Date Added: Jun 2011
Public Safety Communications (PSC) are invaluable in safety critical scenarios such as floods or earthquakes when commercial communication systems fall down. Cognitive Radio (CR) approach that is independent of other communication systems provides flexibility and certainty. One of the key issues is to reliably find unused radio channels also in the situations when there is no a priori information about possible other users. In this paper, the authors propose using the Two-Dimensional Localization Algorithm based on Double-thresholding with Adjacent Cluster Combining (2-D LAD ACC) method for detecting free channels.