Random multiple packet access with channel sensing for an energy limited cognitive radio systemRandom multiple packet access with channel sensing for an energy limited cognitive radio systemΠολλαπλή τυχαία προσπέλαση με Ανίχνευση καναλιού για ένα ενεργειακά περιορισμένο και έξυπνο ραδιοσύστημα μετάδοσης πακέτων Διπλωματική Εργασία Diploma Work 2016-04-262016enCognitive radio has emerged as an efficient approach to implement reuse of the licensed spectrums. How to appropriately deploy and construct the secondary network plays an important role. Several cognitive medium access control (MAC) protocols have been proposed for the secondary users (non-licensed users) to access the underutilized spectrum. In this thesis we consider a secondary user with energy harvesting capability. We design access schemes for the secondary user which incorporate random spectrum sensing and random access. The sensing and access probabilities of the secondary user, are dynamically computed such that the secondary user throughput is achieved is high, under the constraints that the primary queue is stable and that the primary queuing delay is kept low, in order to guarantee a quality of service (QoS) for the primary user.http://creativecommons.org/licenses/by/4.0/Πολυτεχνείο Κρήτης::Σχολή Ηλεκτρονικών Μηχανικών και Μηχανικών ΥπολογιστώνMpouzoukas_Dimitris_dip_2016.pdfChania [Greece]Library of TUC2016-04-26application/pdf3.0 MBfree Bouzoukas Dimitris Μπουζουκας Δημητρης Paterakis Michalis Πατερακης Μιχαλης Liavas Athanasios Λιαβας Αθανασιος Bletsas Aggelos Μπλετσας Αγγελος Πολυτεχνείο Κρήτης Technical University of Crete Opportunistic spectrum access Cognitive radios Wireless networks