Can We Find (and Use) "Spectrum Holes"?: Spectrum Sensing and Spatial Reuse Opportunies in "Cognitive" Radio Systems
A main concern in spectrum overlays ("Cognitive Radio") has been the reliability of sensing techniques to predict the performance in the primary communication link if the secondary user decides to use the spectrum. The fundamental difficulty is that sensors detect the transmissions (i.e., the transmitters), whereas the communication performance is determined by the interference environment around the (possibly silent) receivers. In previous work, specific scenarios with rather simple propagation models, mostly neglecting the correlation properties between signal paths, have been used. In this paper, more realistic propagation models are used to compare the performance of various sensing and resource management strategies.