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Link Budget and Enhanced Communication Distance for Ambient Internet of Things
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作者 YANG Yibing LIU Ming +2 位作者 XU Rongtao WANG Gongpu GONG Wei 《ZTE Communications》 2024年第1期16-23,共8页
Backscatter communications will play an important role in connecting everything for beyond 5G(B5G)and 6G systems.One open challenge for backscatter communications is that the signals suffer a round-trip path loss so t... Backscatter communications will play an important role in connecting everything for beyond 5G(B5G)and 6G systems.One open challenge for backscatter communications is that the signals suffer a round-trip path loss so that the communication distance is short.In this paper,we first calculate the communication distance upper bounds for both uplink and downlink by measuring the tag sensitivity and reflection coefficient.It is found that the activation voltage of the envelope detection diode of the downlink tag is the main factor limiting the back-scatter communication distance.Based on this analysis,we then propose to implement a low-noise amplifier(LNA)module before the envelope detection at the tag to enhance the incident signal strength.Our experimental results on the hardware platform show that our method can increase the downlink communication range by nearly 20 m. 展开更多
关键词 ambient IoT(AIoT) B5G backscatter communication link budget low-noise amplifier(LNA) Release 19 tag chip sensitivity upper bounds
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Containment-Based Multiple PCC Voltage Regulation Strategy for Communication Link and Sensor Faults
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作者 Meina Zhai Qiuye Sun +1 位作者 Rui Wang Huaguang Zhang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第11期2045-2055,共11页
The distributed AC microgrid(MG) voltage restoration problem has been extensively studied. Still, many existing secondary voltage control strategies neglect the co-regulation of the voltage at the point of common coup... The distributed AC microgrid(MG) voltage restoration problem has been extensively studied. Still, many existing secondary voltage control strategies neglect the co-regulation of the voltage at the point of common coupling(PCC) in the AC multi-MG system(MMS). When an MMS consists of sub-MGs connected in series, power flow between the sub-MGs is not possible if the PCC voltage regulation relies on traditional consensus control objectives. In addition, communication faults and sensor faults are inevitable in the MMS. Therefore, a resilient voltage regulation strategy based on containment control is proposed.First, the feedback linearization technique allows us to deal with the nonlinear distributed generation(DG) dynamics, where the PCC regulation problem of an AC MG is transformed into an output feedback tracking problem for a linear multi-agent system(MAS) containing nonlinear dynamics. This process is an indispensable pre-processing in control algorithm design. Moreover, considering the unavailability of full-state measurements and the potential faults present in the sensors, a novel follower observer is designed to handle communication faults. Based on this, a controller based on containment control is designed to achieve voltage regulation. In regulating multiple PCC voltages to a reasonable upper and lower limit, a voltage difference exists between sub-MGs to achieve power flow. In addition, the secondary control algorithm avoids using global information of directed communication network and fault boundaries for communication link and sensor faults. Finally, the simulation results verify the performance of the proposed strategy. 展开更多
关键词 communication link faults directed graph fully distributed control voltage regulation control
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Frequency-Hopping Frequency Reconnaissance and Prediction for Non-cooperative Communication Network 被引量:6
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作者 Gao Li Wei Wang +2 位作者 Guoru Ding Qihui Wu Zitong Liu 《China Communications》 SCIE CSCD 2021年第12期51-64,共14页
The continuous change of communica-tion frequency brings difficulties to the reconnaissance and prediction of non-cooperative communication net-works.Since the frequency-hopping(FH)sequence is usually generated by a c... The continuous change of communica-tion frequency brings difficulties to the reconnaissance and prediction of non-cooperative communication net-works.Since the frequency-hopping(FH)sequence is usually generated by a certain model with certain regularity,the FH frequency is thus predictable.In this paper,we investigate the FH frequency reconnais-sance and prediction of a non-cooperative communi-cation network by effective FH signal detection,time-frequency(TF)analysis,wavelet detection and fre-quency estimation.With the intercepted massive FH signal data,long short-term memory(LSTM)neural network model is constructed for FH frequency pre-diction.Simulation results show that our parameter es-timation methods could estimate frequency accurately in the presence of certain noise.Moreover,the LSTM-based scheme can effectively predict FH frequency and frequency interval. 展开更多
关键词 non-cooperative communication network frequency-hopping frequency prediction LSTM
