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Mutual Information Maximization via Joint Power Allocation in Integrated Sensing and Communications System
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作者 Jia Zhu Junsheng Mu +1 位作者 Yuanhao Cui Xiaojun Jing 《China Communications》 SCIE CSCD 2024年第2期129-142,共14页
In this paper, we focus on the power allocation of Integrated Sensing and Communication(ISAC) with orthogonal frequency division multiplexing(OFDM) waveform. In order to improve the spectrum utilization efficiency in ... In this paper, we focus on the power allocation of Integrated Sensing and Communication(ISAC) with orthogonal frequency division multiplexing(OFDM) waveform. In order to improve the spectrum utilization efficiency in ISAC, we propose a design scheme based on spectrum sharing, that is,to maximize the mutual information(MI) of radar sensing while ensuring certain communication rate and transmission power constraints. In the proposed scheme, three cases are considered for the scattering off the target due to the communication signals,as negligible signal, beneficial signal, and interference signal to radar sensing, respectively, thus requiring three power allocation schemes. However,the corresponding power allocation schemes are nonconvex and their closed-form solutions are unavailable as a consequence. Motivated by this, alternating optimization(AO), sequence convex programming(SCP) and Lagrange multiplier are individually combined for three suboptimal solutions corresponding with three power allocation schemes. By combining the three algorithms, we transform the non-convex problem which is difficult to deal with into a convex problem which is easy to solve and obtain the suboptimal solution of the corresponding optimization problem. Numerical results show that, compared with the allocation results of the existing algorithms, the proposed joint design algorithm significantly improves the radar performance. 展开更多
关键词 COEXISTENCE communicationS multicarrier radar mutual information spectrum sharing
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System design and validation of Queqiao-2 lunar relay communication satellite
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作者 ZHANG Lihua XIONG Liang +11 位作者 SUN Ji CHEN Luojing XIAO Chuan ZHOU Wenyan WANG Yong LIU Wangwang GUAN Yifeng CHEN Tao YU Xiaochuan XU Jin CHEN Guohui CAO Xiaoping 《中国空间科学技术(中英文)》 CSCD 北大核心 2024年第5期23-39,共17页
In order to provide relay communication supports for future Chinese lunar exploration program,Queqiao-2 relay communication satellite was developed.Queqiao-2 can perform scientific observations with three kinds of sci... In order to provide relay communication supports for future Chinese lunar exploration program,Queqiao-2 relay communication satellite was developed.Queqiao-2 can perform scientific observations with three kinds of scientific instruments on board.The system design of Queqiao-2,including mission orbit and transfer orbit design,configuration and layout design,housekeeping and information flow design,power supply and distribution design,GNC and propulsion system design,communication links design,etc.,was accomplished through comprehensive tradeoff and evaluation on technical maturity,availability,schedule,cost,and so on.With a view to reducing development risk,both the platform and relay communication payloads were developed based on significant heritage from previous Queqiao relay satellite and other relevant spacecraft.Queqiao-2 features flexible system architecture to support multiple frequencies,modulations,data rates and software reconfigurations to meet new user requirements.Subsequent to a successful launch on March 20,2024,by means of 5 orbit maneuvers,Queqiao-2 was inserted into a highly elliptical frozen mission orbit around the moon with a 24h period on schedule.Following on-orbit tests and calibrations,Queqiao-2 has possessed the capacity to provide reliable relay communication services to multiple lunar exploration missions,as well as the capacity to perform scientific observations.Under the support of Queqiao-2,Chang′e-6 achieved its ambitious mission goal to collect and return samples from the moon′s mysterious far side.In the meanwhile,Queqiao-2 has also paved the way for the following Chinese lunar exploration missions including Chang′e-7 and Chang′e-8.The design life time of Queqiao-2 is more than 8 years.Benefit from flexibility and extensibility of relay communication system design,it is convenient to provide relay communication services for future lunar exploration missions of both China and other countries.In addition,innovative scientific observations would be performed during the period that no relay communication task is arranged.The system design of Queqiao-2 reflects the development philosophy of technical innovations and inheritance integration.Based on highly flexible and extensible system architecture,multiple and concurrent relay communication mission requirements can be met.It can provide strong supports for future lunar exploration missions.Successful launching,orbit entering and on-orbit tests of Queqiao-2 verified the correct design principle and versatility.By means of Queqiao-2,more innovative scientific outcomes are anticipated and lunar exploration activities can be facilitated. 展开更多
