Cognitive Radio offers a solution by utilizing the spectrum holes that represent the potential opportunities for noninterfering use of spectrum which requires three main taskscognitive Spectrum Sensing, Spectrum Analysis and Spectrum Allocation modulation techniques. Spectrum involves obtaining the spectrum usage characteristics across multiple dimensions such as time, space, frequency, and cod...

Searching for spectrum holes in practical wireless channels where primary users experience multipath fading and shadowing, with noise uncertainty, limits the detection performance significantly. Moreover, the detection challenge will be tougher when different band types have to be sensed, with different signal and spectral characteristics, and probably overlapping spectra. Besides, primary user...

With the rapid requirement and development of the green ICT (Information and Communication Technology) technology, the demand for dynamically radio spectrum resources has significantly attentions. The low utilization of licensed spectrum leads to the scarcity of the spectrum resource. The emerging cognitive radio (CR) systems become increasingly important in the wireless green communication. In...

Cognitive radio has been proposed as a possible solution to improve spectrum utilization via opportunistic spectrum sharing that will be done by autonomous detection of vacant bands in the radio spectrum. Spectrum sensing is the very task upon which the entire operation of cognitive radio rests. In this paper a new spectrum sensing method for cognitive radio systems based on cyclic autocorrelat...

The growing demand for wireless applications and services on the one hand, and limited available radio spectrum on the other hand have made cognitive radio (CR) a promising solution for future mobile networks. It has attracted considerable attention by academia and industry since its introduction in 1999 and several relevant standards have been developed within the last decade. Cognitive radio ...

Nowadays, cognitive radio is one of the most promising paradigms in the arena of wireless communications, as it aims at the proficient use of radio resources. Proper utilization of the radio spectrum requires dynamic spectrum accessing. To this end, spectrum sensing is undoubtedly necessary. In this chapter, various approaches for dynamic spectrum access scheme are presented, together with a su...

– Over the last decade the world of wireless communications has been undergoing some crucial changes, which have brought it at the forefront of international research and development interest, eventually resulting in the advent of a multitude of innovative technologies and associated products such as WiFi, WiMax, 802.20, 802.22, wireless mesh networks and software defined radio. Such a disparat...

Cognitive radio is a breakthrough technology which is expected to have a profound impact on the way radio spectrum will be accessed, managed and shared in the future. In this paper I examine some of the implications of cognitive radio for future management of spectrum. Both a near-term view involving the opportunistic spectrum access model and a longer-term view involving a self-regulating dyna...

In this paper, we propose a new approach based on Cognitive Radio technology to address the challenges for ensuring connectivity in remote areas of Africa. Indeed, the current network coverage is concentrated around the cities with high density of population. Through the deployment of Cognitive Radio, emergency services in rural areas will benefit from low cost access networks. Cognitive Radio ...

Computing and communications are central issues in cognitive radio networks. The cognitive users are increasing exponentially and the available spectrum resource is constant. Therefore, efficient usage of spectrum through cognitive radio networks is essential. The real-time communications in cognitive radio networks with increasing demand for spectrum is possible through nanocomputing. Nanocomp...