A Survey on Spectrum Sensing Challenges in Wireless Cognitive Sensor Networks

Natural frequency spectrum is scared resource; the efficient use of it can only accommodate the need of future computing world. Opportunistic unlicensed access to the unused frequency bands across the licensed radio spectrum is currently being investigated as a means to increase the efficiency of spectrum usage. The ability to reliably and autonomously identify unused frequency bands is envisaged as one of the main functionalities of cognitive radios. On the other hand, spectrum sensing is one of the most challenging issues in cognitive radio systems. In this paper, a survey of spectrum sensing methodologies for cognitive radio is presented. Various aspects of spectrum sensing problem and challenges associated with it are studied. Cooperative sensing concept and its various forms are also introduced. Wireless sensor network concept, its standard and its protocol stack are discussed. Finally, the research challenges in wireless cognitive sensor networks are given.

Keywords:

Spectrum sensing , cooperative spectrum sensing , cognitive radio , wireless cognitive sensor network