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Social-Aware Joint Mode Selection and Link Allocation for Device-to-Device Communication Underlaying Cellular Networks 被引量:1
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作者 Lianxin Yang Dan Wu +2 位作者 Hongkui Shi Yanshan Long Yueming Cai 《China Communications》 SCIE CSCD 2018年第8期92-107,共16页
Joint mode selection and link allocation are crucial to achieve the advantage of Device-to-Device(D2 D) communications in improving spectral efficiency. In practice, cellular users tend to not be totally altruistic or... Joint mode selection and link allocation are crucial to achieve the advantage of Device-to-Device(D2 D) communications in improving spectral efficiency. In practice, cellular users tend to not be totally altruistic or absolutely selfish. How to stimulate them to devote their links and how to allocate their links to D2 D pair candidates efficiently are two main challenges. In this paper, we encourage cellular users through the variable payment with regard to the social tie strength between cellular users and D2 D pair candidates. In particular, the social tie strength is inferred through a graph inference model and its impact on the payment is quantified as a negative exponential function. Then, we propose a resource scheduling optimization model based on the non-transferable utility coalition formation game, and a distributed coalition formation algorithm based on the Pareto preference and merge-and-split rule. From them, the final coalition structure is obtained, which reflects the strategy of mode selection and link allocation. Numerical results are presented to verify the effectiveness of our proposed scheme. 展开更多
关键词 D2D communication mode selection link allocation social ties coalition formation game
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Study of Communication Protocol and Link Establishing Mode of Mine Managing Mobile Communication System of Minute Areas
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作者 杨维 孙继平 苏又平 《International Journal of Mining Science and Technology》 2000年第2期79-82,共4页
This paper studies the communication protocol and link establishing mode of the mine managing mobile communication system consisted of minute areas. The communication protocol suitable for the system is proposed and d... This paper studies the communication protocol and link establishing mode of the mine managing mobile communication system consisted of minute areas. The communication protocol suitable for the system is proposed and designed. 展开更多
关键词 MINE mobile communication communication protocol LAYER link
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Model and Implementation of Communication Link Management Supporting High Availability
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作者 LuoJuan CaoYang +1 位作者 HeZheng LiFeng 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第1期68-72,共5页
Despite the rapid evolution in all aspects of computer technology, both the computer hardware and software are prone to numerous failure conditions. In this paper, we analyzed the characteristic of a computer system a... Despite the rapid evolution in all aspects of computer technology, both the computer hardware and software are prone to numerous failure conditions. In this paper, we analyzed the characteristic of a computer system and the methods of constructing a system, proposed a communication link management model supporting high availability for network applications, Which will greatly increase the high availability of network applications. Then we elaborated on heartbeat or service detect, fail-over, service take-over, switchback and error recovery process of the model. In the process of constructing the communication link, we implemented the link management and service take-over with high availability requirement, and discussed the state and the state transition of building the communication link between the hosts, depicted the message transfer and the start of timer. At Last, we applied the designed high availability system to a network billing system, and showed how the system was constructed and implemented, which perfectly satisfied the system requirements. Key words high availability - service take-over - fail-over - communication link management CLC number TP 393 Foundation item: Supported by the National Natural Science Foundation of China (60132030)Biography: Luo Juan (1974-), female, Ph. D candidate, research direction: high speed network and information security. 展开更多
关键词 high availability service take-over fail-over communication link management
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D2D communication in a cellular network based on link adaptation with truncated ARQ
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作者 李军龙 费泽松 +2 位作者 黄盖世 傅友 邢成文 《Journal of Beijing Institute of Technology》 EI CAS 2013年第4期519-523,共5页
A device-to-device (D2D) communication mode underlaying cellular network in a single- cell environment is introduced. A practical method based on link adaptation with automatic repeat request (ARQ) is presented. L... A device-to-device (D2D) communication mode underlaying cellular network in a single- cell environment is introduced. A practical method based on link adaptation with automatic repeat request (ARQ) is presented. Link adaptation technique, which combines adaptive modulation and coding ( AMC ) with truncated ARQ, can maximize the cellular UEs' data rate under prescribed delay and performance constraints. The proposed method can maximize the total transmission rate when an outage probability is determined. Numerical results show that with proper power control, the in- terference between the two links can be coordinated to increase the sum rate without overwhelming the cellular service. 展开更多
