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A Literature Review on Spectrum Sensing in Cognitive Radio Applications

Cognitive radio is a promising technology to meet the requirements of efficient usage of limited available frequency spectrum for next generation technology and demand for high data transmission. Cognitive radio technology requires detection of primary user signals for dynamic allocation of spectrum hole to secondary users. Spectrum sensing is an important function and an active research area in this regard. In this paper, a literature review of spectrum sensing is discussed, presenting different research domains of spectrum sensing for cognitive radio networks. System models with different modelling techniques are explained that can implement spectrum sensing. It also includes a brief summary of research challenges associated with spectrum sensing. The main subject of this paper is classification of spectrum sensing technique based on number of users, their comparison and future scope of research. Finally, we present current wireless standards that employ spectrum sensing and hardware platforms that can implement spectrum sensing algorithms in real time environment.