The traditional methods of weak harmonic signal detection under strong chaotic interference often suffer from high computational complexity and poor performance. In this paper, an Extended Kalman Filter (EKF) based de...The traditional methods of weak harmonic signal detection under strong chaotic interference often suffer from high computational complexity and poor performance. In this paper, an Extended Kalman Filter (EKF) based detection method is proposed for the detection of weak harmonic signal. The EKF method avoids matrix inversion by iterating measurement equation and state equation, which simultaneously improves the robustness and reduces the complexity. Compared with the existing detection methods, the proposed method has the following advantages: 1) it has better performance than the neural network method;2) it has similar performance with the optimal filtering method, but with lower computational complexity;3) it is more robust compared with the optimal filtering method.展开更多
In this paper,we propose a joint channel estimation and symbol detection(JCESD)algorithm relying on message-passing algorithms(MPA)for orthogonal frequency division multiple access(OFDMA)systems.The channel estimation...In this paper,we propose a joint channel estimation and symbol detection(JCESD)algorithm relying on message-passing algorithms(MPA)for orthogonal frequency division multiple access(OFDMA)systems.The channel estimation and symbol detection leverage the framework of expectation propagation(EP)and belief propagation(BP)with the aid of Gaussian approximation,respectively.Furthermore,to reduce the computation complexity involved in channel estimation,the matrix inversion is transformed into a series of diagonal matrix inversions through the Sherman-Morrison formula.Simulation experiments show that the proposed algorithm can reduce the pilot overhead by about 50%,compared with the traditional linear minimum mean square error(LMMSE)algorithm,and can approach to the bit error rate(BER)performance bound of perfectly known channel state information within 0.1 dB.展开更多
An asynchronous transmission scenario for non-orthogonal multiple access(NOMA)user signals with arbitrary phase offset is investigated in this paper.To improve the system performance in the user power-balanced conditi...An asynchronous transmission scenario for non-orthogonal multiple access(NOMA)user signals with arbitrary phase offset is investigated in this paper.To improve the system performance in the user power-balanced conditions,we adopt a synthetic detection method at the receiver,i.e.,the jointly optimal maximal likelihood detection aided triangular successive interference cancellation(JO ML-TSIC)method.Analytical bit error rate(BER)solutions are obtained for a two-user case with the optimal,intentional onehalf symbol period time delay implemented between the user signals.Furthermore,closed-form BER solutions for the case using the triangular successive interference cancellation(TSIC)detection method are also derived for comparisons.Numerical results show that the JO ML-TSIC receiver for the asynchronous system outperforms the TSIC receiver as well as the synchronous successive interference cancellation(SIC)receiver in all the conditions concerned.The results also show that the superiority of the JO ML-TSIC receiver is strengthened when the signals experience flat Rayleigh fading channels compared to the TSIC and the synchronous SIC receivers.展开更多
With the rapid development of smart devices and mobile networks,multimedia services will dominate most of data traffic in 4G/5G networks.Applications -such as conversational videos,online multimedia sharing,remote edu...With the rapid development of smart devices and mobile networks,multimedia services will dominate most of data traffic in 4G/5G networks.Applications -such as conversational videos,online multimedia sharing,remote education,etc.have gained their popularity and will become more ubiquitous among customers.Tra-展开更多
The history of wireless communications can be divided into two eras.The first was a discovery-inspired era,initiated by the great physicist Maxwell’s discovery of the classical theory of electromagnetism,while the se...The history of wireless communications can be divided into two eras.The first was a discovery-inspired era,initiated by the great physicist Maxwell’s discovery of the classical theory of electromagnetism,while the second was a technology-driven era that began with Marconi’s creation of the first practical world-wide radio-based wireless telegraph system,Shannon’s information theory,and the later invention of cellular mobile communications from the first generation(1G)to the fourth(4G).Nowadays,the fifth generation(5G)is regarded as a leading information and communication technology.展开更多
