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"ABSTRACTCognitive radio CR, an effective method for shortage of spectrum resources and sensing, can be exploited well in manufacturing for communicating with limited spectrums and monitoring equipment and environment. Although cooperative spectrum sensing in CR using coalition formation CF games can bring in better sensing quality, it is more complex. In this paper, we study two representative CF algorithms with different orders of CF and then present an enhanced CF algorithm based on the new order of maximum utility for two coalitions, aiming at complexity optimization and remaining sensing quality at the same time. It is certified by analyses and simulations that compared with two CF representative algorithms the improved CF one is simple in complexity and high in sensing quality simultaneously. The improved CF algorithm is also demonstrated to be available for the CRN constantly changing."

"Cognitive radio networks (CRN) will be widely deployed in the near future, and this SpringerBrief covers some important aspects of it, as well as highlighting optimization strategies in Resource Allocation and Spectrum Sensing in CRNs. The cognitive approach in radio access is introduced in the first part of this SpringerBrief, and then next the benefits of cooperative spectrum sensing are highlighted and a framework for studying it under realistic channel conditions is described. New exact closed-form expressions for average false alarm probability and average detection probability are derived in this scenario. A novel approximation to alleviate the computational complexity of the proposed models are also discussed.Once the spectrum opportunities are identified, efficient and systematic resource allocation (RA) shall be performed. The second part of this SpringerBrief describes the taxonomy for the RA process in CRN. A comprehensive overview of the optimization strategies of the CRN RA is also provided. The device-to-device (D2D) communication scenario is discussed, then as a case study and various optimization strategies for the application of the CR technology in the D2D realm is studied. The application of advanced geometric water-filling (GWF) approach in CRN D2D environment for optimum resource allocation is presented in detail. Numerical results provide more insight quantitatively. Overall, this book is suitable for a wide audience that include students, faculty and researchers in wireless communication area and professionals in the wireless service industry."

"This book highlights the need for an efficient Handover Decision (HD) mechanism to perform switches from one network to another and to provide unified and continuous mobile services that include seamless connectivity and ubiquitous service access. The author shows how the HD involves efficiently combining handover initiation and network selection process. The author describes how the network selection decision is a challenging task that is a central component to making HD for any mobile user in a heterogeneous environment that involves a number of static and dynamic parameters. The author also discusses prevailing technical challenges like Dynamic Spectrum Allocation (DSA) methods, spectrum sensing, cooperative communications, cognitive network architecture protocol design, cognitive network security challenges and dynamic adaptation algorithms for cognitive system and the evolving behavior of systems in general. The book allows the reader to optimize the sensing time for maximizing the spectrum utilization, improve the lifetime of the cognitive radio network (CRN) using active scan spectrum sensing techniques, analyze energy efficiency of CRN, find a secondary user spectrum allocation, perform dynamic handovers, and use efficient data communication in the cognitive networks.Identifies energy efficient spectrum sensing techniques for Cooperative Cognitive Radio Networks (CRN);Shows how to maximize the energy capacity by minimizing the outage probability;Features end-of-chapter summaries, performance measures, and case studies."

"Current spectrum management model, command and control, is creating a fundamental cause to drop the spectral efficiency of the radio spectrum in time and space by granting a right to Radio Access Technology (RAT) to access exclusively. In order to solve the spectrum scarcity, a number of bodies, headed by the FCC, have been taking actions to make new paradigm of spectrum management. Recently, the FCC announced a very interesting report (1). It pointed out that more than 7000 of radio spectrums are underutilized in certain times or geographic locations. This means that spectrum scarcity is not due to fundamental lack of spectrum instead because of wasteful static spectrum allocations. Hence, various spectrum sharing schemes which can raise spectrum utilization are investigated by research institutes. In this context, IEEE 802.22 WG which was organized in November 2004 has a purpose to provide wireless internet service to WRAN (Wireless Regional Area Network) user (or secondary user) using idle or unused TV spectrums not to disturb VHF/UHF TV band users (primary user). Since there are two types of users in terms of spectrum access priority, this coexistence is regarded as vertical sharing (2) that the secondary user utilizes licensed spectrums by opportunistic manner. The outstanding advantage of this sharing is to be realizable by little modifications of current spectrum regulation. Therefore, IEEE 802.22 activities have received a plenty of attentions."

"This book provides an overview of the latest research and development of new technologies for cognitive radio, mobile communications, and wireless networks. The contributors discuss the research and requirement analysis and initial standardization work towards 5G cellular systems and the capacity problems it presents. They show how cognitive radio, with the capability to flexibly adapt its parameters, has been proposed as the enabling technology for unlicensed secondary users to dynamically access the licensed spectrum owned by legacy primary users on a negotiated or an opportunistic basis. They go on to show how cognitive radio is now perceived in a much broader paradigm that will contribute to solve the resource allocation problem that 5G requirements raise. The chapters represent hand-selected expanded papers from EAI sponsored and hosted conferences such as the 12th EAI International Conference on Mobile and Ubiquitous Systems, the 11th EAI International Conference on Heterogeneous Networking for Quality, Reliability, Security and Robustness, the 10th International Conference on Cognitive Radio Oriented Wireless Networks, the 8th International Conference on Mobile Multimedia Communications, and the EAI International Conference on Software Defined Wireless Networks and Cognitive Technologies for IoT."