关键词 device-to-device (D2D) communication link adaptation automatic repeat request( ARQ
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System Design Of Security Evaluation For Data Link Communications
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作者 Feng Haixun ZangYong 《International Journal of Technology Management》 2014年第7期46-47,共2页
Data link communication requires data communication process must have reliability, availability, confidentiality, availability, integrity, non-repudiation, controllability.This has a great effect to ensure the normal ... Data link communication requires data communication process must have reliability, availability, confidentiality, availability, integrity, non-repudiation, controllability.This has a great effect to ensure the normal communication functions.In this paper the author on the basis of many years of work experience, first discussed the establishment of a risk assessment system data link,then focused on the problem of index weight assessment.To data communication security, this research article will provide some references. 展开更多
关键词 Data link communications security AHP
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A case study on knowledge communication based on friends-list links in the science blogging community at Sciencenet.cn
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作者 Junping QIU Feifei WANG Houqiang YU 《Chinese Journal of Library and Information Science》 2011年第Z1期49-64,共16页
Sciencenet.cn is the leading online portal serving the Chinese scientific community. This paper intends to analyze the interdisciplinary and intradisciplinary knowledge communication patterns based on friends-list lin... Sciencenet.cn is the leading online portal serving the Chinese scientific community. This paper intends to analyze the interdisciplinary and intradisciplinary knowledge communication patterns based on friends-list links in the blog community at Sciencenet.cn by using hyperlink analysis and social network analysis. The major findings are: 1) More bloggers have an academic background in management science and life science; 2) there are some core actors in co-inlink network and co-outlink network, who take the lead in engaging with knowledge exchange activities and produce a great influence on interdisciplinary communication; 3) interactive relationships commonly exist between a blogger and those on his/her friends list, and the most linked-to blogs usually play a key role in generating interactive communication; 4) management science has the highest co-inlink count with life science or information science and it has the highest co-outlink count with life science or mathematical and physical science; 5) management science and life science have the greatest impact on information science and the interdisciplinary knowledge communication will also produce relatively significant influence on the development of information science discipline. It is our hope that this research can serve as a reference source for the future studies of academic virtual communities, and the development of mechanisms for facilitating increased engagement in knowledge exchange activities in academic virtual communities. 展开更多
关键词 Academic blog community Hyperlink analysis Social network analysis(SNA) Friends-list links Knowledge communication Academic community
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A fully distributed robust optimal control approach for air-conditioning systems considering uncertainties of communication link in IoT-enabled building automation systems
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作者 Wenzhuo Li Rui Tang Shengwei Wang 《Energy and Built Environment》 2024年第3期446-454,共9页
Internet of Things(IoT)technologies are increasingly implemented in buildings as the cost-effective smart sens-ing infrastructure of building automation systems(BASs).They are also dispersed computing resources for no... Internet of Things(IoT)technologies are increasingly implemented in buildings as the cost-effective smart sens-ing infrastructure of building automation systems(BASs).They are also dispersed computing resources for novel distributed optimal control approaches.However,wireless communication networks are critical to fulfill these tasks with the performance influenced by inherent uncertainties in networks,e.g.,unpredictable occurrence of link failures.Centralized and hierarchical distributed approaches are vulnerable against link failure,while the robustness of fully distributed approaches depends on the algorithms adopted.This study therefore proposes a fully distributed robust optimal control approach for air-conditioning systems considering uncertainties of com-munication link in IoT-enabled BASs.The distributed algorithm is adopted that agents know their out-neighbors only.Agents directly coordinate with the connected neighbors for global optimization.Tests are conducted to test and validate the proposed approach by comparing with existing approaches,i.e.,the centralized,the hierarchical distributed and the fully distributed approaches.Results show that different approaches are vulnerable against to uncertainties of communication link to different extents.The proposed approach always guarantees the optimal control performance under normal conditions and conditions with link failures,verifying its high robustness.It also has low computation complexity and high optimization efficiency,thus applicable on IoT-enabled BASs. 展开更多