This paper gives a definition of the Industrial Internet and expounds on the academic connotation of the future Industrial Internet.From this foundation,we outline the development and current status of the Industrial ...This paper gives a definition of the Industrial Internet and expounds on the academic connotation of the future Industrial Internet.From this foundation,we outline the development and current status of the Industrial Internet in China and globally.Moreover,we detail the avant-garde paradigms encompassed within the National Natural Science Foundation of China(NSFC)’s“Future Industrial Internet Fundamental Theory and Key Technologies”research plan and its corresponding management strategies.This research initiative endeavors to enhance interdisciplinary collaborations,aiming for a synergistic alignment of industry,academia,research,and practical implementations.The primary focus of the research plan is on the pivotal scientific challenges inherent to the future industrial internet.It is poised to traverse the“first mile”,encompassing foundational research and pioneering innovations specific to the industrial internet,and seamlessly bridges to the“last mile”,ensuring the effective commercialization of scientific and technological breakthroughs into tangible industrial market applications.The anticipated contributions from this initiative are projected to solidify both the theoretical and practical scaffolding essential for the cultivation of a globally competitive industrial internet infrastructure in China.展开更多
In the midst of the fourth industrial revolution,the convergence of the digital,physical,and biological realms is propelling industrial innovation to new heights.At the heart of this transformative era lies the Indust...In the midst of the fourth industrial revolution,the convergence of the digital,physical,and biological realms is propelling industrial innovation to new heights.At the heart of this transformative era lies the Industrial Internet,a pivotal technology reshaping our industries.This powerful force establishes an all-encompassing network[1-2].展开更多
Unmanned aerial vehicle (UAV)-based edge computing is an emerging technology that provides fast task processing for a wider area. To address the issues of limited computation resource of a single UAV and finite commun...Unmanned aerial vehicle (UAV)-based edge computing is an emerging technology that provides fast task processing for a wider area. To address the issues of limited computation resource of a single UAV and finite communication resource in multi-UAV networks, this paper joints consideration of task offloading and wireless channel allocation on a collaborative multi-UAV computing network, where a high altitude platform station (HAPS)is adopted as the relay device for communication between UAV clusters consisting of UAV cluster heads (ch-UAVs) and mission UAVs (m-UAVs). We propose an algorithm, jointing task offloading and wireless channel allocation to maximize the average service success rate (ASSR)of a period time. In particular,the simulated annealing(SA)algorithm with random perturbations is used for optimal channel allocation,aiming to reduce interference and minimize transmission delay.A multi-agent deep deterministic policy gradient (MADDPG) is proposed to get the best task offloading strategy. Simulation results demonstrate the effectiveness of the SA algorithm in channel allocation. Meanwhile,when jointly considering computation and channel resources,the proposed scheme effectively enhances the ASSR in comparison to other benchmark algorithms.展开更多
Beam scheduling is one of the most important issues regarding data relay satellite systems,which can improve the utilization efficiency of limited system resources by programming beam allocation for relay missions.The...Beam scheduling is one of the most important issues regarding data relay satellite systems,which can improve the utilization efficiency of limited system resources by programming beam allocation for relay missions.The ever-increasing relay missions create a substantial challenge for beam scheduling due to an increase in different mission demands.The cooperative usage of different beams further increases the complexity of this problem.Therefore,we develop a novel optimization method to solve the beam scheduling problem for the scenario of various mission demands in the data relay satellite system(DRSS).Based on the analysis of mission demands and resource features,we first construct a heterogeneous parallel machines scheduling model to formulate the beam scheduling problem in the DRSS.To solve this complicated model,we investigate the matching method between mission demands and beam resources,and introduce two concepts,the loose duration and the number of available beams,to make the matching process more effective.Then,the following three algorithms are proposed.Our first approach,the maximized completion probability algorithm(MCPA),applies a greedy strategy based on the new concepts to allocate beams for missions;and two improved versions of this algorithm are also presented,which employ the strategies of mission insertion optimization and mission sequence optimization,respectively.Our simulation results show that the proposed algorithms are superior to the existing algorithms in terms of the scheduled missions,the weight of scheduled missions,and the processing time,which significantly improves the performance of beam scheduling in the DRSS.展开更多
