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Communication Infrastructure for Smart Microgrids
Published in Sasi K. Kottayil, Smart Microgrids, 2020
Cognitive radio was initially brought as an extension to the software defined radio concept that led to development of full cognitive radio; but, later most of the research in this area focused on spectrum sensing cognitive radio. The biggest challenge in spectrum sensing cognitive radio is the design and development of high-quality spectrum sensing devices and algorithms. The main functions of cognitive radios are power control, spectrum sensing, and spectrum management. Power control is normally used in spectrum sharing cognitive radios to maximize the capacity of users considering interference power constraints. Spectrum sensing is the process of detecting unused spectrum and sharing it without adversely affecting the users. Spectrum management involves spectrum analysis and decision making to decide on the best spectrum band for meeting the user communication requirements, while not creating undue interference to other users.
Hybrid Overlay/Underlay Transmission
Published in T. Kishore Kumar, Ravi Kumar Jatoth, V. V. Mani, Electronics and Communications Engineering, 2019
C. S. Preetham, M. Sivaganga Prasad, T. V. Ramakrishna
With the widespread wireless communication technologies and demand for excessive spectrum, the need for intelligent wireless system that changes their mode of operation by being aware of its surrounding environment, for better spectrum utilization, is inevitable. The need for such a system is because of the inefficiency of the traditional spectrum management to utilize the spectrum efficiently. In the traditional spectrum management, the spectrum is allocated for various wireless standards or licensed users for their exclusive use. One of the technologies that have caught the attention of many researchers is cooperative spectrum-sharing systems. Cognitive radio (CR) and cooperative diversity (CD) are the two techniques that are used in this technology. Efficient spectrum utilization is provided by CR and CD improves the reliability of communication. Usually in such cooperative communication systems, there are several nodes in between the source and destination to be chosen as the relay node. The performance of such system can be improved by selecting one of the nodes as the best relay, based on a relay selection criterion. The classification of the relay selection schemes can be done into two types, partial relay selection and opportunistic relay selection. In the partial relay selection, a relay is chosen as the best relay based on the signal-to-noise ratio (SNR) at the first hop or at the second hop. The relay that has highest SNR at any one of the hop is chosen as the best relay. In the opportunistic relay selection, the relay is selected based on the end-to-end SNR value. The relay with highest end-to-end SNR value is chosen as the best relay.
Weak, Good, and Best Industry Practices
Published in Saad Z. Asif, 5G Mobile Communications Concepts and Technologies, 2018
Spectrum management is the overall process of regulating and administering access to and use of the electromagnetic spectrum (or radio frequency in the case of mobile communications). A primary goal of spectrum management is to ensure optimal use of the radio spectrum in social, economic, and technical terms [2]. Overall, its purpose is to mitigate radio spectrum pollution, rationalize and optimize the use of the spectrum, avoid and solve interference, allocate and assign in accordance with ITU-R regulations, assist the introduction of new wireless technologies, and coordinate wireless communications with neighbors and other administrations [3].
Cooperative communication based access technique for sensor networks
Published in International Journal of Electronics, 2020
Hu, Min, Xie, Wang, and Yuan (2008) aimed at reliable communications in industrial wireless technology; firstly introduced the current major wireless protocol, and challenging industrial environment; secondly addressed a distributed cooperative wireless sensor networks together with a dynamic spectrum management scheme based on a hybrid spread spectrum scheme. Feng and Wassell (2016) analysed the optimal power consumption of cluster-based multi-hop transmission for a cooperative wireless sensor network. Singh, Verma, and Pathak (2015) studied the power consumption and resource utilisation of a trust and reputation model deployed in a wireless sensor network. They also examined the impact of sensor augmentation parameter for static and dynamic wireless sensor network with trust and reputation models. Verma, Singh, and Pathak (2016) dealt with the impact of malicious servers over different trust and reputation models in wireless sensor networks.
Compact Corner Truncated Fractal Slot Antenna for Cognitive Radio Sensor Network
Published in IETE Journal of Research, 2023
The opportunistic utilization and spectrum management is an essential demand of today’s wireless communication system. Dynamic spectrum allocation (DSA) is the key technology to deal with the spectrum scarcity in the cognitive radio network (CRN). The cognitive radio (CR) exhibits high versatility in spectrum management to improve channel utility. The multiple efforts are studied and reported for sharing of the non-utilized spectrum of licensed primary user (PU) [1]. DSA is the prime approach to explore the opportunity between the licensed primary user PU and unlicensed secondary user (SU) for efficient spectrum utilization. Figure 1 shows the conceptual model of spectrum sharing between the primary and secondary user over channel vacancy.
Performance Analysis of a Dynamic Spectrum Assignment Technique for 6G
Published in IETE Journal of Research, 2022
In recent years, to deal with the demands of the services that rely on radio spectrum, much advancement in the policies related to spectrum management has been observed [1]. Hence, the current and future wireless systems require efficient spectrum allocation and management algorithms to assign and manage the enormous available spectrum [2]. The issues pertaining to spectrum auctions, spectrum trading, spectrum rights, etc., have been redefined with a view of achieving high spectrum utilization [3,4].