collaborative spectrum sensing (css) is an effective approach to improve the detection performance in cognitive radio (cr) networks. inherent characteristics of the cr have imposed some additional security threats to the networks. one of the common threats is primary user emulation attack (puea). in puea, some malicious users try to imitate primary signal characteristics and defraud the cr user...

the prevalent communications networks suffer from lack of spectrum and spectrum inefficiency. this has motivated researchers to develop cognitive radio (cr) as a smart and dynamic radio access promised solution. a major challenge to this new technology is how to make fair assignment of available spectrum to unlicensed users, particularly for smart grids communication. this paper introduces an i...

Application of cognitive radios as the wireless terminals in ad hoc networks in emergency situations has distinct advantages. Better bandwidth, interoperability, avoidance of interference, and ant-jamming capabilities are a few such advanta This paper deals with ad hoc networks incorporated with cognitive radios, which acts as wireless terminals, that can be used in emergency situations and can...

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Cognitive radio has been introduced by Mitola in 1999 as an extension to software radio [1] (Stevens USA). Cognitive radio extends the software radio with radio-domain model-based reasoning about etiquettes (set of RF bands, air interfaces, protocols, and spatial and temporal patterns that moderate the use of the radio spectrum). Cognitive radio enhances the flexibility of personal services thr...

Ad hoc network is a collection of wireless mobile nodes that dynamically form a temporary network without the use of any existing network infrastructure or centralized administration. A cognitive radio is a radio that can change its transmitter parameters based on interaction with the environment in which it operates. The basic idea of cognitive radio networks is that the unlicensed devices (co...

Cognitive Radio provides enhanced wireless communication performance through context-aware sensing and adaptation. Cooperative relay enhances network connection quality and improved system throughput. Applying cooperative relay communication technique on Cognitive Radio networks enables Cognitive Radio to opportunistically exploit cooperation between network nodes. This integrated design that b...

In this research paper Interference Model for Scheduling Algorithm in Cognitive Radio Networks (CRNs) is designed. In the advancement of 4G it plays vital role. [1]. The first phone call over a cognitive radio network was made on Monday 11 January 2010 in Centre for Wireless Communications at University of Oulu using CWC's cognitive radio network CRAMNET (Cognitive Radio Assisted Mobile Ad Hoc ...

in this paper, we consider a cooperative cognitive radio network in which there is an ofdm primary link and multiple single carrier secondary links.the primary link is required to maintain its secrecy rate above a predefined threshold. if the secrecy rate requirement is not satisfied, the secondary system help primary link to maintain its secrecy rate requirement. in doing so, the secondary trans...