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Cognitive network

About: Cognitive network is a research topic. Over the lifetime, 4213 publications have been published within this topic receiving 107093 citations.


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Proceedings ArticleDOI
07 Mar 2017
TL;DR: The literature review, the security models and requirements for CRNs, layered and cross-layers attacks against CRNs are addressed, and a new category of security issues and challenges have been introduced in the cognitive radio systems.
Abstract: One of the important trends which is supposed to have more attention in the system of cognitive radio is wireless security models. Security requirements for CRNs are the same as the general wireless networks, taking into consideration that the frequency band changes dynamically adding a specific feature when we deal with security of CRNs. A new category of security issues and challenges have been introduced in the cognitive radio systems, and providing security models to realize good and reasonable protection must be one of the main researchers interest. This paper addresses the literature review, the security models and requirements for CRNs, layered and cross-layers attacks against CRNs.

22 citations

Journal ArticleDOI
TL;DR: The maximum throughput region of this multiuser cognitive network is characterized by establishing inner and outer bounds and it is shown that when collision constraints are tight, the outer and inner bounds match.
Abstract: The problem of cognitive access of multiple primary channels by multiple cognitive users is considered. The primary transmission on each channel is modeled by a continuous time Markov on-off process. Cognitive access of the primary channels is realized via channel sensing. Each cognitive user adopts a slotted transmission structure, senses one channel in each slot and makes the transmission decision based on the sensing outcome. The cognitive transmissions in each channel are subject to collision constraints that limit their interference to the primary users. The maximum throughput region of this multiuser cognitive network is characterized by establishing inner and outer bounds. Under tight collision constraints, the inner bound is obtained by a simple orthogonalized periodic sensing with memoryless access policy and its generalizations. The outer bound, on the other hand, is obtained by relating the sum throughput with the interference limits. It is shown that when collision constraints are tight, the outer and inner bounds match. This maximum throughput region result is further extended by a generalized periodic sensing scheme with a mechanism of timing sharing. Under general collision constraints, another outer bound is obtained via Whittle's relaxation and another inner bound obtained via Whittle's index sensing policy with memoryless access. Packet level simulations are used to validate the analytical performance prediction.

22 citations

Proceedings ArticleDOI
21 Sep 2009
TL;DR: A novel routing algorithm for future multi-hop Cognitive Radio Networks that provides better adaptability to the environment and maximizes throughput in a number of realistic scenarios and outperforms recently proposed routing protocols for Cognitive Radio networks.
Abstract: Advancement of Cognitive Radio technology can remedy the problems encountered from bandwidth and spectrum access limitations. In Cognitive Radio Ad Hoc Networks routing is one of the most important issues to be addressed and desires deep investigation. Previously proposed routing protocols assume the presence of a connected path from the source to the destination. In some scenarios, due to the characteristics of ad hoc networks and the features of the used cognitive radios, this assumption is likely to be invalid. In this study, a novel routing algorithm for future multi-hop Cognitive Radio Networks is proposed. The main motivation is to maximize data rates and minimize data delivery latency for a set of user communication sessions to deliver messages for the case where there is no connected path from the source to the destination or when network is partitioned at the time a message is originated. Experimental evaluations are performed in the ns2 simulator. It has been shown that the proposed approach provides better adaptability to the environment and maximizes throughput in a number of realistic scenarios and outperforms recently proposed routing protocols for Cognitive Radio networks.

22 citations

Journal ArticleDOI
TL;DR: This paper proposes a heuristic exhaustive search-based Algorithm-1 and a computationally efficient suboptimal low complexity Karuh–Kuhn–Tucker (KKT) condition-basedAlgorithm-2 to determine the OPS in CRSN architecture using variable rate m-QAM modulation and simulation results reveal that proposed Al algorithm-2 outperforms Algorithms-1 by a significant margin in terms of its implementation time.
Abstract: Cognitive radio sensor networks (CRSNs) is the state-of-the-art communication paradigm for power constrained short range data communication. It is one of the potential technologies adopted for Internet of Things (IoT) and other futuristic machine-to-machine-based applications. Many of these applications are power constrained and delay sensitive. Therefore, CRSN architecture must be coupled with different adaptive and robust communication schemes to take care of the delay and energy efficiency at the same time. Considering the tradeoff that exists in terms of energy efficiency and overhead delay for a given data packet length, it is proposed to transmit the physical layer payload with an optimal packet size (OPS) depending on the network condition. Furthermore, due to the cognitive feature of CRSN architecture overhead energy consumption due to channel sensing and channel handoff plays a critical role. Based on the above premises, in this paper, we propose a heuristic exhaustive search-based Algorithm-1 and a computationally efficient suboptimal low complexity Karuh–Kuhn–Tucker (KKT) condition-based Algorithm-2 to determine the OPS in CRSN architecture using variable rate m-QAM modulation. The proposed algorithms are implemented along with two main cognitive radio assisted channel access strategies based on distributed time slotted-cognitive medium access control (DTS-CMAC) and centralized common control channel-based cognitive medium access control (CC-CMAC) and their performances are compared. The simulation results reveal that proposed Algorithm-2 outperforms Algorithm-1 by a significant margin in terms of its implementation time. For the exhaustive search-based Algorithm-1 the average time consumed to determine OPS for a given number of cognitive users is 1.2 s, while for KKT-based Algorithm-2, it is of the order of 5–10 ms. CC-CMAC with OPS is most efficient in terms of overall energy consumption but incurs more delay as compared to DTS-CMAC with OPS scheme.

22 citations

Proceedings ArticleDOI
Jae Moung Kim1, Sung Hwan Sohn1, Ning Han1, Guanbo Zheng1, Young Min Kim1, Joo Kwan Lee1 
15 May 2008
TL;DR: A software testbed which is developed to implement the cognitive radio system is presented and the basic functions of cognitive radio are explored and implemented, including spectrum sensing and dynamic spectrum management.
Abstract: Cognitive Radio is considered as a potential solution to improve spectrum utilization via opportunistic spectrum sharing. In this paper, we present a software testbed which is developed to implement the cognitive radio system. The basic functions of cognitive radio are explored and implemented, including spectrum sensing and dynamic spectrum management. The testbed is able to verify the overall performance of cognitive radio technology. Furthermore, it provides an important system model to verify the effectiveness of the new algorithms in future study. The simulation on the testbed demonstrates that primary and secondary users can coexist. This is able to convince regulatory authorities as well as primary users to enable the implementation of cognitive radio technology.

21 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202317
202234
202175
2020104
2019121
2018134