In this article,the phenomenon of“information space”and its methods of study,its types,elementary structure and qualitative characteristics are discussed,the author’s definition of the concept of“information”is g...In this article,the phenomenon of“information space”and its methods of study,its types,elementary structure and qualitative characteristics are discussed,the author’s definition of the concept of“information”is given,the structure of the information process,and the phases,which are the basis for the evolution of the information space and the universe of human activity,are considered.展开更多
It is a challenge to investigate the interrelationship between the geometric structure and performance of sensor networks due to the increasingly complex and diverse architecture of them.This paper presents two new fo...It is a challenge to investigate the interrelationship between the geometric structure and performance of sensor networks due to the increasingly complex and diverse architecture of them.This paper presents two new formulations for the information space of sensor networks,including Lagrangian and energy–momentum tensor,which are expected to integrate sensor networks target tracking and performance evaluation from a unified perspective.The proposed method presents two geometric objects to represent the dynamic state and manifold structure of the information space of sensor networks.Based on that,the authors conduct the property analysis and target tracking of sensor networks.To the best of our knowledge,it is the first time to investigate and analyze the information energy-momentum tensor of sensor networks and evaluate the performance of sensor networks in the context of target tracking.Simulations and examples confirm the competitive performance of the proposed method.展开更多
The features of information technology （IT） are discussed first. On this basis, the features of space information technology （SIT） are presented and SIT is elaborated in five categories. The popularization of SIT ...The features of information technology （IT） are discussed first. On this basis, the features of space information technology （SIT） are presented and SIT is elaborated in five categories. The popularization of SIT is an informatization process and will promote the industrialization of national economy and the modernization of industry such as agriculture. The necessity of the synthetical application of SIT is studied emphatically, and the development trend of SIT is discussed.展开更多
Ongoing research is described that is focused upon modelling the space base information network and simulating its behaviours： simulation of spaced based communications and networking project. Its objective is to dem...Ongoing research is described that is focused upon modelling the space base information network and simulating its behaviours： simulation of spaced based communications and networking project. Its objective is to demonstrate the feasibility of producing a tool that can provide a performance evaluation of various eonstellation access techniques and routing policies. The architecture and design of the simulation system are explored. The algorithm of data routing and instrument scheduling in this project is described. Besides these, the key methodologies of simulating the inter-satellite link features in the data transmissions are also discussed. The performance of both instrument scheduling algorithm and routing schemes is evaluated and analyzed through extensive simulations under a typical scenario.展开更多
(November 2009 Beijing, China) STUDY THE TECHNOLOGY OF SPACE INFORMATION EXPLORE THE FUTURE OF HUMAN KINDSponsored by China Academy of Space Technology (CAST) Co-sponsored by The Second Academy of China Aerospace Scie...(November 2009 Beijing, China) STUDY THE TECHNOLOGY OF SPACE INFORMATION EXPLORE THE FUTURE OF HUMAN KINDSponsored by China Academy of Space Technology (CAST) Co-sponsored by The Second Academy of China Aerospace Science and展开更多
Commercial behavior in towns and cities is mainly divided into formal and informal behavior.Rapid urbanization has enabled formal commerce to develop more and more perfectly in towns,basically meeting the living needs...Commercial behavior in towns and cities is mainly divided into formal and informal behavior.Rapid urbanization has enabled formal commerce to develop more and more perfectly in towns,basically meeting the living needs of residents. However, because of problems such as urban history and management mechanism, informal commercial behavior formed by floating stallholders and other employed people is widespread in towns. Due to the characteristics of instability, flexibility and richness,informal commerce has gradually developed into an important business to attract residents and tourists. In this paper, the general characteristics of informal commercial behavior in towns, the characteristics of the urban public space bearing this kind of commerce, and residents' demand for informal commercial space were summarized, and then the optimization strategies of this kind of public space were put forward to help towns make full use of their scattered space, create diversified commercial places, and add vitality to urban space while providing residents and tourists with daily life needs and convenience.展开更多
A novel practical codebook-precoding multiple-input multiple-output（MIMO） system based on signal space diversity（SSD） with the minimum mean squared error（MMSE）receiver is proposed.This scheme utilizes rotation m...A novel practical codebook-precoding multiple-input multiple-output（MIMO） system based on signal space diversity（SSD） with the minimum mean squared error（MMSE）receiver is proposed.This scheme utilizes rotation modulation and space-time-frequency component interleaving.A novel precoding matrix selection criterion to maximize the average signal to interference plus noise ratio（SINR） is also put forward for the proposed scheme,which has a larger average mutual information（AMI）.Based on the AMI- maximization criterion,the optimal rotation angles for the proposed system are also investigated.The new scheme can make full use of space-time-frequency diversity and signal space diversity,and exhibit high spectral efficiency and high reliability in fading channels.Simulation results show that the proposed scheme greatly outperforms the conventional bit- interleaved coded modulation（BICM） MIMO-orthogonal frequency division multiplexing（OFDM） scheme without SSD,which is up to4.5 dB signal-to-noise ratio（SNR） gain.展开更多
Space information network is used for real time acquiring, transmitting and processing the space information on the space platform, which provides significant communication services for communication, navigation posit...Space information network is used for real time acquiring, transmitting and processing the space information on the space platform, which provides significant communication services for communication, navigation positioning and science exploration. In this paper, the architecture of Software Defined Space Optical Network (SDSON) based on cloud platform is designed by means of Software Defined Optical Network (SDON) and cloud services. The new architecture combining centralized and distributed management-control mechanism is a multi-layer and multi-domain architecture with powerful computing and storage ability. Moreover, reliable service and unreliable service communication models employed in the space information network are proposed considering the characteristic of Disruption/Delay Tolerant Network (DTN). Finally, the functional verification and demonstration are performed on our optical experimental network platform.展开更多
文摘In this article,the phenomenon of“information space”and its methods of study,its types,elementary structure and qualitative characteristics are discussed,the author’s definition of the concept of“information”is given,the structure of the information process,and the phases,which are the basis for the evolution of the information space and the universe of human activity,are considered.
