الفهرس يوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
Cognitive radio (CR) is used to overcome the spectrum scarcity problem, which results from {uFB01}xed allocation of wireless bands for di{uFB00}erent applications. CR allows unlicensed secondary users (SU) to exploit idle spectrum, which is not occupied by any licensed Primary User (PU), thus increasing the overall spectrum utilization. This should take place in a manner that assures no in{uFB02}uence on the operation of the PU itself. Decision of idle channel exploitation is a result of a process known as spectrum Sensing (SS). Accordingly, SS is a key element in the CR systems implementation and plays a major role in its overall performance. Many techniques have been developed for spectrum sensing, which vary in complexity and performance. Energy detection (ED) is a very popular technique for spectrum sensing because it is simple and does not require information about the primary signal. However, due to its poor performance under fading conditions, cooperative Sensing (CS) was suggested to enhance the robustness of the SS decisions