A Review on Modern Spectrum Sensing and Assignment Techniques in CRN

Cognitive radio (CR) is ascending as an advanced technology with the aim of utilizing the unused spectrum bands in an opportunistic and dynamic way. Fixed spectrum allocation done by government based agencies leads to underutilization of resources. The segments of spectrum bands that are unused, are called “spectrum holes” or “white spaces”. The solution to this issue is provided by implementing CR technology. It allows users to determine the unused bands in spectrum, choose the suitable one (depending on availability and accessibility of the spectrum) and use them in the best way possible. Spectrum assignment plays a vital role in minimizing any possibility of interference between secondary and primary users. Because of the varying parameters of available spectrum along with the different QoS specifications of various networks, CR technology raise a range of challenges. Spectrum management functions should tackle these problems and ensure that the CR network runs smoothly. This article therefore presents a brief survey on CR networks, its architecture and other relevant functionalities like spectrum sensing, spectrum decision, spectrum sharing, and spectrum mobility.

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Sensing Techniques for Next Generation Cognitive Radio Networks

Advances in Wireless Technologies and Telecommunication - Sensing Techniques for Next Generation Cognitive Radio Networks ◽

10.4018/978-1-5225-5354-0.ch006 ◽

2019 ◽

pp. 108-124

Author(s):

Dhaya R. ◽

Rajeswari A. ◽

Kanthavel R.

Keyword(s):

Cognitive Radio ◽

Spectrum Sensing ◽

Cognitive Radio Networks ◽

Spectrum Sharing ◽

Spectrum Management ◽

Radio Networks ◽

Maximum Throughput ◽

Spectrum Mobility ◽

Static Allocation ◽

Spectrum Holes

Cognitive radio is the technology used to solve the problem of spectrum underutilization by performing spectrum sensing, spectrum management, spectrum sharing, and spectrum mobility. The primary goal of cognitive radio is open spectrum sharing. Spectrum is a scarce and valuable natural resource that has to be used very effectively. The static allocation of spectrum to the licensed users will lead to wastage of resources when the spectrum is unused by the licensed user. Spectrum sensing methodology helps in detecting the spectrum holes and enables the unlicensed users to access the unused bands in the licensed spectrum effectively without interfering the licensed users. Cognitive thinking takes wireless communication to the next level by sensing the electromagnetic environment and dynamically adjusts its operating parameters in order to achieve maximum throughput, mitigate interference, facilitate interoperability, etc. The chapter presents the basics of cognitive radio networks, its architecture, its application, and advantages of cognitive radio networks.

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The New Research of Spectrum Sensing Technology for Cognitive Radio

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.945-949.2301 ◽

2014 ◽

Vol 945-949 ◽

pp. 2301-2305

Author(s):

Yi Peng ◽

Yan Jun Wang

Keyword(s):

Cognitive Radio ◽

Wireless Communication ◽

Spectrum Sensing ◽

Communication Technology ◽

Spectrum Sharing ◽

Rapid Development ◽

Current Model ◽

Radio Spectrum ◽

Spectrum Management ◽

Sensing Technology

With the rapid development of wireless communication technology, the shortage of spectrum resources is becoming more and more serious, and may even become a bottleneck restricting of the development wireless communication technology in the future. Now, Spectrum sensing technology, spectrum sharing technology and spectrum management technology is the three core technologies of cognitive radio spectrum,and sensing technology is to implement the follow-up of spectrum sharing and the premise of spectrum management.So mainly to the current model of the cognitive radio spectrum sensing technology,to make a classification and comparison, finally it is concluded that cognitive users under the environment of higher signal-to-noise ratio, the better results of the perceived performance.

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The Cognitive Radio and Internet of Things

European Journal of Engineering Research and Science ◽

10.24018/ejers.2020.5.8.2012 ◽

2020 ◽

Vol 5 (8) ◽

pp. 899-903

Author(s):

Ammar Abdul-Hamed Khader ◽

Zozan Azeez Ayoub

Keyword(s):

Cognitive Radio ◽

Internet Of Things ◽

Spectrum Sensing ◽

Spectrum Sharing ◽

Spectrum Management ◽

Smart Technology

Cognitive Radio (CR) and Internet of Things (IoT) is an effective step into the smart technology world. Several frameworks are proposed to build CR and IoT. The phases of the interconnection between IoT and CR is; spectrum sensing, spectrum sharing, and spectrum management. This paper presents a survey of CR based IoT and mentions some previous works. It highlights with details the spectrum sensing stage for both narrowband and wideband.

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Basic Spectrum Sensing Techniques

Advances in Wireless Technologies and Telecommunication - Sensing Techniques for Next Generation Cognitive Radio Networks ◽

10.4018/978-1-5225-5354-0.ch004 ◽

2019 ◽

pp. 70-84

Author(s):

Bhuvaneswari P. T. V. ◽

Bino J.