关键词 lunar explorations relay communication Queqiao system design TEST VALIDATION
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Age of Information for Short-Packet Covert Communication with Time Modulated Retrodirective Array
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作者 Ma Yue Ma Ruiqian +4 位作者 Lin Zhi Yang Weiwei Cai Yueming Miao Chen Wu Wen 《China Communications》 SCIE CSCD 2024年第4期23-37,共15页
In this paper,the covert age of information(CAoI),which characterizes the timeliness and covertness performance of communication,is first investigated in the short-packet covert communication with time modulated retro... In this paper,the covert age of information(CAoI),which characterizes the timeliness and covertness performance of communication,is first investigated in the short-packet covert communication with time modulated retrodirective array(TMRDA).Specifically,the TMRDA is designed to maximize the antenna gain in the target direction while the side lobe is sufficiently suppressed.On this basis,the covertness constraint and CAoI are derived in closed form.To facilitate the covert transmission design,the transmit power and block-length are jointly optimized to minimize the CAoI,which demonstrates the trade-off between covertness and timelessness.Our results illustrate that there exists an optimal block-length that yields the minimum CAoI,and the presented optimization results can achieve enhanced performance compared with the fixed block-length case.Additionally,we observe that smaller beam pointing error at Bob leads to improvements in CAoI. 展开更多
关键词 age of information covert communication retrodirective array time modulation
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Design and Analysis of Traffic Information Transmission System Based on Visible Light Communication 被引量:1
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作者 Wei Wang Hui-Fang Liu +2 位作者 Ning Wang Zhao Hui Chi Song 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第5期57-61,共5页
Visible Light Communication( VLC) based on LED is a new wireless communication technology with high response rate and good modulation characteristics in the wavelengths of 380- 780 nm. Compared with conventional metho... Visible Light Communication( VLC) based on LED is a new wireless communication technology with high response rate and good modulation characteristics in the wavelengths of 380- 780 nm. Compared with conventional methods,the waveband of VLC is harmless to human and safe to communication because of no magnetism radiation. An audio information transmission system using LED traffic lights is presented based on VLC technology. The system is consisted of transmitting terminal,receiving terminal and communication channel. Some experiments were made under real communication environment. The experimental results showed that the traffic information transmission system works steadily with good communication quality and achieves the purpose of transmitting audio information through LED traffic lights,with a data transfer rate up to 250 kbps over a distance of 5 meters. 展开更多
关键词 LED Traffic Lights Visible Light communication(VLC) Audio information Transmission Intelligent Transport System(ITS)
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Application and Challenge of Edge Computing Based on 5G Communication in Information and Communication Systems
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作者 Zhengwei Li Kan Cao 《Journal of Electronic Research and Application》 2024年第6期39-45,共7页
With the rapid development of information technology,5G communication technology has gradually entered real life,among which the application of edge computing is particularly significant in the information and communi... With the rapid development of information technology,5G communication technology has gradually entered real life,among which the application of edge computing is particularly significant in the information and communication system field.This paper focuses on using edge computing based on 5G communication in information and communication systems.First,the study analyzes the importance of combining edge computing technology with 5G communication technology,and its advantages,such as high efficiency and low latency in processing large amounts of data.The study then explores multiple application scenarios of edge computing in information and communication systems,such as integrated use in the Internet of Things,intelligent transportation,telemedicine and Industry 4.0.The research method is mainly based on theoretical analysis and experimental verification,combined with the characteristics of the 5G network to optimize the edge computing model and test the performance of edge computing in different scenarios through experimental simulation.The results show that edge computing significantly improves the data processing capacity and response speed of ICS in a 5G environment.However,there are also a series of challenges in practical application,including data security and privacy protection,the complexity of resource management and allocation,and the guarantee of quality of service(QoS).Through the case analysis and problem analysis,the paper puts forward the corresponding solution strategies,such as strengthening the data security protocol,introducing the intelligent resource scheduling system and establishing a multi-dimensional service quality monitoring mechanism.Finally,this study points out that the deep integration of edge computing and 5G communication will continue to promote the innovative development of information and communication systems,which has a far-reaching impact and important practical significance for promoting the transformation and upgrading in the field of information technology. 展开更多
