Sökning: "power spectrum"

Visar resultat 1 - 5 av 296 avhandlingar innehållade orden power spectrum.

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

    Författare :Mohamed Hamid; Ben Slimane; Niclas Björsell; Muhammad Imadua Rahman; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; COgnitive Radio; Dynamic Spectrum Access; Spectrum Opportunity; Spectrum Sensing; 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

  2. 2. Implementing spectrum commons: Implications for Thailand

    Författare :Nattawut Ard-Paru; Chalmers University of Technology; []
    Nyckelord :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;

    Sammanfattning : 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. LÄS MER

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

    Författare :Nattawut Ard-Paru; Chalmers University of Technology; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; collective use of spectrum; spectrum management; benefit and cost analysis; spectrum assignment; spectrum commons;

    Sammanfattning : 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. LÄS MER

  4. 4. Tomographic studies of the 21-cm signal during reionization : Going beyond the power spectrum

    Författare :Sambit K. Giri; Garrelt Mellema; Benoît Semelin; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; reionization; non-gaussianity; first stars; image processing; Astronomy; astronomi;

    Sammanfattning : The formation of the first luminous sources in the Universe, such as the first generation of stars and accreting black holes, led to the ionization of hydrogen gas present in the intergalactic medium (IGM). This period in which the Universe transitioned from a cold and neutral state to a predominantly hot and ionized state is known as the Epoch of Reionization (EoR). LÄS MER

  5. 5. Efficient Spectrum Utilization of Uhf Broadcast Band

    Författare :Lei Shi; Jens Zander; Ki Won Sung; Linda Dolye; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TV White Space; CellTV; UHF Band; Spectrum; Electrical Engineering; Elektro- och systemteknik;

    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