Keyword(s):

Cognitive Radio ◽

Spectrum Sensing ◽

Spectrum Sharing ◽

Cognitive Radio Network ◽

Radio Spectrum ◽

Spectrum Management ◽

Radio Network ◽

Spectrum Band ◽

Radio Systems ◽

Networking Technology

Cognitive radio network (CRN) is an upcoming networking technology that can utilize both radio spectrum and wireless resources efficiently based on the information gathered from the past experience. There are two types of users in CRN, namely primary and secondary. PUs (PU) have the license to operate in certain spectrum band while the secondary (SU) or cognitive radio (CR) users do not have the license to operate in the desired band. However, they can opportunistically utilize the unused frequency bands. Spectrum sensing, spectrum management, spectrum sharing, and spectrum mobility are the four major functions of cognitive radio systems. The main objective of spectrum sensing is to provide better spectrum access to CR users, without causing any harmful interference to PUs. Sensing accuracy is considered as the most important factor to determine the performance of cognitive radio network. In this chapter, the challenges and requirement involved in spectrum sensing are detailed. Further, various spectrum sensing basic techniques are also discussed in detail.

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OPPORTUNISTIC APPROACH TO EXPLOIT WIRELESS SPECTRUM BY USE OF COGNITIVE RADIO

INTERNATIONAL JOURNAL OF COMPUTERS & TECHNOLOGY ◽

10.24297/ijct.v2i3b.2700 ◽

2012 ◽

Vol 2 (3) ◽

pp. 108-115

Author(s):

Tanu Preet Singh Preet ◽

Prof. R.K Singh ◽

Jaspreet Kaur ◽

Vishal Sharma

Keyword(s):

Cognitive Radio ◽

Spectrum Sensing ◽

Ad Hoc ◽

Spectrum Management ◽

Intrinsic Properties ◽

Research Topics ◽

Spectrum Mobility ◽

Wireless Spectrum ◽

Hoc Networks ◽

Spectrum Selection

Cognitive radio (CR) technology is envisaged to solve the problems in wireless networks resulting from the limited available spectrum and the inefficiency in the spectrum usage by exploiting the existing wireless spectrum opportunistically. In this paper, intrinsic properties and research on software defined cognitive radio (SDCR) are presented. Firstly brief introduction of Cognitive Radio is given along with its architecture.Â Then spectrum management of Cognitive Radio ad hoc networks (CRAHNs) and their main features like spectrum sensing, spectrum decision, spectrum selection and spectrum mobility are defined. At the end, Software Defined Cognitive Radio (SDCR), its hardware and software platform, along with research topics on SDCR are defined

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Transmission protocols in Cognitive Radio Mesh Networks

International Journal of Electrical and Computer Engineering (IJECE) ◽

10.11591/ijece.v5i6.pp1446-1451 ◽

2015 ◽

Vol 5 (6) ◽

pp. 1446

Author(s):

Anusha M ◽

Srikanth Vemuru ◽

T Gunasekhar

Keyword(s):

Cognitive Radio ◽

Spectrum Sensing ◽

Spectrum Sharing ◽

Cognitive Radio Network ◽

Mesh Networks ◽

Dynamic Spectrum ◽

Mac Protocols ◽

Radio Network ◽

Medium Access ◽

Primary Users

A Cognitive Radio (CR) is a radio that can adjust its transmission limit based on available spectrum in its operational surroundings. Cognitive Radio Network (CRN) is made up of both the licensed users and unlicensed users with CR enable and disabled radios. CR’S supports to access dynamic spectrum and supports secondary user to access underutilized spectrum efficiently, which was allocated to primary users. In CRN’S most of the research was done on spectrum allocation, spectrum sensing and spectrum sharing. In this literature, we present various Medium Access (MAC) protocols of CRN’S. This study would provide an excellent study of MAC strategies.

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An Energy Efficient Spectrum Aware Routing for Cognitive Radio Networks (CRNs)

International Journal of Sensors Wireless Communications and Control ◽

10.2174/2210327910999201102193851 ◽

2020 ◽

Vol 10 ◽

Author(s):

Dileep Reddy Bolla ◽

Jijesh J J ◽

Mahaveer Penna ◽

Shiva Shankar

Keyword(s):