关键词 5G communication Edge computing information communication system Data security Service quality
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Research on Information Architecture Design of Short-Form Video Social Platforms Based on Cognitive Psychology
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作者 Zhengyang Liu Albert Young Choi 《Psychology Research》 2024年第1期1-13,共13页
This study investigates how cognitive psychology principles can be integrated into the information architecture design of short-form video platforms,like TikTok,to enhance user experience,engagement,and sharing.Using ... This study investigates how cognitive psychology principles can be integrated into the information architecture design of short-form video platforms,like TikTok,to enhance user experience,engagement,and sharing.Using a questionnaire,it explores TikTok users’habits and preferences,highlighting how social media fatigue(SMF)impacts their interaction with the platform.The paper offers strategies to optimize TikTok’s design.It suggests refining the organizational system using principles like chunking,schema theory,and working memory capacity.Additionally,it proposes incorporating shopping features within TikTok’s interface to personalize product suggestions and enable monetization for influencers and content creators.Furthermore,the study underlines the need to consider gender differences and user preferences in improving TikTok’s sharing features,recommending streamlined and customizable sharing options,collaborative sharing,and a system to acknowledge sharing milestones.Aiming to strengthen social connections and increase sharing likelihood,this research provides insights into enhancing information architecture for short-form video platforms,contributing to their growth and success. 展开更多
关键词 information architecture design short-form video social cognitive psychology user experience
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The Overall Design of Land-Use Information System Based on GIS 被引量:1
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作者 Zhang Guangyu Liu Yongqing(Institute of System Engineering, SCUT, Guangzhou 510641, P. R. China)(Received December 1, 1997) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1999年第1期11-16,共6页
The land-use information system (LUIS) is a special geographical information system developed under the support of the geographical information system (GIS). It effectively combines the quantitative analysis with spac... The land-use information system (LUIS) is a special geographical information system developed under the support of the geographical information system (GIS). It effectively combines the quantitative analysis with space analysis, mixes the feature of the land-use data and figure de scription, achieves the mutual transfer of the data and figure, and provides some effective methods for the quantitative research and space analysis. The targets, methods and procedures of the overall design of LUIS and its structure function and characteristic are presented in this paper. It pro vides the guide and references for developing the special GIS suitable for the demand of land-use management. 展开更多
关键词 Land-use information system Geographical information system Overall design.
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Integrating Universal Design Standards and Building Information Modeling at the Conceptual Design Stage of Buildings
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作者 Vafa Rostamiasl Ahmad Jrade 《Open Journal of Civil Engineering》 CAS 2022年第4期492-523,共32页
A projection of the Canadian population shows that in 2024 one in five Canadians will be over 65 years old. This shift forces designers to consider the entire lifetime of occupants during the design of new buildings. ... A projection of the Canadian population shows that in 2024 one in five Canadians will be over 65 years old. This shift forces designers to consider the entire lifetime of occupants during the design of new buildings. Universal Design (UD), which is a design that accommodates all people to the greatest extent possible and aging in place design that is deeply rooted in the principles of UD, aim to house people irrespective of their age, ability, and chronic health conditions. Building Information Modeling (BIM) significantly helps advance the development of the Architecture, Engineering, and Construction (AEC) industry in a more collaborative and automated way. Integrating BIM and UD allows designers to incorporate UD standards easily and efficiently at the conceptual design stage of buildings by using the functionalities and capabilities of BIM tools. Therefore, this study presents the development of an automated computer model to facilitate the adoption of UD standards and processes. The novelty highlighted in this model resides in the creation of an automated method that employs a newly created plug-in and databases to assist designers to incorporate UD standards at the conceptual stage in a timely and cost-effective manner. Furthermore, the study introduces the methodology consisting of collecting, categorizing, and storing data from various universal design and accessible design guidelines in the developed databases and developing new plug-ins in BIM tool to link the developed databases in order to automate the process of retrieving necessary information and components to help designers and owners select optimal design alternatives based on their predefined criteria. 展开更多
