Sökning: "Over-the-Air"

Visar resultat 21 - 25 av 29 avhandlingar innehållade ordet Over-the-Air.

  1. 21. Signal Processing Aspects of Massive MIMO

    Författare :Ema Becirovic; Erik G. Larsson; Emil Björnson; Christoph Studer; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Massive MIMO (multiple-input-multiple-output) is a technology that uses an antenna array with a massive number of antennas at the wireless base station. It has shown widespread benefit and has become an inescapable solution for the future of wireless communication. LÄS MER

  3. 22. Reverberation Chamber Characterizations for Passive and Active OTA Measurements

    Författare :Chen Xiaoming; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Reverberation chamber (RC) has drawn more and more attention as a multipath emulator over the past decade. It has been used for antenna efficiency measurements. It has also been used to measure diversity gain and multi-input multi-output (MIMO) capacity using multi-port antenna. LÄS MER

  4. 23. Efficient Backhauling in Cooperative MultiPoint Cellular Networks

    Författare :Tilak Rajesh Lakshmana; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Coordinated multipoint; scheduling; quantization errors; precoding; particle swarm optimization; stochastic optimization; decentralized architecture; prediction errors;

    Sammanfattning : The efficient use of the spectrum in cellular systems has given rise to cell-edge user equipments (UEs) being prone to intercell interference. In this regard, coordinated multipoint (CoMP) transmission is a promising technique that aims to improve the UE data rates. LÄS MER

  5. 24. Resource Allocation in Downlink Coordinated Multi-Point Systems

    Författare :Jingya Li; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; backhaul latency; Coordinated multi-point CoMP transmission; imperfect synchronization; fractional frequency reuse; resource allocation; general duality theory; imperfect channel state information; inter-cluster interference coordination;

    Sammanfattning : The raised user expectations of quality of service and the rapid growth of the data traffics impose a great challenge for mobile communication systems. The performance, e.g., the spectrum efficiency, peak data rate, cell-edge data rate, of current cellular systems ismainly limited due to the presence of inter-cell interference. LÄS MER

  7. 25. Characterization of Small Antennas & Wireless Devices for MIMO Systems in Rich Isotropic Multipath & Random Line-of-Sight

    Författare :Ahmed Hussain; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MIMO; Rayleigh; reverberation chamber; random LOS; RIMP; LTE; OTA;

    Sammanfattning : The current thesis is about over-the-air (OTA) performance characterization of wireless terminals in rich isotropic multipath (RIMP) environment as well as in pure line-of-sight (LOS) environment while not ignoring the random positions and orientations of the mobile terminals due to randomness of the user. The latest mobile wireless terminals such as iPhone and iPad can be used in any random position and orientation thereby making the received LOS-component toappear as a random voltage at the antenna ports. LÄS MER