Sökning: "spectrum access"
Visar resultat 1 - 5 av 132 avhandlingar innehållade orden spectrum access.
1. Topics in Dynamic Spectrum Access : Market Based Spectrum Sharing and Secondary User Access in Radar Bands
Sammanfattning : The steady growth in demand for spectrum has increased research interest in dynamic spectrum access schemes. This thesis studies some challenges in dynamic spectrum access based on two strategies: open sharing and hierarchical access. LÄS MER
2. On Finding Spectrum Opportunities in Cognitive Radios : Spectrum Sensing and Geo-locations Database
Sammanfattning : The spectacular growth in wireless services imposes scarcity in term of the available radio spectrum. A solution to overcome this scarcity is to adopt what so called cognitive radio based on dynamic spectrum access. LÄS MER
Sammanfattning : The exploding increase of wireless communications combined with the existing inefficient usage of the licensed spectrum gives a strong impetus to the development and standardization of cognitive radio networking and communications. In this dissertation, a framework for Dynamic Spectrum Access (DSA) is first presented, which is the enabling technology for increasing the spectral efficiency of wireless communications. LÄS MER
Sammanfattning : The UHF band between 470-790 MHz, currently occupied by digital ter- restrial TV (DTT) distribution in Europe, is widely regarded as a premium spectrum band for providing mobile coverage. With the exponential increase in wireless data traffic in recent years, there has been growing interests in gaining access to this spectrum band for wireless broadband services. LÄS MER
Sammanfattning : Abstract. The number of mobile devices is constantly growing, and the exclusivestatic spectrum allocation approach is leading to the spectrum scarcity problem whensome of the licensed bands are heavily occupied and others are nearly unused.Spectrum sharing and opportunistic spectrum access allow achieving more efficientspectrum utilization. LÄS MER