关键词 Building information Modeling (BIM) Universal design Accessible design Aging in Place Computer Integration and Automation
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Based on the visual communication design under the influence of the digital media research
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作者 ZHANG Ao 《International English Education Research》 2016年第4期84-85,共2页
The visual communication design is mainly ~om the perspective of people, heard with the help of media technology to convey the information to the design form of object. Visual communication design on people's behavio... The visual communication design is mainly ~om the perspective of people, heard with the help of media technology to convey the information to the design form of object. Visual communication design on people's behavior and lifestyle has obvious effect, due to the widespread attention of people. The development of modem social economy and science and technology has changed the way of information extraction, requires designers must be under the influence of digital media technology with more diverse forms of design of visual communication design research. In this paper, on the basis of the brief analysis of the visual communication characteristics and under the influence of digital media design language features, and studies the influence of digital media under the trend of the development of visual communication design several opinions are put forward. 展开更多
关键词 digital media Visual communication design Visual communication characteristics
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The Preliminary Design and Implement of Plant Digital Information Retrieval System 被引量:3
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作者 樊永军 闫伟 +2 位作者 王黎元 杨秀丽 刘学威 《Agricultural Science & Technology》 CAS 2011年第5期751-755,共5页
[Objective] The aim was to set up a plant digital information retrieval system.[Method] Plant digital information retrieval system was designed by combining with Microsoft Visual Basic 6.0 Enterprise Edition database ... [Objective] The aim was to set up a plant digital information retrieval system.[Method] Plant digital information retrieval system was designed by combining with Microsoft Visual Basic 6.0 Enterprise Edition database management system and Structure Query Language.[Result] The system realized electronic management and retrieval of local plant information.The key words of retrieval included family,genus,formal name,Chinese name,Latin,morphological characteristics,habitat,collection people,collection places,and protect class and so on.[Conclusion] It provided reference for these problems of species identification and digital management of herbarium. 展开更多
关键词 Plant digital information retrieval system DATABASE design and implement
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Mobile Jammer-Aided Secure UAV Communications via Trajectory Design and Power Control 被引量:13
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作者 An Li Wenjing Zhang 《China Communications》 SCIE CSCD 2018年第8期141-151,共11页
To further promote the achievable average secrecy rate for UAV-ground communications, a UAV-aided mobile jamming strategy was proposed in this paper. Specifically, an additional cooperative UAV is employed as a mobile... To further promote the achievable average secrecy rate for UAV-ground communications, a UAV-aided mobile jamming strategy was proposed in this paper. Specifically, an additional cooperative UAV is employed as a mobile jammer to transmit the jamming signal to help keep the source UAV closer to the ground destination, thus establishing more favorable legitimate link and enhancing the secrecy performance. We aimed to maximize the achievable secrecy rate by jointly optimizing the trajectories and transmit power of both source UAV and jammer UAV. To solve the considered non-convex optimization problem, we presented a block coordinate descent based iterative algorithm to address a sequence of approximated convex problems for the optimized parameter block by block to find a local optimal solution. Numerical results verify that the proposed algorithm can achieve significant secrecy rate gain compared to all the benchmark schemes. 展开更多
关键词 physical layer security UAV-ground communications mobile jammer-aided trajectory design power control
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New Hybrid AD Methodology for Minimizing the Total Amount of Information Content:A Case Study of Rehabilitation Robot Design 被引量:4
