A Survey on Cognitive Radio Spectrum Sensing: Classifications and Performance Comparison

The problem of spectrum scarcity has surfaced in recent years due to the under-utilization of spectrum in temporal and spatial domains. To address this issue, various spectrum sensing techniques have been proposed in literature to make use of idle bands in the spectrum. Owing to the adaptability of cognitive radio with regards to changes in spectrum band availability, better spectrum utilization may be achieved. In this paper, we carry out a survey of various spectrum sensing techniques proposed in literature. We identify the advantages and shortcomings associated with each of sensing techniques pertaining to narrow band as well as wide band spectrum sensing. We highlight the open issues and challenges associated with spectrum sensing to facilitate more productive research and present their comparison in terms of various performance parameters.