检索结果-南通市图书馆

Reinforcement Learning Based dynamic spectrum access in Cognitive Internet of Vehicles

在线全文

学校读者我要写书评

暂无评论

China Communications 2021年第7期18卷 58-68页

作者： Xin Liu Can Sun Mu Zhou Bin Lin Yuto Lim School of Information and Communication Engineering Dalian University of TechnologyDalian 116024China State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an 710071China Chongqing Key Lab of Mobile Communications Technology Chongqing University of Posts and TelecommunicationsChongqing 400065China Department of Communication Engineering Institute of Information Science TechnologyDalian Maritime UniversityDalian 116026China School of Information Science Japan Advanced Institute of Science and TechnologyIshikawa 923-1292Japan

Cognitive Internet of Vehicles(CIoV)can improve spectrum utilization by accessing the spectrum licensed to primary user(PU)under the premise of not disturbing the PU’s ***,the traditional static spectrum access makes the CIoV unable to adapt to the various spectrum *** this paper,a reinforcement learning based dynamic spectrum access scheme is proposed to improve the transmission performance of the CIoV in the licensed spectrum,and avoid causing harmful interference to the *** frame structure of the CIoV is separated into sensing period and access period,whereby the CIoV can optimize the transmission parameters in the access period according to the spectrum decisions in the sensing *** both detection probability and false alarm probability,a Q-learning based spectrum access algorithm is proposed for the CIoV to intelligently select the optimal channel,bandwidth and transmit power under the dynamic spectrum states and various spectrum sensing *** simulations have shown that compared with the traditional non-learning spectrum access algorithm,the proposed Q-learning algorithm can effectively improve the spectral efficiency and throughput of the CIoV as well as decrease the interference power to the PU.

关键词： cognitive Internet of vehicles reinforcement learning dynamic spectrum access Q-learning spectral efficiency

MULTI-CHANNEL TRANSMISSION STRATEGY FOR dynamic spectrum access

在线全文

学校读者我要写书评

暂无评论

Journal of Electronics(China) 2010年第3期27卷 345-352页

作者： Wu Yingxiao Yang Zhen Huaxin Consulting Co. Ltd Hangzhou 310014 China Institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China

Cognitive radio is a promising technology that deals with the scarcity of radio spectrum. In this paper, we propose a new multi-channel transmission strategy for dynamic spectrum access in cognitive radio network. Starting with the model of spectrum activities, we present the multi-channel transmission strategy which has primary user's protection mechanism to improve the spectrum efficiency and study its performance under perfect and imperfect sensing. Numerical example results reveal that the performance of the proposed strategy has the superiority with respect to capacity performance of cognitive users and the protection of primary users.

关键词： Transmission strategy dynamic spectrum access Multiple channels

The Research on Policy-management-based dynamic spectrum access Technology for Cognitive Network

在线全文

学校读者我要写书评

暂无评论

The Research on Policy-management-based Dynamic Spectrum Acc...

Self-Coexistence Among Cognitive Radio Networks Using Risk-Motivated Channel Selection Based Deference Structure

2009 ISECS International Colloquium on Computing, Communication, Control, and Management

作者： Lu Chuntao,Zhang Huyin,Wu Di School of Computer Wuhan University Wuhan,China An Hui Institute for Information Industry China Center for Information Industry Development Beijing,China

Nowadays,it is a very popular topic to improve the performance of cognitive *** aim to provide a solution for cognitive network,through the policy-based performance management system which we are *** this paper,we proposes the policy-based dynamic spectrum access management system framework at first,and the distributed policy repository to provide *** also, there would be a part to present our design about some new strategies for the policy repository,that with the technology features of cognitive network for dynamic spectrum access,a cognitive network can detect the use of local channel and real-time status to respond automatically to avoid interrupts.

