Search for dissertations about: "Spectrum"

Showing result 1 - 5 of 1867 swedish dissertations containing the word Spectrum.

  1. 1. On Finding Spectrum Opportunities in Cognitive Radios : Spectrum Sensing and Geo-locations Database

    Author : Mohamed Hamid; Ben Slimane; Niclas Björsell; Muhammad Imadua Rahman; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; COgnitive Radio; Dynamic Spectrum Access; Spectrum Opportunity; Spectrum Sensing; GEo-locations database;

    Abstract : 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. READ MORE

  2. 2. Implementing spectrum commons: Implications for Thailand

    Author : Nattawut Ard-Paru; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; spectrum commons; institutional analysis and development IAD framework; spectrum assignment; spectrum allocation; Radio Regulations RR ; World Radiocommunication Conference WRC ; spectrum management;

    Abstract : Spectrum is a natural and limited resource that needs to be managed both internationally and nationally because of the unique propagation characteristics of radio waves. Once transmitted, a radio signal propagates until its power is depleted. Furthermore, electromagnetic energy does not recognize borders between countries. READ MORE

  3. 3. Spectrum Assignment Policy: Towards an Evaluation of Spectrum Commons in Thailand

    Author : Nattawut Ard-Paru; Chalmers tekniska högskola; []
    Keywords : SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; collective use of spectrum; spectrum management; benefit and cost analysis; spectrum assignment; spectrum commons;

    Abstract : There is consensus among economists, engineers, and lawyers that a traditional command-and-control approach to spectrum assignment is inefficient and that a market-based or commons approach can be more efficient. The purpose of this thesis is to find the benefits of using spectrum commons for frequency assignment in Thailand. READ MORE

  4. 4. Topics in Dynamic Spectrum Access : Market Based Spectrum Sharing and Secondary User Access in Radar Bands

    Author : Miurel Tercero Vargas; Jens Zander; Mikael Prytz; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; spectrum sharing; radar band; cognitive radio; Telecommunication; Telekommunikation; Systems engineering; Systemteknik;

    Abstract : 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. READ MORE

  5. 5. Heterogeneous Materials - Diffusion, Laplace spectrum and NMR

    Author : Matias Nordin; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; perturbation; nmr; diffusion; laplace operator; spectrum; heterogeneous materials;

    Abstract : Relations to the effective diffusion constant and the relaxation rate of the time-dependent diffusion coefficient for porous systems are derived from the Laplace operator spectrum. The Padé approximation is then explained in terms of the Laplace operator spectrum. READ MORE