A survey on spectrum sensing algorithms for cognitive radio

The availability of radio spectrum is limited. The demand for high data transmission requires the increase in the spectrum which over burdens the available frequency spectrum because of licensed spectrum management. But on the other hand the studies indicate that the licensed spectrum is underutilized. Therefore this underutilized spectrum needs to be relocated dynamically so that the spectrum can be used by unlicensed user when it is not used by primary users. This paper provides an overview of spectrum sensing for cognitive radio for opportunistic spectrum access and related research topics The Cognitive Radio (CR) technology requires the detection of primary user signals at the secondary users to dynamically allocate the spectrum hole to the unlicensed user. The important task for cognitive radio is to detect the existence of primary user to reduce interference to the primary user. Therefore spectrum sensing is a most important part of the cognitive radio. A number of promising concepts for spectrum sensing in cognitive radio were briefly presented and discussed in this paper in the area of blind semi-blind and non-blind spectrum techniques.