关键词： Policy Cognitive network dynamic spectrum access

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2013年第3期18卷 242-249页

作者： Kenneth Ezirim Shamik Sengupta Department of Computer Science Graduate Center Department of Math. and Comp. Sci. John Jay College

Among cognitive radio networks there is a persistent trend of competition to acquire under-utilized and idle channels for data transmission. The competition for spectrum resources often results in the misuse of the spectrum resources as networks experience contention in attempt to access unoccupied spectrum bands. The competitive scenario causes cognitive radio networks to incur a huge amount of loss, which constitutes a major problem of self-coexistence among networks. As a way to minimize these losses we present a self-coexistence mechanism that allows cognitive radio networks to coexist with each other by implementing a risk-motivated channel selection based on deference structure. Cognitive radio networks form deference structure community to have more efficient access to a channel of interest and can defer transmission to one another on that channel, thereby minimizing the chances of conflicts. As part of the decision making process to become a member of a deference structure community, cognitive radio networks rely on a risk-motivated channel selection scheme to evaluate the tentative deference structure channel. We provide numerical and simulation results that demonstrates the benefits of the proposed self-coexistence mechanism and show how it helps networks to coordinate their spectrum activities, minimize contention experienced and improve their utility. We also emphasize on the importance of the deference structure community size with regards to the average performance of member networks.

关键词： dynamic spectrum access cognitive radio self-coexistence deference deference structure

Intelligent cognitive spectrum collaboration:Convergence of spectrum sensing,spectrum access,and coding technology

在线全文

学校读者我要写书评

暂无评论

Intelligent and Converged Networks 2020年第1期1卷 79-98页

作者： Peixiang Cai Yu Zhang Beijing National Research Center for Information Science and Technology (BNRist)Beijing 100084China Key Laboratory of Digital TV System of Guangdong Province and Shenzhen City Research Institute of Tsinghua University in ShenzhenShenzhen 518057China Department of Electronic Engineering Tsinghua UniversityBeijing 100084China

For a future scenario where everything is connected,cognitive technology can be used for spectrum sensing and access,and emerging coding technologies can be used to address the erasure of packets caused by dynamic spectrum access and realize cognitive spectrum collaboration among users in mass connection *** learning technologies are being increasingly used in the implementation of smart *** this paper,after an overview of several key technologies in the cognitive spectrum collaboration,a joint optimization algorithm of dynamic spectrum access and coding is proposed and implemented using reinforcement learning,and the effectiveness of the algorithm is verified by simulations,thus providing a feasible research direction for the realization of cognitive spectrum collaboration.

关键词： cognitive radio spectrum sensing dynamic spectrum access coding technology reinforcement learning joint optimization

Cooperative spectrum sharing of multiple primary users and multiple secondary users

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Digital Communications and Networks 2016年第4期2卷 191-195页

作者： Hang Liu Sha Hua Xuejun Zhuo Dechang Chen Xiuzhen Cheng Department of Electrical Engineering and Computer Science the Catholic University of America Washington DC USA Oualcomm Inc. San Diego CA USA Pattern Insight Inc. San Diego CA USA Uniformed Services University of the Health Sciences Bethesda MD USA Department of Computer Science the George Washington University Washington DC USA

This paper proposes a multiple-input multiple-output (MIMO) based cooperative dynamic spectrum access (DSA) framework that enables multiple primary users (PUs) and multiple secondary users (SUs) to cooperate in spectrum sharing. By exploiting MIMO in cooperative DSA, SUs can relay the primary traffic and send their own data at the same time, which greatly improves the performance of both PUs and SUs when compared to the non-MIMO time-division spectrum sharing schemes. Especially, we focus on the relay selection optimization problem among multiple PUs and multiple SUs. The network-wide cooperation and competition are formulated as a bargaining game, and an algorithm is developed to derive the optimal PU-SU relay assignment and resource allocation. Evaluation results show that both primary and secondary users achieve significant utility gains with the proposed framework, which gives all of them incentive for cooperation.

