There has been an exponential increase in spectrum demands due to new emerging wireless services and applications, making it harder to find unallocated spectrum bands for future usage. This potential resource scarcity is rooted at inefficient utilization of spectrum under static spectrum allocation. Therefore, a new concept of dynamic spectrum access (DSA) has been proposed to opportunistically...

Spectrum sensing is identified as one of the enabling technologies for spectrum opportunities detection in cognitive radio systems. Although the latest developments in cognitive radio regulation favor the database approach, spectrum sensing can provide reliable opportunistic spectrum access in dynamic and unpredictable environments [1]. Under these circumstances, the efficiency and reliability ...

Spectrum sensing is a key function of cognitive radio to prevent the harmful interference with licensed users and identify the available spectrum for improving the spectrum’s utilization. Various methods for spectrum sensing control, such as deciding which sensors should perform sensing simultaneously and finding the appropriate trade-off between probability of misdetection and false alarm rate...

The IEEE is developing a standard for cognitive wireless regional area networks operating in unused television channels. One of the cognitive features of this standard is spectrum sensing, which is used to identify unused television channels. This paper describes the requirements for spectrum sensing and the spectrum sensing framework. A description is given of the method used for evaluating sp...

Cognitive Radio (CR) is a radio communications and networking technology that has recently attracted considerable interest from academia as well as industry worldwide. It follows the design philosophy of Dynamic Spectrum Access (DSA) as opposed to a fixed spectrum allocation policy. The enabling technology for CR is spectrum sensing, which is the inference of presence/absence of primary users (...

The speed and accuracy of spectrum sensing techniques are essential factors in the performance of cognitive radio networks. The limitations imposed by computational complexity and a shortened monitoring time impede the success of spectrum sensing operation performed by cognitive radio nodes. Compressive sensing techniques are viewed as novel approaches to solve scalability problems in some sign...

Spectrum sensing in cognitive radio networks allows secondary users to sense the unused spectrum without causing interference to primary users. Cognitive radio requires more accurate sensing results from unused portions of the spectrum. Accurate spectrum sensing techniques can reduce the probability of false alarms and misdetection. In this paper, a two-stage spectrum sensing scheme is proposed...

Traditional spectrum sensing techniques such as energy detection, for instance, can sense the spectrum only when the cognitive radio (CR) is not in operation. This constraint is relaxed recently by some blind source separation techniques in which the CR can operate during spectrum sensing. The proposed method in this paper uses the fact that the primary spectrum usage is correlated across time ...

Cognitive radio (CR) is a key solution for the problem of inefficient usage of spectral resources. Spectrum sensing in each CR aims at detecting whether a preassigned spectrum band is occupied by a primary user or not. Conventional techniques do not allow the CR to communicate with its own base station during the spectrum sensing process. So, only a part of the frame can be used for cognitive d...