Nowadays,cloud computing has been identified as new opportunities for migrating to the expected agility,reuse,and adaptive capabilities that can support the ever changing IT trends and requirements.Unfortunately,the r...Nowadays,cloud computing has been identified as new opportunities for migrating to the expected agility,reuse,and adaptive capabilities that can support the ever changing IT trends and requirements.Unfortunately,the rapid evolution of those technologies also comes with open issues such as security,privacy,integrity,quality of services,and their possible detrimental consequences.In this work,the concept of insurance is introduced to compensate the cloud computing customers when encountering those failures if service providers(SPs)have insurance purchased.Particularly,we consider the situation when the insurer is unable to see the system failure risk levels of the SPs,which is usually seen as an incomplete information market,in contrast with the optimal situation in a complete information market.First,an insurance-based cloud computing architecture is proposed to build a monetary credit system in which the cloud computing SP pays a premium for a certain coverage to the insurer.Subsequently,problem is formulated to solve the optimal insurance plan in complete and incomplete information markets,together with detail analysis of insurance policies in both cases are provided.Furthermore,simulation results show the properties of the two insurance plans and parameters that affect the design of the insurance plan.展开更多
The space-air-ground network architecture integrates satellite systems,aerial networks,and terrestrial networks,where the unmanned aerial vehicle(UAV)communication in the air segment has attracted particular interest ...The space-air-ground network architecture integrates satellite systems,aerial networks,and terrestrial networks,where the unmanned aerial vehicle(UAV)communication in the air segment has attracted particular interest and demonstrated tremendous potential in both military and civilian applications.Orthogonal frequency division multiplexing(OFDM)can be an effective solution to provide high rate and reliable transmission in UAV communication systems because of its high spectral efficiency and robustness against frequency selective fading.We herein focus our attention on two critical issues in our proposed UAV aided OFDM system,i.e.,timing synchronization and ranging.Moreover,extensive simulations are conducted for evaluation.Finally,we design a real-world field test for verifying the effectiveness of our proposed multi-UAV OFDM communication system.展开更多
Thanks to the recent advances in SIS(Space Information Science)and increasingly mature technologies,network simulations have attracted much attention,which play vital roles in research on validation of the correctness...Thanks to the recent advances in SIS(Space Information Science)and increasingly mature technologies,network simulations have attracted much attention,which play vital roles in research on validation of the correctness of SIN’s(Space Information Network)solutions.In this paper,we constitute an architecture of a hardware-in-the-loop simulation system,where we use a server to act as a real satellite of SINs.Moreover,we model the channel of the satellite network relying on real cables and servers by referring to the Corazza model.Furthermore,based on the data of real weather events,we propose a coordinate mode for reducing LEO’s(Low Earth Orbit)communication delay and validate the efficiency of our proposed method on simulation platform by simplifying the problem to a shortest path problem.展开更多
基金the National Natural Science Foundation of China (Grant No. 61871102 and 61731006)Sichuan province science and technology support program under Grant N0. 2017GZ0345.
文摘The traditional methods of weak harmonic signal detection under strong chaotic interference often suffer from high computational complexity and poor performance. In this paper, an Extended Kalman Filter (EKF) based detection method is proposed for the detection of weak harmonic signal. The EKF method avoids matrix inversion by iterating measurement equation and state equation, which simultaneously improves the robustness and reduces the complexity. Compared with the existing detection methods, the proposed method has the following advantages: 1) it has better performance than the neural network method;2) it has similar performance with the optimal filtering method, but with lower computational complexity;3) it is more robust compared with the optimal filtering method.
文摘In this paper,we propose a joint channel estimation and symbol detection(JCESD)algorithm relying on message-passing algorithms(MPA)for orthogonal frequency division multiple access(OFDMA)systems.The channel estimation and symbol detection leverage the framework of expectation propagation(EP)and belief propagation(BP)with the aid of Gaussian approximation,respectively.Furthermore,to reduce the computation complexity involved in channel estimation,the matrix inversion is transformed into a series of diagonal matrix inversions through the Sherman-Morrison formula.Simulation experiments show that the proposed algorithm can reduce the pilot overhead by about 50%,compared with the traditional linear minimum mean square error(LMMSE)algorithm,and can approach to the bit error rate(BER)performance bound of perfectly known channel state information within 0.1 dB.