关键词： dynamic spectrum access MIMO Relay selection Cooperative spectrum sharing Bargaining game

An Intelligent Fuzzy Based Energy Detection Approach for Cooperative spectrum Sensing

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Circuits and Systems 2016年第6期7卷 1042-1050页

作者： Sitadevi Bharatula Meenakshi Murugappan Department of Electronics and Communication Engineering College of Engineering Guindy Anna University Chennai India

Cognitive radio systems are helpful to access the unused spectrum using the popular technique, referred to as spectrum sensing. spectrum sensing involves the detection of primary user (PU) signal using dynamic spectrum access. Cooperative spectrum sensing takes advantage of the spatial diversity in multiple cognitive radio user networks to improve the sensing accuracy. Though the cooperative spectrum sensing schemes significantly improve the sensing accuracy, it requires the noise variance and channel state information which may lead to transmission overhead. To overcome the drawbacks in conventional cooperative spectrum sensing, this paper proposes a fuzzy system based cooperative spectrum sensing. Selection combining (SC) and maximum ratio combining (MRC) are used at fuzzy based fusion center to obtain the value of the sensing energy. These energy values are utilized in finding the presence of PU, results in improved sensing accuracy. In addition, an intelligent fuzzy fusion algorithm determines the PU presence without the channel state information based on multiple threshold values. Simulation results show that the proposed scheme outperforms the existing schemes in terms of sensing accuracy.

关键词： Cognitive Radio (CR) spectrum Sensing Fuzzy System dynamic spectrum access Energy Detection Scheme

spectrum Occupancy Prediction for Realistic Traffic Scenarios: Time Series versus Learning-Based Models

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Communications and Information Networks 2018年第2期3卷 35-42页

作者： Anirudh Agarwal Aditya S.Sengar Ranjan Gangopadhyay The LNM Institute of Information Technology Rupa Ki NangalPost-Sumelvia-JamdoliJaipur 302031India

spectrum occupancy information is neces-sary in a cognitive radio network(CRN)as it helps in modeling and predicting the spectrum availability for efficient dynamic spectrum access(DSA).However,in a CRN,it is difficult to ascertain a priori the pattern of the spectrum usage of the primary user due to its stochastic *** this context,the spectrum occupancy predic-tion proves to be very useful in enhancing the quality of experience of the secondary *** paper investigates the practical prowess of various time-series modeling approaches and the machine learning(ML)techniques for predicting spectrum occupancy,based on a spectrum measurement campaign conducted in Jaipur,Rajasthan,***,the comparison analysis conducted between the above two approaches highlights the trade-off in terms of the respective performance depending upon the nature of the spectrum occupancy ***,prediction through ML-based recurrent neural network proves to perform reasonably well,thereby providing an accurate future spectrum occupancy information for DSA.

关键词： machine learning time-series models spectrum occupancy prediction dynamic spectrum access

Opportunistic Usage of Maritime VHF Band—Deployment Challenges for a New Regulatory Framework

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Wireless Engineering and Technology 2014年第1期5卷 1-10页

作者： Eduardo Bolas Nuno Borges de Carvalho José Neto Vieira Paulo Mónica de Oliveira Instituto de Telecomunicacoes/DETI Universidade de AveiroAveiroPortugal Naval Research Centre(CINAV)-Escola Naval AlmadaPortugal Instituto de Engenharia Electrónica e Telematica de Aveiro/DETI Universidade de AveiroAveiroPortugal

Similarly to other domains, maritime community requests for broadband services have been significantly increasing. Worldwide navigation footprint and the lack of practical alternatives to Satellite Communications (SATCOM) empower VHF band as the natural choice to support most of those demands. Nevertheless, the major challenge for an implementation of maritime broadband VHF services is unquestionably the spectrum availability and management. Eventually, the solution must include spectrum sharing, using a Cognitive Radio (CR) based approach, but unfortunately current regulatory framework and spectrum management regime are not appropriate for such concepts and emerging technologies. To overcome such constraints, it is necessary to address a whole field of regulatory and standardization issues in order to prepare an evolution towards a more flexible and dynamic approach to spectrum management and a transition that would ensure incumbents live operations and legacy systems. The required paradigm change encompasses a new policy definition, an enforcement mechanism implementation and a comprehensive transition plan. The presented analysis pretends to address the regulatory feasibility of a framework change, discusses its evolving process and points some challenges related with practical aspects associated to Quality of Service (QoS) enforcement metrics definition, centering the arguments in maritime VHF band.

关键词： Maritime Communications Broadband VHF Cognitive Radio Regulatory Framework dynamic spectrum access Metrics