Browsing by Author "Milkias, Hailu"

Now showing 1 - 1 of 1
  • No Thumbnail Available
    Item
    Comparative Analysis of Blind Spectrum Sensing Techniques over Fading Channel
    (Addis Ababa University, 2018-12) Milkias, Hailu; Murad, Ridwan (PhD)
    A spectrum is a scarce and precious natural resource and a matter of concern with the rapidly growing wireless communications. However, studies show that licensed spectrum is underutilized. Cognitive radio system allows unlicensed users also called secondary users to access licensed spectrum band also known as spectrum hole of primary user when they are not occupied. To do this the secondary users need to continuously monitor the licensed user’s activity to find the unused band. Spectrum sensing is the key task for cognitive radio which prevents the unwanted interferences with authorized users to recognize available radio spectrum and enhance the usage of spectrum. Spectrum sensing is also a tough task because of shadowing, fading, and time-varying nature of wireless channels. This thesis investigates the difference in performance of energy detection and eigenvalue based blind spectrum sensing techniques (without having prior knowledge) by implementing it over different environmental models and compares the Receiver Operating Characteristics (ROC) curves. Evaluation and analysis of performance is done by using Monte Carlo method with MATLAB software. The implementation gives detail comparison between blind spectrum sensing technique performances over fading channel and multiple network nodes. In particular, the result shows the minimum required energy level for optimal detection (with acceptable interference) over fading channel and also how effectively cooperative