关键词 Multi-agent system Edge computing Air-conditioning system Internet of Things(IoT) communication link failure
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Resource Allocation Method of Device-to-Device Communication 被引量:1
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作者 Wenji Feng Yafeng Wang Lei Yang 《Communications and Network》 2013年第3期338-343,共6页
In this paper, we study D2D (Device-to-Device) communication underlying LTE-Advanced uplink system. Since D2D communication reuses uplink resources with cellular communication in this scenario, it’s hard to avoid the... In this paper, we study D2D (Device-to-Device) communication underlying LTE-Advanced uplink system. Since D2D communication reuses uplink resources with cellular communication in this scenario, it’s hard to avoid the inference between D2D users and cellular users. If there is no restriction for D2D communication on using the whole uplink frequency band, it will have a strong negative impact on cellular communication. In order to overcome this shortage, we propose a resource allocation method that D2D users and cellular users use orthogonal frequency resources. This method will effectively reduce the inference between both kinds of communication. However, an obvious disadvantage of this method is no effective use of uplink resources. Based on this, we propose an optimized resource allocation method that a specific cellular user will be chosen to reuse the RBs (Resource Block) of D2D users. These ideas will be taken into system-level simulation, and from the results of simulation we can see that the optimized method has the ability to improve overall system performance and limit inference for cell-edge users. 展开更多
关键词 Device-to-device communication LTE-ADVANCED System RESOURCE ALLOCATION Method up link Cell-edge USERS
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High Capacity Data Rate System:Review of Visible Light Communications Technology 被引量:1
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作者 Augustus Ehiremen Ibhaze Patience Ebehiremen Orukpe Frederick Obataimen Edeko 《Journal of Electronic Science and Technology》 CAS CSCD 2020年第3期241-265,共25页
Wireless communications have become an integral part of global convergence as global connectedness has gradually become dependent on its efficient deployment.The need for"more-broadband"techniques in relatio... Wireless communications have become an integral part of global convergence as global connectedness has gradually become dependent on its efficient deployment.The need for"more-broadband"techniques in relation to the ever increasing growth rate of the data hungry society now necessitates novel techniques for the high-speed data transmission.While advancements have been made in this regard,the projection of having an eventual Internet of everything (IoE) deployment will result in an unimaginable transmission data rate requirement as huge data traffic will be conveyed per time within the communications network,which will require a capacity upgrade of the existing infrastructure.Visible light communications (VLCs),as an integral part of optical wireless communications (OWCs),have been reviewed in this article,having the capacity to extend the achievable data rate requirement of the wireless communications network.The technologies,techniques,and best practices have been presented alongside technology integration for the seamless high capacity wireless broadband deployment. 展开更多
关键词 Channel equalization heterogeneous network(HetNet) light-fidelity(Li-Fi) propagation link visible light communications(VLCs) wireless-fidelity(Wi-Fi)
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Research and Development of a Communication Monitor to a Distribution Management System
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作者 杨公训 王健康 +1 位作者 周春良 杨彦从 《Journal of China University of Mining and Technology》 2002年第1期43-47,共5页
Based on the existed equipment (the power line carrier, optic fiber, twisted pair and wireless apparatus) being used to the same route in the current communication net of distribution management system (DMS), this pap... Based on the existed equipment (the power line carrier, optic fiber, twisted pair and wireless apparatus) being used to the same route in the current communication net of distribution management system (DMS), this paper presents a new kind of communication monitor DMS, which provides a communication monitoring interface and then by DMS, data transfer problem from field terminal unit to junction center station can be solved and the communication channels can also be supervised. At the same time, synthetically using computer communication, internet technology and database technology, this system can realize the real time monitoring and fault locating in the communication network. 展开更多
关键词 communication monitor system link control unit (LCU) distribution management system(DMS) DATABASE
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Millimeter Wave Communication for Cellular and Cellular-802.11 Hybrid Networks
