Arash Parsa , Amin Aminzadeh Gohari , and Anant Sahai , “ Exploiting Interference Diversity for Event - Based Spectrum Sensing , ”
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چکیده
Starting from the San Francisco Bay Area on this map of the U.S. shaded by population density, we see that TV towers have footprints that do not cover everything. The uncovered spaces are “holes” in spectrum usage that can be reclaimed by cognitive radios. As we take a virtual trip along Interstate 80, we see from the plot at the top that there are lots of channels not being used throughout the U.S. However, the central figure shows that there are somewhat fewer opportunities where most people live. This figure was created by Mubaraq Mishra and is borrowed from A. Sahai, S.M. Mishra, R. Tandra, and K. Woyach, “Cognitive Radios for Spectrum Sharing,” to appear in the DSP Applications column in the IEEE Signal Processing Magazine for January 2009.
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