"This book provides a broad introduction to Cognitive radio, which attempts to mimic human cognition and reasoning applied to software defined radio and reconfigurable radio over wireless networks. It provides readers with significant technical and practical insights into different aspects of Cognitive radio, starting from a basic background, the principle behind the technology, the inter-related technologies and application to cellular and vehicular networks, the technical challenges, implementation and future trends. The discussion balances theoretical concepts and practical implementation. Wherever feasible, the different concepts explained are linked to application of the corresponding scheme in a particular wireless standard."

"This major reference work provides the most up-to-date research advances and theories in cognitive radio technology, from cognitive radio principles and theory to cognitive radio standards and systems, from fundamental limits of cognitive radio channels to cognitive radio networks, from the current cognitive radio practices and examples to future 5G cognitive cellular networks. This handbook will include some emerging applications of cognitive radio in areas such as smart grid, internet-of-things, big data, small cell/heterogeneous networks, and in 5G. The potential readers include postgraduate students, academic staff, telecommunications engineering, spectrum policy makers, and industry entrepreneurs."

"This book provides the most up-to-date research advances and theories in cognitive radio technology, from cognitive radio principles and theory to cognitive radio standards and systems, from fundamental limits of cognitive radio channels to cognitive radio networks, from the current cognitive radio practices and examples to future 5G cognitive cellular networks. The book will include some emerging applications of cognitive radio in areas such as smart grid, internet-of-things, big data, small cell/heterogeneous networks, and in 5G. The potential readers include postgraduate students, academic staff, telecommunications engineering, spectrum policy makers, and industry entrepreneurs."

"Kebutuhan pada jaringan komunikasi dengan kecepatan dan kapasitas yang tinggi terus meningkat seiring dengan berkembangnya teknologi informasi dan komunikasi. Teknologi 5G yang diterapkan pada Radio over Fiber yang disertai Wavelength Division Multiplexing dapat memenuhi kebutuhan tersebut. Dilakukan penelitian untuk mengetahui faktor-faktor yang berpengaruh terhadap transmisi Radio over Fiber yang melingkupi data rate, panjang kabel fiber optik, dan frekuensi radio. Dengan mengetahui pengaruh dari faktor-faktor tersebut, dilakukan perancangan skema fronthaul berbasis fiber optik yang mendukung aplikasi 5G. Hasil penelitian menunjukkan peningkatan data rate menghasilkan peningkatan kemungkinan terjadinya inter-symbol interference (ISI) dan peningkatan frekuensi radio meningkatkan kapasitas sebelum akhirnya mengalami saturasi pada frekuensi 40 Ghz, sedangkan panjang kabel fiber optik tidak memberikan pengaruh yang signifikan. Perancangan skema fronthaul dilakukan dengan frekuensi radio 26 GHz yang disertai penggunaan WDM, optical amplifier, dan dispersion compensating fiber (DCF). Simulasi pada skema upstream dan downstream yang dilakukan menunjukkan bahwa rancangan telah memenuhi target spesifikasi yang ditetapkan ITU dengan Q factor lebih besar dari 6 dan BER lebih kecil dari 10-9 pada setiap kanal. Penelitian dapat dikembangkan dengan menggunakan frekuensi radio yang tinggi dengan data rate yang lebih besar dan jangkauan kabel fiber optik yang lebih jauh.

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The demand for high-speed and high-capacity communication networks continues to increase along with the advancement of information and communication technology. 5G technology applied to Radio over Fiber accompanied by Wavelength Division Multiplexing (WDM) can meet these needs. A study was conducted to identify the factors affecting Radio over Fiber transmission, which include data rate, fiber optic cable length, and radio frequency. By understanding the impact of these factors, a fiber optic-based fronthaul scheme supporting 5G applications was designed. The study results show that increasing the data rate leads to a higher likelihood of inter-symbol interference (ISI), and increasing the radio frequency enhances capacity until it saturates at 40 GHz, while the fiber optic cable length does not have a significant impact. The fronthaul scheme was designed using a 26 GHz radio frequency, accompanied by WDM, optical amplifiers, and dispersion compensating fiber (DCF). Simulations of the upstream and downstream schemes demonstrated that the design meets the ITU's target specifications with a Q factor greater than 6 and a BER less than 10^-9 for each channel. The research can be further developed by utilizing higher radio frequencies with higher data rates and longer fiber optic cable reach."