultural Resources in International Chinese Language Teaching Based on CiteSpace(2024JGXW08),2024 New Engineering and New Liberal Arts Research and Practice Project of Guangxi Normal UniversityResearch Project of International Chinese Education(22YH49C),the Center for Language Exchange and Cooperation of the Ministry of Education of PRC2024–2025 International Chinese Education Collaboration Mechanism Grant Project(24YHXZ014),the Center for Language Exchange and Cooperation of the Ministry of Education of PRC2024–2025 International Chinese Education Collaboration Mechanism Grant Project(24YHXZ013),the Center for Language Exchange and Cooperation of the Ministry of Education of PRC。
文摘The dissemination of Chinese culture to international students in China encompasses two closely interconnected dimensions:first,the dissemination aimed at international students to cultivate their understanding and recognition of the core values of Chinese culture;second,the dissemination of Chinese culture by international students themselves,which involves creating a diversified platform to effectively communicate China’s narratives.From the perspective of external cultural dissemination,this study employs a literature research method combined with CiteSpace knowledge mapping software to analyze and summarize the research network,hotspots,and knowledge structure within the field of international education in China.The exploration of future development directions presents significant practical value and contemporary relevance.
基金funded by the“Research on Digitization and Intelligent Application of Low-Voltage Power Distribution Equipment”[SGSDDK00PDJS2000375]。
文摘The main function of the power communication business is to monitor,control and manage the power communication network to ensure normal and stable operation of the power communication network.Commu-nication services related to dispatching data networks and the transmission of fault information or feeder automation have high requirements for delay.If processing time is prolonged,a power business cascade reaction may be triggered.In order to solve the above problems,this paper establishes an edge object-linked agent business deployment model for power communication network to unify the management of data collection,resource allocation and task scheduling within the system,realizes the virtualization of object-linked agent computing resources through Docker container technology,designs the target model of network latency and energy consumption,and introduces A3C algorithm in deep reinforcement learning,improves it according to scene characteristics,and sets corresponding optimization strategies.Mini-mize network delay and energy consumption;At the same time,to ensure that sensitive power business is handled in time,this paper designs the business dispatch model and task migration model,and solves the problem of server failure.Finally,the corresponding simulation program is designed to verify the feasibility and validity of this method,and to compare it with other existing mechanisms.
文摘This paper investigates a wireless powered communication network(WPCN)facilitated by an unmanned aerial vehicle(UAV)in Internet of Things(IoT)networks,where multiple IoT devices(IoTDs)gather energy from a terrestrial energy station(ES)during the wireless energy transfer(WET)stage,followed by the UAV collecting data from these powered IoTDs with the time division multiple access(TDMA)protocol in the wireless information transfer(WIT)stage.To overcome the challenges of radio propagation caused by obstructions,we incorporate a reconfigurable intelligent surface(RIS)to enhance the link quality of the ES-IoTDs and IoTDs-UAV.The primary objective is to maximize the average sum rate of all IoTDs by jointly optimizing UAV trajectory,ES transmit power,and RIS phase shifts,along with the time allocation for WET and WIT.To this end,we reformulate the optimization problem as a markov decision process(MDP)and introduce a deep reinforcement learning(DRL)approach for addressing the formulated problem,called the proximal policy optimization(PPO)based energy harvesting with trajectory design and phase shift optimization(PPO-EHTDPS)algorithm.By continuously exploring within the environment,the PPO algorithm refines its policy to optimize the UAV trajectory,the energy phase shifts,ES transmit power,and WET/WIT time allocation.Additionally,a continuous phase shift optimization algorithm is employed to determine the information phase shifts for each IoTD to maximize average sum rate.Finally,numerical results demonstrate that the proposed PPOEHTDPS algorithm can significantly achieve higher average sum rate and show better convergence performance over the benchmark algorithms.