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作者 Philip Pietraski I-tai Lu 《ZTE Communications》 2012年第4期1-2,共2页
The demand for wireless data has been driving network capacity to double about every two years for the past 50 years, if not 100 years, and this has come to be known as Cooper's Law. In recent years, this trend has a... The demand for wireless data has been driving network capacity to double about every two years for the past 50 years, if not 100 years, and this has come to be known as Cooper's Law. In recent years, this trend has accelerated as a greater proportion of the population adopts wireless devices with ever greater capabilities, including tablets that support HD video and other advanced capabilities. 展开更多
关键词 Millimeter Wave communication for Cellular and Cellular-802.11 Hybrid Networks link
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Non‐Negligible Influences of Rain on 5G Millimeter Wave Terrestrial Communication System
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作者 GONG Shuhong ZHANG Xingmin +1 位作者 DOU Jianwu HUANG Weifang 《ZTE Communications》 2020年第3期64-70,共7页
The impacts of rain on millimeter wave(mmW)terrestrial links,which are inevitably affected by ground-objects-induced multipath propagation,are presented based on the signal time series data measured at 35 GHz.We analy... The impacts of rain on millimeter wave(mmW)terrestrial links,which are inevitably affected by ground-objects-induced multipath propagation,are presented based on the signal time series data measured at 35 GHz.We analyze the coupled influence mechanism of rain-induced and ground-objects-induced multipath propagation on mmW terrestrial links.It can be deduced that the rain-induced impacts on millimeter wave terrestrial links cannot be neglected.The results given in this paper are significant for developing 5G millimeter wave terrestrial mobile communication links. 展开更多
关键词 5G communication mmW MULTIPATH rain-caused effects terrestrial links
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Acquisition and Tracking Technology for Space Laser Communication
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作者 ZHANG Jinlong CHEN Anhe +4 位作者 ZHANG Wenrui ZHANG Jianhua BIAN Jingying ZHANG Ruofan REN Bin 《Aerospace China》 2020年第3期13-21,共9页
The divergence angle of laser beam used in space laser communication is usually no more than 100μrad.Using laser beam with small divergence angle to achieve acquisition and tracking for space laser link has always be... The divergence angle of laser beam used in space laser communication is usually no more than 100μrad.Using laser beam with small divergence angle to achieve acquisition and tracking for space laser link has always been a difficult problem.In addition,the random nature of the atmosphere will affect the satellite-ground laser link,which increases the difficulty of the acquisition and stable tracking for the laser link.Thus,taking into account the above challenges for satellite-ground laser communication,an acquisition and tracking scheme of using both beacon beam and signal beam was designed for the Laser Communication Terminal(LCT)of Shijian 20 satellite.In-orbit test results indicated that under the condition of moderate atmospheric turbulence(atmospheric coherence length r0≈3 cm),the process of acquisition and tracking for the satellite-ground laser link can be completed within 1 s after the initial pointing between the LCT and Optical Ground Station(OGS)is performed,and the tracking error was less than 1μrad(3σ).In addition,the laser link can be re-established quickly once being interrupted by unsteady atmospheric turbulence,and can be maintained for a long time under moderate twurbulence conditions,which lays a foundation for future application of satellite-ground laser communication. 展开更多
关键词 space laser communication Shijian 20 satellite satellite-ground laser link acquisition and trackin
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Shortest Link Scheduling in Wireless Networks with Oblivious Power Control 被引量:1
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作者 Chunmei Ma Jiguo Yu +1 位作者 Baogui Huang Yu Meng 《China Communications》 SCIE CSCD 2021年第4期137-152,共16页
Link scheduling has always been a fundamental problem in wireless networks for its direct impacts on the performance of wireless networks such as throughput capacity,transmission delay,lifetime,etc.Existing work is ma... Link scheduling has always been a fundamental problem in wireless networks for its direct impacts on the performance of wireless networks such as throughput capacity,transmission delay,lifetime,etc.Existing work is mainly established under graphbased models,which are not only impractical but also incorrect due to the essentially fading characteristics of signals.In this paper,we study the shortest link scheduling problem under two more realistic models,namely the signal to interference plus noise ratio(SINR)model and the Rayleigh fading model.We propose a centralized square-based scheduling algorithm(CSSA)with oblivious power control under the SINR model and prove its correctness under both the SINR model and the Rayleigh fading model.Furthermore,we extend CSSA and propose a distributed square-based scheduling algorithm(DSSA).Note that DSSA adopts CSMA/CA so that a wireless node can compete for the wireless channel before starting its communication.We also show theoretical analysis and conduct extensive simulations to exhibit the correctness and efficiency of our algorithms. 展开更多
