Cognitive Radio technology helps in designing wireless system for efficient deployment of radio spectrum with its sensing technique, self-adaptation and spectrum sharing. Spectrum sharing is an effective method of alleviating the scarcity of radio spectrum problem by allowing unlicensed users(secondary users) to coexist with licensed users (primary users) under the condition of protecting the l...

While bringing the potential for solving the spectrum underutilization problem using methods such as dynamic and opportunistic spectrum access, Cognitive Radios (CRs) also bring a set of security issues and potential breaches that have to be addressed. These issues come out mainly from the two important capabilities implemented within CRs: their cognition ability and reconfigurability. This cha...

Cognitive Radios are promising solutions to the problem of overcrowed spectrum. Using channel selection techniques the access can be opportunistic by using frequency hopping, frequency tracking and frequency coding. Spectrum sharing cognitive radio networks allows cognitive radio users to share the spectrum bands of the licensed users. This paper explores various cognitive radio spectrum sharin...

Software defined radio (sdr) technology has evolved rapidly and is now reaching market maturity, providing solutions for cognitive radio applications. Still, a lot of issues have yet to be studied. In this paper, we highlight the constraints imposed by recent radio protocols and we present current architectures and solutions for programming sdr. We also list the challenges to overcome in order ...

In the scope of the Adaptive Ad-hoc Freeband (AAF) project, an emergency network built on top of Cognitive Radio is proposed to alleviate the spectrum shortage problem which is the major limitation for emergency networks. Cognitive Radio has been proposed as a promising technology to solve today’s spectrum scarcity problem by allowing a secondary user in the non-used parts of the spectrum that ...

Recently, Cognitive radio and Smart Grid are two areas which have received considerable research impetus. Cognitive radios are fully programmable wireless devices that can sense their environment, and dynamically adapt their transmission waveform, channel access method, spectrum use, and networking protocols. It is widely anticipated that cognitive radio technology will become a general-purpose...

Radio spectrum needed for applications such as mobile telephony, digital video broadcasting (DVB), wireless local area networks (WiFi), wireless sensor networks (ZigBee), and internet of things is enormous and continues to grow exponentially. Since spectrum is limited and the current usage can be inefficient, cognitive radio paradigm has emerged to exploit the licensed and/or underutilized spec...

Cognitive Radio plays a major part in communication technology by resolving the shortage of the spectrum through usage of dynamic spectrum access and artificial intelligence characteristics. The element of spectrum sharing in cognitive radio is a fundamental approach in utilising free channels. Cooperatively communicating cognitive radio devices use the common control channel of the cognitive r...

Cognitive Radio Wireless Sensor Networks are emerging technology which provides cognitive capabilities to Wireless Sensor Networks. WSN operates in unlicensed band. Same spectrum band is shared by other wireless devices like Wi-Fi and Bluetooth. Due to this, the unlicensed spectrum is overcrowded which degrades the performance of WSNs. To overcome this issue, Cognitive Radio is integrated with ...