الفهرس 
Chapter 1: Introduction to cognitive radioOnly 14 pages are availabe for public view
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Abstract
The limited available spectrum and the inefficiency of the spectrum usage results in a new technology named Cognitive Radio (CR). Spectrum Sensing is a key function of cognitive radio to detect the spectrum holes.
In this thesis; classifications, types, challenges and applications of spectrum sensing are discussed. A modified system of wideband spectrum sensing based on non-uniform Multi-Coset sampling is proposed. The proposed system is designed to work on a totally blind input wideband signal with less power consumption and complexity. The proposed system is able to adapt its operating parameters, time offsets and number of active branches continuously based on the change of the active channels. from another perspective, Cooperative Wideband Sensing based on Adaptive Multi-Coset Sampling (CWS_AMCS) technique is proposed to overcome fading and shadowing problems. Simulation results reflected an accurate reconstructed signal, high probability of detection and low Mean Square Errors (MSE) even at low SNR.