基金supported by the National Natural Science Foundation of China(No.51875014)。
文摘It is a challenge to investigate the interrelationship between the geometric structure and performance of sensor networks due to the increasingly complex and diverse architecture of them.This paper presents two new formulations for the information space of sensor networks,including Lagrangian and energy–momentum tensor,which are expected to integrate sensor networks target tracking and performance evaluation from a unified perspective.The proposed method presents two geometric objects to represent the dynamic state and manifold structure of the information space of sensor networks.Based on that,the authors conduct the property analysis and target tracking of sensor networks.To the best of our knowledge,it is the first time to investigate and analyze the information energy-momentum tensor of sensor networks and evaluate the performance of sensor networks in the context of target tracking.Simulations and examples confirm the competitive performance of the proposed method.
文摘The features of information technology （IT） are discussed first. On this basis, the features of space information technology （SIT） are presented and SIT is elaborated in five categories. The popularization of SIT is an informatization process and will promote the industrialization of national economy and the modernization of industry such as agriculture. The necessity of the synthetical application of SIT is studied emphatically, and the development trend of SIT is discussed.
基金This project was supported by the National "863" High-Tech Research and Development Program of China(2002AA7170)
文摘Ongoing research is described that is focused upon modelling the space base information network and simulating its behaviours： simulation of spaced based communications and networking project. Its objective is to demonstrate the feasibility of producing a tool that can provide a performance evaluation of various eonstellation access techniques and routing policies. The architecture and design of the simulation system are explored. The algorithm of data routing and instrument scheduling in this project is described. Besides these, the key methodologies of simulating the inter-satellite link features in the data transmissions are also discussed. The performance of both instrument scheduling algorithm and routing schemes is evaluated and analyzed through extensive simulations under a typical scenario.
文摘(November 2009 Beijing, China) STUDY THE TECHNOLOGY OF SPACE INFORMATION EXPLORE THE FUTURE OF HUMAN KINDSponsored by China Academy of Space Technology (CAST) Co-sponsored by The Second Academy of China Aerospace Science and
基金Supported by National Natural Science Foundation of China (51768026)Humanities and Social Sciences Project of Colleges and Universities in Jiangxi Province,China (YC2021-S225)。
文摘Commercial behavior in towns and cities is mainly divided into formal and informal behavior.Rapid urbanization has enabled formal commerce to develop more and more perfectly in towns,basically meeting the living needs of residents. However, because of problems such as urban history and management mechanism, informal commercial behavior formed by floating stallholders and other employed people is widespread in towns. Due to the characteristics of instability, flexibility and richness,informal commerce has gradually developed into an important business to attract residents and tourists. In this paper, the general characteristics of informal commercial behavior in towns, the characteristics of the urban public space bearing this kind of commerce, and residents' demand for informal commercial space were summarized, and then the optimization strategies of this kind of public space were put forward to help towns make full use of their scattered space, create diversified commercial places, and add vitality to urban space while providing residents and tourists with daily life needs and convenience.
基金supported by the National Natural Science Foundation of China(61171101)the Fundamental Research Funds for the Central Universitiesthe 2014 Doctorial Innovation Fund of Beijing University of Posts and Telecommunications(CX201426)
文摘A novel practical codebook-precoding multiple-input multiple-output（MIMO） system based on signal space diversity（SSD） with the minimum mean squared error（MMSE）receiver is proposed.This scheme utilizes rotation modulation and space-time-frequency component interleaving.A novel precoding matrix selection criterion to maximize the average signal to interference plus noise ratio（SINR） is also put forward for the proposed scheme,which has a larger average mutual information（AMI）.Based on the AMI- maximization criterion,the optimal rotation angles for the proposed system are also investigated.The new scheme can make full use of space-time-frequency diversity and signal space diversity,and exhibit high spectral efficiency and high reliability in fading channels.Simulation results show that the proposed scheme greatly outperforms the conventional bit- interleaved coded modulation（BICM） MIMO-orthogonal frequency division multiplexing（OFDM） scheme without SSD,which is up to4.5 dB signal-to-noise ratio（SNR） gain.
文摘Space information network is used for real time acquiring, transmitting and processing the space information on the space platform, which provides significant communication services for communication, navigation positioning and science exploration. In this paper, the architecture of Software Defined Space Optical Network (SDSON) based on cloud platform is designed by means of Software Defined Optical Network (SDON) and cloud services. The new architecture combining centralized and distributed management-control mechanism is a multi-layer and multi-domain architecture with powerful computing and storage ability. Moreover, reliable service and unreliable service communication models employed in the space information network are proposed considering the characteristic of Disruption/Delay Tolerant Network (DTN). Finally, the functional verification and demonstration are performed on our optical experimental network platform.