基金supported by the National Natural Science Foundation of China (Grant No. 62022019)
文摘An asynchronous transmission scenario for non-orthogonal multiple access(NOMA)user signals with arbitrary phase offset is investigated in this paper.To improve the system performance in the user power-balanced conditions,we adopt a synthetic detection method at the receiver,i.e.,the jointly optimal maximal likelihood detection aided triangular successive interference cancellation(JO ML-TSIC)method.Analytical bit error rate(BER)solutions are obtained for a two-user case with the optimal,intentional onehalf symbol period time delay implemented between the user signals.Furthermore,closed-form BER solutions for the case using the triangular successive interference cancellation(TSIC)detection method are also derived for comparisons.Numerical results show that the JO ML-TSIC receiver for the asynchronous system outperforms the TSIC receiver as well as the synchronous successive interference cancellation(SIC)receiver in all the conditions concerned.The results also show that the superiority of the JO ML-TSIC receiver is strengthened when the signals experience flat Rayleigh fading channels compared to the TSIC and the synchronous SIC receivers.
基金support from National Natural Science Foundation of China (Grant No. 61622110)
文摘With the rapid development of smart devices and mobile networks,multimedia services will dominate most of data traffic in 4G/5G networks.Applications -such as conversational videos,online multimedia sharing,remote education,etc.have gained their popularity and will become more ubiquitous among customers.Tra-
基金financial support from the Development Program of China(2018YFA0701601 and 2020YFB1804800)the National Natural Science Foundation of China(61922050)the Fundamental Research Project of Beijing National Research Center for Information Science and Technology(BNR2022RC02004)。
文摘The history of wireless communications can be divided into two eras.The first was a discovery-inspired era,initiated by the great physicist Maxwell’s discovery of the classical theory of electromagnetism,while the second was a technology-driven era that began with Marconi’s creation of the first practical world-wide radio-based wireless telegraph system,Shannon’s information theory,and the later invention of cellular mobile communications from the first generation(1G)to the fourth(4G).Nowadays,the fifth generation(5G)is regarded as a leading information and communication technology.
文摘This paper gives a definition of the Industrial Internet and expounds on the academic connotation of the future Industrial Internet.From this foundation,we outline the development and current status of the Industrial Internet in China and globally.Moreover,we detail the avant-garde paradigms encompassed within the National Natural Science Foundation of China(NSFC)’s“Future Industrial Internet Fundamental Theory and Key Technologies”research plan and its corresponding management strategies.This research initiative endeavors to enhance interdisciplinary collaborations,aiming for a synergistic alignment of industry,academia,research,and practical implementations.The primary focus of the research plan is on the pivotal scientific challenges inherent to the future industrial internet.It is poised to traverse the“first mile”,encompassing foundational research and pioneering innovations specific to the industrial internet,and seamlessly bridges to the“last mile”,ensuring the effective commercialization of scientific and technological breakthroughs into tangible industrial market applications.The anticipated contributions from this initiative are projected to solidify both the theoretical and practical scaffolding essential for the cultivation of a globally competitive industrial internet infrastructure in China.
文摘In the midst of the fourth industrial revolution,the convergence of the digital,physical,and biological realms is propelling industrial innovation to new heights.At the heart of this transformative era lies the Industrial Internet,a pivotal technology reshaping our industries.This powerful force establishes an all-encompassing network[1-2].
基金supported in part by the National Natural Science Foundation of China under Grants 62341104,62201085,62325108,and 62341131.
文摘Unmanned aerial vehicle (UAV)-based edge computing is an emerging technology that provides fast task processing for a wider area. To address the issues of limited computation resource of a single UAV and finite communication resource in multi-UAV networks, this paper joints consideration of task offloading and wireless channel allocation on a collaborative multi-UAV computing network, where a high altitude platform station (HAPS)is adopted as the relay device for communication between UAV clusters consisting of UAV cluster heads (ch-UAVs) and mission UAVs (m-UAVs). We propose an algorithm, jointing task offloading and wireless channel allocation to maximize the average service success rate (ASSR)of a period time. In particular,the simulated annealing(SA)algorithm with random perturbations is used for optimal channel allocation,aiming to reduce interference and minimize transmission delay.A multi-agent deep deterministic policy gradient (MADDPG) is proposed to get the best task offloading strategy. Simulation results demonstrate the effectiveness of the SA algorithm in channel allocation. Meanwhile,when jointly considering computation and channel resources,the proposed scheme effectively enhances the ASSR in comparison to other benchmark algorithms.
