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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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Journal ArticleDOI
TL;DR: Performance evaluations illustrate and validate that the performance of CR- CSMA/CA varies with the offered traffic load of secondary network and the spectrum utilization rate of primary network, respectively, and also show that CR-CSMA/ CA outperforms other relevant MAC protocols.
Abstract: In this paper, we consider the medium access control (MAC) protocol design for random access cognitive radio network (CRN). Based on asynchronous spectrum sensing technique and RTS/CTS mechanism, a new MAC protocol, namely, cognitive-radio-based carrier sense medium access with collision avoidance (CR-CSMA/CA) is proposed to coordinate the channel access of secondary network as well as protect the operation of primary network, which applies to both single and multiple channel models. Using the G/G/1 queuing model with consideration of unsaturated and saturated network condition, we develop a framework to analyze the proposed MAC protocol and also derive closed-form expressions of specific performance metrics such as normalized throughput, average packet service time, etc. Performance evaluations illustrate and validate that the performance of CR-CSMA/CA varies with the offered traffic load of secondary network and the spectrum utilization rate of primary network, respectively, and also show that CR-CSMA/CA outperforms other relevant MAC protocols.

57 citations

Journal ArticleDOI
TL;DR: This work presents a platform, called m@ANGEL, which adheres to autonomic computing principles, and aims at the provision of seamless cognitive connectivity to the mobile Internet, from a business level view of cognitive wireless access networks.
Abstract: B3G wireless access infrastructures can be realized through the concept of cognitive networks. In a B3G context, a network operator will rely on various alternate wireless access technologies, for realizing the appropriate business goals, such as capacity and QoS levels. Cognitive wireless access networks dynamically change their configuration, and in this respect the radio access technologies and spectrum used at the physical and MAC layers, in order to adapt to environment conditions. A cognitive infrastructure consists of reconfigurable elements and intelligent management functionality. This article focuses on the management part. We present a platform, called m@ANGEL, which adheres to autonomic computing principles, and aims at the provision of seamless cognitive connectivity to the mobile Internet. Our work starts from a business level view of cognitive wireless access networks. Technical requirements for m@ANGEL are identified, and the architecture of the platform is described. Moreover, the article describes the functionality and engineering challenges of the m@ANGEL components, which provide the means for monitoring, discovery, context acquisition, description of profiles/goals/agreements, resource and service brokerage, configuration negotiation, selection, and implementation. Finally, concluding remarks are drawn, and issues for the next phases of our work are identified

57 citations

Journal ArticleDOI
TL;DR: The authors propose a passive protected DCS self-healing network (PPDSHN) architecture using a passive protection cross-connect network for network protection that may apply to not only the centralized and distributed control DCS network architectures, but also asynchronous, SONET and ATM DCS networks.
Abstract: The self-healing mesh network architecture using digital cross-connect systems (DCSs) is a crucial part of an integrated network restoration system. The conventional DCS self-healing networks using logical channel protection may require a large amount of spare capacity for network components (such as DCSs) and may not restore services fast enough (e.g., within 2 s). The authors propose a passive protected DCS self-healing network (PPDSHN) architecture using a passive protection cross-connect network for network protection. For the PPDSHN architecture, network restoration is performed in the optical domain and is controlled by electronic working DCS systems. Some case studies have suggested that the proposed PPDSHN architecture may restore services within a two-second objective with less equipment cost than the conventional DCS self-healing network architecture in high-demand metropolitan areas for local exchange carrier networks. The proposed PPDSHN architecture may apply to not only the centralized and distributed control DCS network architectures, but also asynchronous, SONET and ATM DCS networks. Transparency of line rates and transmission formats makes the PPDSHN network even more attractive when network evolution is a key concern of network planning. >

57 citations

Proceedings ArticleDOI
08 Dec 2008
TL;DR: It is shown that the proposed technique not only reduces the mean detection time and bandwidth but also outperforms its non-sequential counterpart.
Abstract: Fast and accurate spectrum sensing is crucial in realizing a reliable cognitive network. Cooperative spectrum sensing can help reducing the mean detection time and increasing the agility of the sensing process. However, when the number of cognitive users is large, the bandwidth need for the control channel that are used to report the secondary user nodespsila results to the fusion center may become excessively large. In this paper, we apply the sequential probability ratio test (SPRT) to control the average number of the reporting bits. It is shown that the proposed technique not only reduces the mean detection time and bandwidth but also outperforms its non-sequential counterpart. We derive the relationships amongst the global performance, miss probability and false alarm probability and show how to control the average number of reports by thresholding the distributed cognitive users.

57 citations

Proceedings ArticleDOI
13 Apr 2008
TL;DR: It is shown that virtual wireless networks can be created, utilizing only the residual wasted bandwidth of the primary service providers, and are able to support large volumes of users, while still ensuring that QoS reliability requirements, such as blocking and dropping guarantees, are achieved.
Abstract: Cognitive radio presents a new approach to wireless spectrum utilization and management. In this work, the potential performance improvement gained by applying cognitive radio to multiple-provider wireless systems is investigated. It is shown that virtual wireless networks can be created, utilizing only the residual wasted bandwidth of the primary service providers. These virtual networks are able to support large volumes of users, while still ensuring that QoS reliability requirements, such as blocking and dropping guarantees, are achieved. A Markov chain-based analysis of classic and cognitive systems is complemented by simulations in order to present a quantified perspective of the potential benefits of cognitive radio techniques.

57 citations


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