关键词 link scheduling SINR Rayleigh fading wireless networks wireless communications
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SWRR:The Link Scheduling Algorithm Based on Weighted Round-Robin 被引量:1
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作者 Tianbo Lu Ru Yan +3 位作者 Chao Li Lihua Yin Hao Chen Xieyu Zou 《Computers, Materials & Continua》 SCIE EI 2019年第6期965-982,共18页
With the rapid development of the Internet,people pay more and more attention to the protection of privacy.The second-generation onion routing system Tor is the most commonly used among anonymous communication systems... With the rapid development of the Internet,people pay more and more attention to the protection of privacy.The second-generation onion routing system Tor is the most commonly used among anonymous communication systems,which can be used to protect user privacy effectively.In recent years,Tor’s congestion problem has become the focus of attention,and it can affect Tor’s performance even user experience.Firstly,we investigate the causes of Tor network congestion and summarize some link scheduling algorithms proposed in recent years.Then we propose the link scheduling algorithm SWRR based on WRR(Weighted Round Robin).In this process,we design multiple weight functions and compare the performance of these weight functions under different congestion conditions,and the appropriate weight function is selected to be used in our algorithms based on the experiment results.Finally,we also compare the performance of SWRR with other link scheduling algorithms under different congestion conditions by experiments,and verify the effectiveness of the algorithm SWRR. 展开更多
关键词 Weighted Round-Robin TOR congestion control link scheduling anonymous communication
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Model Based Data Transmission: Analysis of Link Budget Requirement Reduction 被引量:1
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作者 Jeremy Straub 《Communications and Network》 2012年第4期278-287,共10页
Communications capability can be a significant constraint on the utility of a spacecraft. While conventionally enhanced through the use of a larger transmitting or receiving antenna or through augmenting transmission ... Communications capability can be a significant constraint on the utility of a spacecraft. While conventionally enhanced through the use of a larger transmitting or receiving antenna or through augmenting transmission power, communications capability can also be enhanced via incorporating more data in every unit of transmission. Model Based Transmission Reduction (MBTR) increases the mission utility of spacecraft via sending higher-level messages which rely on preshared (or, in some cases, co-transmitted) data. Because of this a priori knowledge, the amount of information contained in a MBTR message significantly exceeds the amount the amount of information in a conventional message. MBTR has multiple levels of operation;the lowest, Model Based Data Transmission (MBDT), utilizes a pre-shared lower-resolution data frame, which is augmented in areas of significant discrepancy with data from the higher-resolution source. MBDT is examined, in detail, herein and several approaches to minimizing the required bandwidth for conveying data required to conform to a minimum level of accuracy are considered. Also considered are ways of minimizing transmission requirements when both a model and change data required to attain a desired minimum discrepancy threshold must be transmitted. These possible solutions are compared to alternate transmission techniques including several forms of image compression. 展开更多
关键词 SPACECRAFT communicationS Data Compression Satellite communicationS link BUDGET REDUCTION Image FORMAT
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Performance Metrics and Delay Thresholds for Multi-Link Cluster Monitoring in Seismic Profession
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作者 王小明 李德敏 +1 位作者 汤海涅 张光林 《Journal of Donghua University(English Edition)》 EI CAS 2016年第3期439-443,共5页
Seismic cluster nodes can be monitored by monitoring system,but thresholds for link failure alarm in monitoring systems are not determined presently,especially in different types of cluster links.Communication link ty... Seismic cluster nodes can be monitored by monitoring system,but thresholds for link failure alarm in monitoring systems are not determined presently,especially in different types of cluster links.Communication link types are discussed in seismic profession.By analyzing the characteristics of various links,the main performance metric,network latency,was proposed,which influenced states of communication links and gave the monitoring results deviation formula for judging the cluster monitoring system at different delay thresholds settings based on multiple-link delay error ratio analysis algorithm we offered.From the final experimental data of the monitoring system,fault alarm thresholds settings were posed under five different communication links,which had the instruction significance to the cluster monitoring in seismic profession. 展开更多
关键词 CLUSTER communication link DELAY THRESHOLD monitoring
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