Spectrum sensing remains a challenge in the context of cognitive radio networks (CRNs). Compared with traditional single-user sensing, cooperative spectrum sensing (CSS) exploits multiuser diversity to overcome channel fading, shadowing, and hidden terminal problems, which can effectively enhance the sensing performance and protect licensed users from harmful interference. However, for a large ...

As the use of Cognitive Radio is increasing day by day, the problems related to spectrum sensing is also increasing. This paper presents a survey on different spectrum sensing methodologies. Furthermore, various sensing features like multi-dimensional spectrum sensing, cooperative sensing, dynamic spectrum access, external sensing algorithms and other alternative sensing methods are reviewed.

As Cognitive Radio Networks (CRN) gain in popularity as an extremely promising wireless technology that can alleviate the apparent spectrum scarcity and support innovative wireless applications; they will become bigger targets for hackers. Moreover, they will also be exposed to diverse security threats especially at the PHY-layer spectrum sensing module. Hence, security consideration is central...

As the deployment of new wireless devices and applications is growing rapidly there is an increase in demand for wireless radio spectrum. Researchers show that more than 70% of available spectrum is not used efficiently. For efficient utilization of spectrum we need to know whether the spectrum is used by primary user or not which is called Spectrum Sensing. The concept Cognitive Radio is propo...

Remote sensing can be defined as the “acquisition and measurement of data/information on some property(ies) of a phenomenon, object, or material by a recording device not in physical, intimate contact with the feature(s) under surveillance” (Short 1997). Scientists employing remote sensing are able to collect vast quantities of data quickly and efficiently for rapid analysis. One potential use ...

This paper evaluates the impact of removing random noise of radiance data using a spectral-spatial smoothing approach on data compression onboard a hyperspectral satellite. A datacube acquired using a Short Wave Infrared Full Spectrum Imager II for target detection application of hyperspectral data was tested. The impact was evaluated using both the statistical based measures and a remote sensi...

In this paper, we consider a cognitive radio network that consists of one cognitive base station (CBS) and multiple cognitive users (CUs) in the presence of an eavesdropper. In the cognitive radio network, CBS first detects whether there is spectrum hole through spectrum sensing and then communicates with CUs over the detected spectrum hole. Due to the broadcast nature of wireless transmission,...