Cognitive radio (CR) is designed to detect available frequency bands/channels. Spectrum sensing plays a critical role in CR with energy detection being the most common method. In our paper, we implement energy detection using GNU Radio and USRP boards as a test-bed. Specifically, energy detection is performed by using blocks in GNU Radio Companion (GRC) to calculate the energy of a present sign...

Spectrum sensing is a challenging task for cognitive radio. In this paper we analyze collaborative spectrum sensing over Nakagami fading channel in cognitive radio. Through computer simulation, we evaluate the performance of collaborative spectrum sensing and signal detection by employing OR, AND and MAJORITY rules as decision combining. Energy detection is one of the popular spectrums sensing ...

Rapid development of new and ever expanding wireless applications and services, spectrum resources are facing huge demands. Currently, spectrum allotment is done by giving each new service with its own fixed frequency block. As more and more technologies are moving towards fully wireless, demand for spectrum is enhancing. In this context, a new technology, cognitive radio (CR) has been come out...

Due to fixed available spectrum and the incomplete use of spectrum use necessitate a new communication technology, known as cognitive radio (CR). Cognitive radio is an intelligent device which can easily sense the available channel in an available spectrum. For spectrum sensing it basically uses three techniques Energy Detection, Matched Filter Detection and Cyclostationary Detection. In this p...

The idea of Cognitive Radio (CR) is to share the spectrum between a user called primary, and a user called secondary. Dynamic Spectrum Access (DSA) is a new spectrum sharing paradigm in cognitive radio that allows secondary users to access the abundant spectrum holes in the licensed spectrum bands. DSA is an auspicious technology to alleviate the spectrum scarcity problem and increase spectrum ...

Cognitive Radio Ad Hoc Networks (CRAHNs) constitute a viable solution to solve the current problems of inefficiency in the spectrum allocation, and to deploy highly reconfigurable and selforganizing wireless networks. Cognitive Radio (CR) devices are envisaged to utilize the spectrum in an opportunistic way by dynamically accessing different licensed portions of the spectrum. However the phenom...

this project aims to design and implement a new Cognitive Radio (CR) receiver targeting the IEEE 802.22 standard as the first world-wide CR standard. In fact, this project starts with a study and a comparison of various CR receivers. This study leads to the presentation of a new approach that was adopted based on sub-band sensing technique for a CR receiver. In addition, we demonstrate a system...

Radio communication, one of core contents in wireless communication, is facing a great crisis of running out of resource. Unlike other energy crisis which can be solved by using all kinds of alternative energy, the only resource of radio communication is channel, in another word, spectrum. Rather than sticking on trying to achieve the rest one percent of capacity, more and more scholars start t...

This paper mathematically proposes channel estimation algorithms for Cognitive Radio (CR) in terms of Mean Square Error (MSE) and analysis of its Bit Error Rate (BER) performance. As cognitive radio associates itself with the family of opportunistic communication for using frequency spectrum efficiently, issues such as spectrum sensing and channel estimation gain attention. When the main issue ...

Cognitive Radio (CR) is aimed at increasing the efficiency of spectrum utilization by allowing unlicensed users to access, in an opportunistic and non-interfering manner, some licensed bands temporarily and/or spatially unoccupied by the licensed users. The analysis of CR systems usually requires the spectral activity of the licensed system to be represented and characterized in a simple and tr...