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作者 Tao Yang Xueshan Gao Fuquan Dai 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第6期177-186,共10页
Converting customer needs into specific forms and providing consumers with services are crucial in product design.Currently,conversion is no longer difficult due to the development of modern technology,and various mea... Converting customer needs into specific forms and providing consumers with services are crucial in product design.Currently,conversion is no longer difficult due to the development of modern technology,and various measures can be applied for product realization,thus increasing the complexity of analysis and evaluation in the design process.The focus of the design process has thus shifted from problem solving to minimizing the total amount of information content.This paper presents a New Hybrid Axiomatic Design(AD)Methodology based on iteratively matching and merging design parameters that meet the independence axiom and attribute constraints by applying trimming technology,the ideal final results,and technology evolution theory.The proposed method minimizes the total amount of information content and improves the design quality.Finally,a case study of a rehabilitation robot design for hemiplegic patients is presented.The results indicate that the iterative matching and merging of related attributes can minimize the total amount of information content,reduce the cost,and improve design efficiency.Additionally,evolutionary technology prediction can ensure product novelty and improve market competitiveness.The methodology provides an excellent way to design a new(or improved)product. 展开更多
关键词 Axiomatic design Amount of information content TRIMMING Rehabilitation robot
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Energy-Efficient UAV Trajectory Design for Backscatter Communication: A Deep Reinforcement Learning Approach 被引量:5
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作者 Yiwen Nie Junhui Zhao +2 位作者 Jun Liu Jing Jiang Ruijin Ding 《China Communications》 SCIE CSCD 2020年第10期129-141,共13页
Recently,backscatter communication(BC)has been introduced as a green paradigm for Internet of Things(IoT).Meanwhile,unmanned aerial vehicles(UAVs)can serve as aerial base stations(BSs)to enhance the performance of BC ... Recently,backscatter communication(BC)has been introduced as a green paradigm for Internet of Things(IoT).Meanwhile,unmanned aerial vehicles(UAVs)can serve as aerial base stations(BSs)to enhance the performance of BC system thanks to their high mobility and flexibility.In this paper,we investigate the problem of energy efficiency(EE)for an energy-limited backscatter communication(BC)network,where backscatter devices(BDs)on the ground harvest energy from the wireless signal of a flying rotary-wing quadrotor.Specifically,we first reformulate the EE optimization problem as a Markov decision process(MDP)and then propose a deep reinforcement learning(DRL)algorithm to design the UAV trajectory with the constraints of the BD scheduling,the power reflection coefficients,the transmission power,and the fairness among BDs.Simulation results show the proposed DRL algorithm achieves close-to-optimal performance and significant EE gains compared to the benchmark schemes. 展开更多
关键词 unmanned aerial vehicle(UAV) trajectory design backscatter communication deep reinforcement learning ENERGY-EFFICIENT
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Robust Trajectory and Communication Design for Angle-Constrained Multi-UAV Communications in the Presence of Jammers 被引量:3
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作者 Yufang Gao Yang Wu +3 位作者 Zhichao Cui Wendong Yang Guojie Hu Shiming Xu 《China Communications》 SCIE CSCD 2022年第2期131-147,共17页
This paper studies a multi-unmanned aerial vehicle(UAV)enabled wireless communication system,where multiple UAVs are employed to communicate with a group of ground terminals(GTs)in the presence of potential jammers.We... This paper studies a multi-unmanned aerial vehicle(UAV)enabled wireless communication system,where multiple UAVs are employed to communicate with a group of ground terminals(GTs)in the presence of potential jammers.We aim to maximize the throughput overall GTs by jointly optimizing the UAVs’trajectory,the GTs’scheduling and power allocation.Unlike most prior studies,we consider the UAVs’turning and climbing angle constraints,the UAVs’three-dimensional(3D)trajectory constraints,minimum UAV-to-UAV(U2U)distance constraint,and the GTs’transmit power requirements.However,the formulated problem is a mixed-integer non-convex problem and is intractable to work it out with conventional optimization methods.To tackle this difficulty,we propose an efficient robust iterative algorithm to decompose the original problem be three sub-problems and acquire the suboptimal solution via utilizing the block coordinate descent(BCD)method,successive convex approximation(SCA)technique,and S-procedure.Extensive simulation results show that our proposed robust iterative algorithm offers a substantial gain in the system performance compared with the benchmark algorithms. 展开更多
关键词 ANTI-JAMMING angle constraints robust design multi-UAV communications 3D trajectory optimization
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Secure Beamforming Design for SWIPT in Cooperative D2D Communications 被引量:5