基金This work was supported in part by the National Key Research and Development Program of China under Grant 2020YFB1804800in part by the National Natural Science Foundation of China under Grant 61922050.
文摘Beam scheduling is one of the most important issues regarding data relay satellite systems,which can improve the utilization efficiency of limited system resources by programming beam allocation for relay missions.The ever-increasing relay missions create a substantial challenge for beam scheduling due to an increase in different mission demands.The cooperative usage of different beams further increases the complexity of this problem.Therefore,we develop a novel optimization method to solve the beam scheduling problem for the scenario of various mission demands in the data relay satellite system(DRSS).Based on the analysis of mission demands and resource features,we first construct a heterogeneous parallel machines scheduling model to formulate the beam scheduling problem in the DRSS.To solve this complicated model,we investigate the matching method between mission demands and beam resources,and introduce two concepts,the loose duration and the number of available beams,to make the matching process more effective.Then,the following three algorithms are proposed.Our first approach,the maximized completion probability algorithm(MCPA),applies a greedy strategy based on the new concepts to allocate beams for missions;and two improved versions of this algorithm are also presented,which employ the strategies of mission insertion optimization and mission sequence optimization,respectively.Our simulation results show that the proposed algorithms are superior to the existing algorithms in terms of the scheduled missions,the weight of scheduled missions,and the processing time,which significantly improves the performance of beam scheduling in the DRSS.
基金the National Natural Science Foundation of China(62001085)Sichuan Science and Technology Program(2021YFG0349)。
文摘Nowadays,cloud computing has been identified as new opportunities for migrating to the expected agility,reuse,and adaptive capabilities that can support the ever changing IT trends and requirements.Unfortunately,the rapid evolution of those technologies also comes with open issues such as security,privacy,integrity,quality of services,and their possible detrimental consequences.In this work,the concept of insurance is introduced to compensate the cloud computing customers when encountering those failures if service providers(SPs)have insurance purchased.Particularly,we consider the situation when the insurer is unable to see the system failure risk levels of the SPs,which is usually seen as an incomplete information market,in contrast with the optimal situation in a complete information market.First,an insurance-based cloud computing architecture is proposed to build a monetary credit system in which the cloud computing SP pays a premium for a certain coverage to the insurer.Subsequently,problem is formulated to solve the optimal insurance plan in complete and incomplete information markets,together with detail analysis of insurance policies in both cases are provided.Furthermore,simulation results show the properties of the two insurance plans and parameters that affect the design of the insurance plan.
基金the Key Project of the Key R&D Program(Nos.2018YFC1407200,2017YFC1405200)Ministry of Science and Technology,China,and partly supported by the new strategic industries development projects of Shenzhen City(No.JCYJ20170816151922176).
文摘The space-air-ground network architecture integrates satellite systems,aerial networks,and terrestrial networks,where the unmanned aerial vehicle(UAV)communication in the air segment has attracted particular interest and demonstrated tremendous potential in both military and civilian applications.Orthogonal frequency division multiplexing(OFDM)can be an effective solution to provide high rate and reliable transmission in UAV communication systems because of its high spectral efficiency and robustness against frequency selective fading.We herein focus our attention on two critical issues in our proposed UAV aided OFDM system,i.e.,timing synchronization and ranging.Moreover,extensive simulations are conducted for evaluation.Finally,we design a real-world field test for verifying the effectiveness of our proposed multi-UAV OFDM communication system.
基金supported by the National Natural Science Foundation of China(No.91338203).
文摘Thanks to the recent advances in SIS(Space Information Science)and increasingly mature technologies,network simulations have attracted much attention,which play vital roles in research on validation of the correctness of SIN’s(Space Information Network)solutions.In this paper,we constitute an architecture of a hardware-in-the-loop simulation system,where we use a server to act as a real satellite of SINs.Moreover,we model the channel of the satellite network relying on real cables and servers by referring to the Corazza model.Furthermore,based on the data of real weather events,we propose a coordinate mode for reducing LEO’s(Low Earth Orbit)communication delay and validate the efficiency of our proposed method on simulation platform by simplifying the problem to a shortest path problem.