Cognitive Radio ◽

Spectrum Sensing ◽

Cognitive Radio Networks ◽

Energy Efficient ◽

Research Work ◽

Spectrum Management ◽

Residual Energy ◽

Radio Networks ◽

Traffic Load ◽

The Impact

Back Ground/ Aims:: Now-a-days in the Wireless Communications some of the spectrum bands are underutilized or unutilized; the spectrum can be utilized properly by using the Cognitive Radio Techniques using the Spectrum Sensing mechanisms. Objectives:: The prime objective of the research work carried out is to achieve the energy efficiency and to use the spectrum effectively by using the spectrum management concept and achieve better throughput, end to end delay etc., Methods:: The detection of the spectrum hole plays a vital role in the routing of Cognitive Radio Networks (CRNs). While detecting the spectrum holes and the routing, sensing is impacted by the hidden node issues and exposed node issues. The impact of sensing is improved by incorporating the Cooperative Spectrum Sensing (CSS) techniques. Along with these issues the spectrum resources changes time to time in the routing. Results:: All the issues are addressed with An Energy Efficient Spectrum aware Routing (EESR) protocol which improves the timeslot and the routing schemes. The overall network life time is improved with the aid of residual energy concepts and the overall network performance is improved. Conclusion:: The proposed protocol (EESR) is an integrated system with spectrum management and the routing is successfully established to communication in the network and further traffic load is observed to be balanced in the protocol based on the residual energy in a node and further it improves the Network Lifetime of the Overall Network and the Individual CR user, along with this the performance of the proposed protocol outperforms the conventional state of art routing protocols.

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Novel filter bank-based cooperative spectrum sensing under practical challenges for beyond 5G cognitive radios

EURASIP Journal on Wireless Communications and Networking ◽

10.1186/s13638-020-01889-w ◽

2021 ◽

Vol 2021 (1) ◽

Author(s):

Sener Dikmese ◽

Kishor Lamichhane ◽

Markku Renfors

Keyword(s):

Spectrum Sensing ◽

Filter Bank ◽

Cooperative Spectrum Sensing ◽

Minimum Energy ◽

Cognitive Radios ◽

Spectrum Management ◽

Wireless Channel ◽

First Case ◽

Channel Effects

AbstractCognitive radio (CR) technology with dynamic spectrum management capabilities is widely advocated for utilizing effectively the unused spectrum resources. The main idea behind CR technology is to trigger secondary communications to utilize the unused spectral resources. However, CR technology heavily relies on spectrum sensing techniques which are applied to estimate the presence of primary user (PU) signals. This paper firstly focuses on novel analysis filter bank (AFB) and FFT-based cooperative spectrum sensing (CSS) techniques as conceptually and computationally simplified CSS methods based on subband energies to detect the spectral holes in the interesting part of the radio spectrum. To counteract the practical wireless channel effects, collaborative subband-based approaches of PU signal sensing are studied. CSS has the capability to relax the problems of both hidden nodes and fading multipath channels. FFT- and AFB-based receiver side sensing methods are applied for OFDM waveform and filter bank-based multicarrier (FBMC) waveform, respectively, the latter one as a candidate beyond-OFDM/beyond-5G scheme. Subband energies are then applied for enhanced energy detection (ED)-based CSS methods that are proposed in the context of wideband, multimode sensing. Our first case study focuses on sensing potential spectral gaps close to relatively strong primary users, considering also the effects of spectral regrowth due to power amplifier nonlinearities. The study shows that AFB-based CSS with FBMC waveform is able to improve the performance significantly. Our second case study considers a novel maximum–minimum energy detector (Max–Min ED)-based CSS. The proposed method is expected to effectively overcome the issue of noise uncertainty (NU) with remarkably lower implementation complexity compared to the existing methods. The developed algorithm with reduced complexity, enhanced detection performance, and improved reliability is presented as an attractive solution to counteract the practical wireless channel effects under low SNR. Closed-form analytic expressions are derived for the threshold and false alarm and detection probabilities considering frequency selective scenarios under NU. The validity of the novel expressions is justified through comparisons with respective results from computer simulations.

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Performance Analysis of Hybrid Radio Frequency and Free Space Optical Communication Networks with Cooperative Spectrum Sharing

Photonics ◽

10.3390/photonics8040108 ◽

2021 ◽

Vol 8 (4) ◽

pp. 108

Author(s):

Dong Qin ◽

Yuhao Wang ◽

Tianqing Zhou

Keyword(s):

Radio Frequency ◽

Communication Networks ◽

Free Space ◽

Spectrum Sharing ◽

Cumulative Distribution ◽

Free Space Optical ◽

Secondary Users ◽

Primary Users ◽

Cooperative Spectrum Sharing ◽

The Impact

This paper investigates the impact of cooperative spectrum sharing policy on the performance of hybrid radio frequency and free space optical wireless communication networks, where primary users and secondary users develop a band of the same spectrum resource. The radio frequency links obey Nakagami-m distribution with arbitrary fading parameter m, while the free space optical link follows gamma-gamma distributed atmospheric turbulence with nonzero pointing error. Because the secondary users access the spectrum band without payment, their behavior needs to be restricted. Specifically, the power of the secondary users is dominated by the tolerable threshold of the primary users. Considering both heterodyne and intensity modulation/direct detection strategies in optical receiver, the performance of optical relaying networks is completely different from that of traditional networks. With the help of bivariable Fox’s H function, new expressions for cumulative distribution function of equivalent signal to noise ratio at destination, probability density function, outage probability, ergodic capacity and symbol error probability are built in closed forms.

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