Sökning: "radio"

Visar resultat 21 - 25 av 1095 avhandlingar innehållade ordet radio.

  1. 21. Generalized Bandpass Sampling Receivers for Software Defined Radio

    Författare :Yi-Ran Sun; Svante Signell; Markku K. Renfors; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Radio receivers; Software Defined Radio SDR ; uniform nonuniform sampling; reconstruction; bandpass sampling; noise aliasing; sampling jitter; generalized bandpass sampling; complex signal processing; complex FIR and IIR filter design; Switched-Capacitor SC circuit; Electrical engineering; Elektroteknik;

    Sammanfattning : Based on different sampling theorem, for example classic Shannon’s sampling theorem and Papoulis’ generalized sampling theorem, signals are processed by the sampling devices without loss of information. As an interface between radio receiver front-ends and digital signal processing blocks, sampling devices play a dominant role in digital radio communications. LÄS MER

  3. 22. Generalized Frequency Hopping in Cellular Radio Systems

    Författare :Mikael Gudmundson; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Cellular radio systems; mobile radio systems; random channel assignment; OFDM; spread spectrum; frequency hopping; spectral efficiency; Information technology; Informationsteknik; SRA - ICT; SRA - Informations- och kommunikationsteknik;

    Sammanfattning : .... LÄS MER

  4. 23. Frisk och stark med skolradion : Pedagogik och retorik i hälsoprogram 1930-1959

    Författare :Titti Forsslund; Karin Stigbrand; Stockholms universitet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Rhetoric; school radio; educational broadcasting; history; pedagogy; health; SOCIAL SCIENCES; SAMHÄLLSVETENSKAP; Journalistik; Pedagogik;

    Sammanfattning : This dissertation deals with the history of the Swedish School Radio Broadcasting service from its start in the end of the 1920s through the 1950s. The focus of the research is radio programmes for health education. LÄS MER

  5. 24. Dielectrically Loaded Quad-ridge Flared Horns for Ultra Wideband Reflector Feed Applications in Radio Astronomy

    Författare :Jonas Flygare; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dielectric loaded antennas; dielectric materials; reflector antenna feeds; radio astronomy; ultra wideband antennas; quad-ridge flared horn qrfh ; radio receivers; horn antennas; broadband antennas; aperture antennas.;

    Sammanfattning : Reflector-based radio telescopes are used as tools for observations in both radio astronomy and space geodesy. To observe the weak sources in space, highly sensitive receivers, fronted by optimized reflector feeds, are therefore needed. LÄS MER

  7. 25. Radio Network Planning and Resource Optimization : Mathematical Models and Algorithms for UMTS, WLANs, and Ad Hoc Networks

    Författare :Iana Siomina; Di Yuan; Peter Värbrand; Arie Koster; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; planning; optimization; wireless networks; radio resources; UMTS; WLAN; ad hoc; Telecommunication; Telekommunikation;

    Sammanfattning : The tremendous popularity of wireless technologies during the last decade has created a considerable expansion of wireless networks both in size and use. This fact, together with a great variety of mobile devices and numerous di®erent services that are becoming increasingly resourcedemanding, have attracted the attention of many researchers into the area of radio resource planning and optimization. LÄS MER