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作者 Li Jiang Cheng Qin +1 位作者 Xixi Zhang Hui Tian 《China Communications》 SCIE CSCD 2017年第1期20-33,共14页
In device-to-device(D2D) communications, device terminal relaying makes it possible for devices in a network to function as transmission relays for each other to enhance the spectral efficiency. In this paper we consi... In device-to-device(D2D) communications, device terminal relaying makes it possible for devices in a network to function as transmission relays for each other to enhance the spectral efficiency. In this paper we consider a cooperative D2D communication system with simultaneous wireless information and power transfer(SWIPT). The cooperative D2D communication scheme allows two nearby devices to communicate with each other in the licensed cellular bandwidth by assigning D2D transmitters as half-duplex(HD) relay to assists cellular downlink transmissions. In particular, we focus on secure information transmission for the cellular users when the idle D2D users are the potential eavesdroppers. We aim to design secure beamforming schemes to maximize the D2D users data rate while guaranteeing the secrecy rate requirements of the cellular users and the minimum required amounts of power transferred to the idle D2D users. To solve this non-convex problem, a semi-definite programming relaxation(SDR) approach is adopted to obtain the optimal solution. Furthermore, we propose two suboptimal secure beamforming schemes with low computational complexity for providing secure communication and efficient energy transfer. Simulation results demonstrate the superiority of our proposed scheme. 展开更多
关键词 device-to-device(D2D) communications half-duplex relaying physical layer security secure beamforming simultaneous wireless information and power transfer
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Precoder Design and Impulsive Noise Mitigation Scheme for Industrial Wireless Communications 被引量:2
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作者 Yanjing Sun Xinyan Li +3 位作者 Jiasi Zhou Ruirui Chen BowenWang Yanfen Wang 《China Communications》 SCIE CSCD 2021年第4期182-197,共16页
In industrial wireless scenarios,the impulsive noise(IN)incurred by machine running or operation causes a serious influence on the powerlimited industrial wireless communications.It is challenging to ensure efficient ... In industrial wireless scenarios,the impulsive noise(IN)incurred by machine running or operation causes a serious influence on the powerlimited industrial wireless communications.It is challenging to ensure efficient and reliable transmission with quality of service(QoS)guarantee for machinetype communication devices(MTCDs).Considering the IN in the industrial process,this paper establishes the multiuser multiple-input single-output(MU-MISO)orthogonal frequency division multiplexing(OFDM)system model,which combines transmitter and receiver design.Two precoding schemes are designed to improve communication effectiveness at the transmitter.More specifically,the precoder design scheme which combines semi-definite relaxation(SDR)with difference-of-two-convex-function(D.C.)iterative algorithm,is developed by utilizing the Dinkelbach method to improve the system effectiveness.To decrease the computational complexity,we devise the quadratic-based fractional programming(QFP)algorithm,which decouples the variables by using a quadratic transform method.On this basis,the IN mitigation scheme is studied to reduce the system error rate(SER)at the receiver.With the goal of improving the reliability of industrial wireless communications,we propose a hybrid nonlinear IN mitigation(HNINM)scheme and then derive its closed-form expression of SER.The simulation results show that the proposed QFP algorithm achieves superior performance while the HNINM scheme decreases the SER of industrial wireless communications. 展开更多
关键词 Industrial wireless communications precoder design impulsive noise mitigation
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Forecasting promising technology using analysis of patent information:Focused on next generation mobile communications 被引量:8
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作者 CHOI Seung-Wook YOU Yen-Yoo NA Kwan-Sik 《Journal of Central South University》 SCIE EI CAS 2014年第11期4303-4310,共8页
In order to forecast promising technologies in the field of next generation mobile communication, various patent indicators were analyzed such as citation per patent, patent family information, patent share, increase ... In order to forecast promising technologies in the field of next generation mobile communication, various patent indicators were analyzed such as citation per patent, patent family information, patent share, increase rate, and patent activity. These indicators were quantified into several indexes and then integrated into an evaluation score to provide promising technologies. As a result of the suggested patent analysis, four technologies out of twenty two in details classification were selected, which showed outstanding technology competitiveness, high patent share and increasing rates as well as high recent-patent-ratios and triad-patent-family-ratios. Each of the selected technologies scored more than 10 points in total, and the following four technologies were suggested as promising ones in the field of next generation mobile communication: 1) 3GPP based mobile communication, 2) beyond 4G mobile communication, 3) IEEE 802.16 based mobile communication, which are in medium classification of broadband mobile communication system, and 4) testing/certification system of mobile communication, which is in medium classification of mobile communication testing/certification system. 展开更多
