Unit:
Κατεύθυνση / ειδίκευση Τηλεπικοινωνιακά Συστήματα και Δικτυακές Τεχνολογίες (ΤΗΛ)Library of the School of Science
Supervisors info:
Λάζαρος Μεράκος Επιβλέπων Καθηγητής
Original Title:
Χωρική επαναχρησιμοποίηση φάσματος με δευτερογενή κατανομή πόρων βασισμένη στη θεωρία χρωματισμού γράφων
Summary:
Nowadays, the licensed spectrum is both spatially and temporarily
underutilized. This happens at an era where the requirements for ubiquitous
wireless services constantly grow, and in parallel more demanding applications
need support. A promising solution to these problems can be provided by
Opportunistic Spectrum Access (OSA), which targets on identifying and
exploiting local, instantaneous unutilized spectrum portions. This dissertation
constitutes such an OSA approach, where a network topology informed base
station of a cell takes advantage of the spatial system’s characteristics to
increase spectrum utilization. Respecting the primary operation of the standard
users and the necessary interference-free conditions, an algorithm has been
implemented, which decides which available resources can be reused and, thus,
allocated on a secondary basis to opportunistic users. In order to achieve
this, the system’s topology is represented by a graph and List-Coloring
algorithms are applied, which perform allocations of available resources to
opportunistic users’ pairs. The way, in which the topology map is established,
is also implemented. Derived results like the number of new secondary
assignments, the reuse percentage of the available spectrum and the percentage
of satisfied requests for resources show that this approach has much to offer
towards the direction of full spectrum utilization.
Keywords:
opportunistic spectrum access (OSA), resource allocation, spatial spectrum reuse, graph/list coloring, interference
Number of index pages:
15-16,17,19,85-86
File:
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document.pdf
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File access is restricted only to the intranet of UoA.
