Architecture of Cognitive Radio Networks

Today’s wireless networks are characterized by fixed spectrum assignment policy. The spectral scarcity and the inefficiency in the spectrum usage necessitate a new communication paradigm to exploit the existing wireless spectrum, opportunistically. Cognitive Radio (CR) is that very paradigm for wireless communication, in which either a network or a wireless node reconfigures its transmission or reception parameters to communicate efficiently avoiding interference with licensed or unlicensed users. CR adapts itself to the newer environment on the basis of its intelligent sensing and captures the best available spectrum to meet user communication requirements. When the radio link features are extended to the network layer, the cognitive radios form the cognitive radio network. This book chapter is focused on cognitive radio network, architecture of the CR, and its relevance in the wireless and mobile Ad Hoc networks.

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Modeling of Software Defined Radio Architecture and Cognitive Radio

Advances in Wireless Technologies and Telecommunication - Cognitive Radio Sensor Networks ◽

10.4018/978-1-4666-6212-4.ch006 ◽

2014 ◽

pp. 127-158 ◽

Cited By ~ 9

Author(s):

Jyoti Sekhar Banerjee ◽

Arpita Chakraborty

Keyword(s):

Cognitive Radio ◽

Software Defined Radio ◽

Network Architecture ◽

Ad Hoc ◽

Cognitive Radio Network ◽

Cognitive Radios ◽

Radio Link ◽

Radio Network ◽

Hoc Networks ◽

Wireless Node

Today's wireless networks are characterized by fixed spectrum assignment policy. The spectral scarcity and the inefficiency in the spectrum usage necessitate new communication paradigms to exploit the existing wireless spectrum, opportunistically. Software Defined Radio (SDR) and Cognitive Radio (CR) are the very paradigms for wireless communication, in which either a network or a wireless node reconfigures its transmission or reception parameters to communicate efficiently, avoiding interference with licensed or unlicensed users. CR adapts itself to the newer environment on the basis of its intelligent sensing and captures the best available spectrum to meet user communication requirements. When the radio link features are extended to the network layer, the cognitive radios form the cognitive radio network. This chapter is focused on software defined radio, its architecture, its limitations, evolution to cognitive radio network, architecture of the CR, and its relevance in wireless and mobile ad-hoc networks.

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Architecture design of ad-hoc cognitive radio network

Indian Journal of Science and Technology ◽

10.17485/ijst/2018/v11i18/123044 ◽

2018 ◽

Vol 11 (18) ◽

pp. 1-7

Author(s):

P. Surendar ◽

A. Sridevi ◽

R. Sona ◽

◽

...

Keyword(s):

Cognitive Radio ◽

Ad Hoc ◽

Cognitive Radio Network ◽

Architecture Design ◽

Radio Network

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Actor–Critic-Algorithm-Based Accurate Spectrum Sensing and Transmission Framework and Energy Conservation in Energy-Constrained Wireless Sensor Network-Based Cognitive Radios

Wireless Communications and Mobile Computing ◽

10.1155/2019/6051201 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

Hurmat Ali Shah ◽

Insoo Koo ◽

Kyung Sup Kwak

Keyword(s):

Cognitive Radio ◽

Ad Hoc Networks ◽

Spectrum Sensing ◽

Optimization Problem ◽

Ad Hoc ◽

Cognitive Radios ◽

Residual Energy ◽

Current Time ◽

Energy Constrained ◽

Hoc Networks

Spectrum sensing is of the utmost importance to the workings of a cognitive radio network (CRN). The spectrum has to be sensed to decide whether the cognitive radio (CR) user can transmit or not. Transmitting on unoccupied spectrum becomes a hard task if energy-constrained networks are considered. CRNs are ad hoc networks, and thus, they are energy-limited, but energy harvesting can ensure that enough energy is available for transmission, thus enabling the CRN to have a theoretically infinite lifetime. The residual energy, along with the sensing decision, determines the action in the current time slot. The transmission decision has to be grounded on the sensing outcome, and thus, a combined sensing–transmission framework for the CRN has to be considered. The sensing–transmission framework forms a Markov decision process (MDP), and solving the MDP problem exhaustively through conventional methods cannot be a plausible solution for ad hoc networks such as a CRN. In this paper, to solve the MDP problem, an actor–critic-algorithm-based solution for optimizing the action taken in a sensing–transmission framework is proposed. The proposed scheme solves an optimization problem on the basis of the actor–critic algorithm, and the action that brings the highest reward is selected. The optimal policy is determined by updating the optimization problem parameters. The reward is calculated by the critic component through interaction with the environment, and the value function for each state is updated, which then updates the policy function. Simulation results show that the proposed scheme closely follows the exhaustive search scheme and outperforms a myopic scheme in terms of average throughput achieved.

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Joint Channel Assignment and Power Allocation Based on Maximum Concurrent Multicommodity Flow in Cognitive Radio Networks

Wireless Communications and Mobile Computing ◽

10.1155/2018/3545946 ◽

2018 ◽

Vol 2018 ◽

pp. 1-14 ◽

Cited By ~ 4

Author(s):

Ahmed Salah ◽

Heba M. Abdel-Atty ◽

Rawya Y. Rizk

Keyword(s):

Cognitive Radio ◽

Cognitive Radio Network ◽

Multipath Routing ◽

Multicommodity Flow ◽

Radio Network ◽

Communication Paradigm ◽

Multicommodity Flow Problem ◽

Promising Solution ◽

Joint Channel ◽

Networking Technology

Emerging cognitive radio networking technology potentially provides a promising solution to the spectrum underutilization problem in wireless access. In this paper, a cross-layer routing for secondary multihop is studied in cognitive radio network operating in television white spaces. The framework considers a joint channel, power, and routing assignment under signal to interference noise ratio (SINR) constraints. The problem is formulated as a maximum concurrent multicommodity flow problem. The goal of conducting this research is to develop a new routing protocol for the secondary multihop cognitive radio network. Therefore, the objective of this paper focuses on maximizing a flow rate scaling factor. Moreover, the paper focuses on achieving multipath routing when it is possible under SINR constraints to utilize all possible unused channels efficiently. The numerical results proved the strength of the proposed algorithm in its routing ability under the physical model of SINR, in addition to the ability of using multipath routing if there are available free channels to be used in the cognitive communication paradigm.

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Wireless Transport Protocol Variants for Cognitive Radio Networks

APTIKOM Journal on Computer Science and Information Technologies ◽

10.11591/aptikom.j.csit.144 ◽

2018 ◽

Vol 3 (3) ◽

pp. 106-112

Author(s):

G Shine Let ◽

G Josemin Bala ◽

W. Magdalene

Keyword(s):

Cognitive Radio ◽

Frequency Band ◽

Cognitive Radio Networks ◽

Cognitive Radio Network ◽

Transmission Control Protocol ◽

Radio Networks ◽

Transport Protocol ◽

Radio Network ◽

Communication Paradigm ◽

Wireless Transport

Scarce wireless resources, lead to development of cognitive radio network as a solution to unlicensed users communication in the licensed frequency band. In response to the behavior of licensed users communication, unlicensed users communication need to change from one frequency band to another band. In this communication paradigm, the performance of unlicensed users transmission control protocol gets degraded due to the features of cognitive radio network. To overcome this, several authors suggested quite a few modifications in the existing wireless transport protocol for cognitive radio network environment. This paper gives an overview of different transport protocols used for unlicensed users’ communication in cognitive radio networks

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