Sökning: "Cognitive networks"

Visar resultat 1 - 5 av 140 avhandlingar innehållade orden Cognitive networks.

  1. 1. Cognitive Radio Networks : Elements and Architectures

    Författare :Alexandru Popescu; Blekinge Tekniska Högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Cognitive radio network management; spectrum access; multiconstrained routing optimization; multi-dimensional adaptation; middleware;

    Sammanfattning : As mobility and computing becomes ever more pervasive in society and business, the non-optimal use of radio resources has created many new challenges for telecommunication operators. Usage patterns of modern wireless handheld devices, such as smartphones and surfboards, have indicated that the signaling traffic generated is many times larger than at a traditional laptop. LÄS MER

  3. 2. Distributed Detection in Cognitive Radio Networks

    Författare :Ahti Ainomäe; Mats Bengtsson; Tõnu Trump; Olav Tirkkonen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cognitive Radio; distributed estimation; distributed detection; Diffusion LMS; Diffusion Networks; Adaptive Networks; Spectrum Sensing; Energy Detection; Random Matrix; Largest Eigenvalue Detection.; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : One of the problems with the modern radio communication is the lack of availableradio frequencies. Recent studies have shown that, while the available licensed radiospectrum becomes more occupied, the assigned spectrum is significantly underutilized. LÄS MER

  4. 3. Performance Analysis of Cognitive Radio Networks with Interference Constraints

    Författare :Hung Tran; Blekinge Tekniska Högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cognitive Radio Networks; Spectrum Underlay Access; Interference Constraints; Cognitive Cooperative Radio Networks;

    Sammanfattning : To support the rapidly increasing number of mobile users and mobile multimedia services, and the related demands for bandwidth, wireless communication technology is facing a potentially scarcity of radio spectrum resources. However, spectrum measurement campaigns have shown that the shortage of radio spectrum is due to inefficient usage and inflexible spectrum allocation policies. LÄS MER

  5. 4. Improving user comprehension and entertainment in wireless streaming media : introducing cognitive quality of service

    Författare :Greger Wikstrand; Lars-Erik Janlert; Jerry Eriksson; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Multicast channels; Quality of Service; Cognitive QoS; Wireless LAN; Multiaccess Communication; IEEE 802.11; Displays; Mobile Communications; Video Coding; Tracking; Animation; Cognitive Psychology; Experience Design; Computer science; Datavetenskap;

    Sammanfattning : In future mobile networks service quality might be poor. A new measure is needed to be able to assess services in terms of their effectiveness and usefulness despite their lacking visual appeal. Cognitive Quality of Service is a way to measure the effectiveness in use of a networked service. LÄS MER

  7. 5. Secrecy in Cognitive Radio Networks

    Författare :Frederic Gabry; Mikael Skoglund; Merouane Debbah; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : With the considerable growth of wireless networks in recent years, the issue of network security has taken an important role in the design of communication devices and protocols. Indeed, due to the broadcast nature of these networks, communications can potentially be attacked by malicious parties, and therefore, the protection of transmitted data has become a main concern in today's communications. LÄS MER