关键词 next generation mobile communication promising technology forecasting patent information patent analysis patent indicators
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Construction of Agricultural Information Service System in China——under the Eyeshot of Communication Science 被引量:4
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作者 邓涛 《Agricultural Science & Technology》 CAS 2010年第5期171-173,共3页
The paper aims to study the current communication condition,configuration,characteristic and regulation of Chinese agricultural information in terms of the eyeshot of communication studies,and provide reference to bui... The paper aims to study the current communication condition,configuration,characteristic and regulation of Chinese agricultural information in terms of the eyeshot of communication studies,and provide reference to build Chinese agricultural information service system based on the analysis of their advantages and disadvantages. 展开更多
关键词 communication studies Agriculture information service system
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A New Codebook Design Scheme for Fast Beam Searching in Millimeter-Wave Communications 被引量:1
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作者 ZOU Weixia GUO Chao +2 位作者 DU Guanglong WANG Zhenyu GAO Ying 《China Communications》 SCIE CSCD 2014年第6期12-22,共11页
To overcome imperfection of exhaustive based beam searching scheme in IEEE 802.15.3c and IEEE 802.11 ad and accelerate the beam training process, combined with the fast beam searching algorithm previously proposed, th... To overcome imperfection of exhaustive based beam searching scheme in IEEE 802.15.3c and IEEE 802.11 ad and accelerate the beam training process, combined with the fast beam searching algorithm previously proposed, this paper proposed a beam codebook design scheme for phased array to not only satisfy the fast beam searching algorithm's demand, but also make good use of the advantage of the searching algorithm. The simulation results prove that the proposed scheme not only performs well on flexibility and searching time complexity, but also has high success ratio. 展开更多
关键词 wireless communication 60GHz phased array BEAM-FORMING beam searching beam codebook design
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Information Theory of Cartography:An Information-theoretic Framework for Cartographic Communication 被引量:11
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作者 Zhilin LI Peichao GAO Zhu XU 《Journal of Geodesy and Geoinformation Science》 2021年第1期1-16,共16页
Map is one of the communication means created by human being.Cartographers have been making efforts on the comparison of maps to natural languages so as to establish a"cartographic language"or"map langu... Map is one of the communication means created by human being.Cartographers have been making efforts on the comparison of maps to natural languages so as to establish a"cartographic language"or"map language".One of such efforts is to adopt the Shannon’s Information Theory originated in digital communication into cartography so as to establish an entropy-based cartographic communication theory.However,success has been very limited although research work had started as early as the mid-1960 s.It is then found that the bottleneck problem was the lack of appropriate measures for the spatial(configurational)information of(graphic and image)maps,as the classic Shannon entropy is only capable of characterizing statistical information but fails to capture the configurational information of(graphic and image)maps.Fortunately,after over 40-year development,some bottleneck problems have been solved.More precisely,generalized Shannon entropies for metric and thematic information of(graphic)maps have been developed and the first feasible solution for computing the Boltzmann entropy of image maps has been invented,which is capable of measuring the spatial information of not only numerical images but also categorical maps.With such progress,it is now feasible to build the"Information Theory of Cartography".In this paper,a framework for such a theory is proposed and some key issues are identified.For these issues,some have already been tackled while others still need efforts.As a result,a research agenda is set for future action.After all these issues are tackled,the theory will become matured so as to become a theoretic basis of cartography.It is expected that the Information Theory of Cartography will play an increasingly important role in the discipline of cartography because more and more researchers have advocated that information is more fundamental than matter and energy. 展开更多
关键词 information Theory of Cartography cartographic communication spatial information of maps generalized Shannon Entropy Boltzmann entropy
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