The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform

Fuchiarng Che - One of the best experts on this subject based on the ideXlab platform.

  • a reconfigurable quadri Polarization Diversity aperture coupled patch antenna
    IEEE Transactions on Antennas and Propagation, 2007
    Co-Authors: D Y Lai, Fuchiarng Che
    Abstract:

    We present a novel reconfigurable quadri-Polarization Diversity aperture-coupled patch antenna which can provide four Polarization states. By controlling the dc bias voltage of the pin-diodes on the feeding network, we can reconfigure the proposed antenna to provide a pair of orthogonal linear Polarizations and a pair of orthogonal circular Polarizations. Numerical and experimental results validate our design. This novel antenna provides potential Polarization Diversity features for wireless local area networks and multiple-input multiple-output systems

D Y Lai - One of the best experts on this subject based on the ideXlab platform.

  • a reconfigurable quadri Polarization Diversity aperture coupled patch antenna
    IEEE Transactions on Antennas and Propagation, 2007
    Co-Authors: D Y Lai, Fuchiarng Che
    Abstract:

    We present a novel reconfigurable quadri-Polarization Diversity aperture-coupled patch antenna which can provide four Polarization states. By controlling the dc bias voltage of the pin-diodes on the feeding network, we can reconfigure the proposed antenna to provide a pair of orthogonal linear Polarizations and a pair of orthogonal circular Polarizations. Numerical and experimental results validate our design. This novel antenna provides potential Polarization Diversity features for wireless local area networks and multiple-input multiple-output systems

David A. Sanchez-hernandez - One of the best experts on this subject based on the ideXlab platform.

  • Evaluation of True Polarization Diversity for MIMO Systems
    IEEE Transactions on Antennas and Propagation, 2009
    Co-Authors: Juan F. Valenzuela-valdes, Miguel A. Garcia-fernandez, A.m. Martinez-gonzalez, David A. Sanchez-hernandez
    Abstract:

    MIMO systems where multipath fading is only partially correlated could use Polarization Diversity to provide a higher Diversity gain. Recent letters have proposed the use of tri-polarized antennas and a novel true Polarization Diversity (TPD) scheme. In this paper, the full potential of TPD is evaluated with both simulations and measurements and compared to conventional orthogonal Polarization Diversity (OPD). MIMO system performance with respect to capacity and Diversity gain is obtained through the use of multimode-stirred chambers for both isotropic and non-isotropic environments. Simulated and measured results in over 591 different MIMO systems show that TPD outperforms conventional OPD for reduced volumes. Likewise, it has been demonstrated that TPD can be effectively combined with spatial Diversity to nearly double the Diversity gain and MIMO capacity for the same available handset volume.

Luca Simone Ronga - One of the best experts on this subject based on the ideXlab platform.

  • Polarization Diversity for multiband UWB systems
    Signal Processing, 2006
    Co-Authors: Fabrizio Argenti, Tiziano Bianchi, Lorenzo Mucchi, Luca Simone Ronga
    Abstract:

    Ultra-wideband (UWB) transmission provides a fast local range wireless connection using the same frequency spectrum assigned to other narrowband communication standards. A precise knowledge of the indoor transmission channel is necessary to obtain high performance. Several channel models have been presented in the literature, but normally without considering the distortion effect caused by a real UWB antenna. A detailed antenna model shows that the radiation pattern varies with frequency, i.e., different receiver positions and antenna orientations result in different antenna frequency responses. In order to obtain a more uniform coverage over the indoor area, two transmitting antennas with orthogonal Polarization can be used. The receiver can use a single antenna whose orientation and position is arbitrary within the coverage area, resulting in a special case of a 2:1 MISO system in which a space-time encoding is used at the transmitter. The target is to employ the Polarization Diversity to obtain a constant quality of symbol detection while the receiver moves around in the coverage area. The proposed Polarization Diversity scheme is applied in an UWB multiband scenario and it is compared to both a single antenna scheme and a classical space Diversity scheme employing a single polarized antenna array.

Juan F. Valenzuela-valdes - One of the best experts on this subject based on the ideXlab platform.

  • True Polarization Diversity for non isotropic scenarios
    2010
    Co-Authors: Juan F. Valenzuela-valdes, Juan D. Sanchez-heredia, Miguel A. Garcia-fernandez
    Abstract:

    MEMO systems where multipath fading is only partially correlated could use Polarization Diversity to provide a higher Diversity gain. Recent letters have proposed the use of tri-polarized antennas and a novel true Polarization Diversity (TPD) scheme. In this paper, the full potential of TPD is evaluated with both simulations and measurements and compared to conventional orthogonal Polarization Diversity (OPD). MIMO system performance with respect to capacity and Diversity gain is obtained through the use of multimode-stirred chambers for both isotropic and non-isotropic environments. Simulated and measured results in over 591 different MIMO systems show that TPD outperforms conventional OPD for reduced volumes. Likewise, it has been demonstrated that TPD can be effectively combined with spatial Diversity to nearly double the Diversity gain and MIMO capacity for the same available handset volume.

  • Evaluation of True Polarization Diversity for MIMO Systems
    IEEE Transactions on Antennas and Propagation, 2009
    Co-Authors: Juan F. Valenzuela-valdes, Miguel A. Garcia-fernandez, A.m. Martinez-gonzalez, David A. Sanchez-hernandez
    Abstract:

    MIMO systems where multipath fading is only partially correlated could use Polarization Diversity to provide a higher Diversity gain. Recent letters have proposed the use of tri-polarized antennas and a novel true Polarization Diversity (TPD) scheme. In this paper, the full potential of TPD is evaluated with both simulations and measurements and compared to conventional orthogonal Polarization Diversity (OPD). MIMO system performance with respect to capacity and Diversity gain is obtained through the use of multimode-stirred chambers for both isotropic and non-isotropic environments. Simulated and measured results in over 591 different MIMO systems show that TPD outperforms conventional OPD for reduced volumes. Likewise, it has been demonstrated that TPD can be effectively combined with spatial Diversity to nearly double the Diversity gain and MIMO capacity for the same available handset volume.

  • Reduction of 3×3 MIMO volume requirements by using true Polarization Diversity techniques
    2007 European Conference on Wireless Technologies, 2007
    Co-Authors: Juan F. Valenzuela-valdes, A.m. Martinez-gonzalez, David Sanchez-hernandez
    Abstract:

    Polarization Diversity techniques have not received as much attention as others due to the significant difference in mean signal level between co-polarized and cross-polarized branches when one Polarization is transmitted. However, MIMO systems where the multipath fading is only partially correlated could use Polarization Diversity to provide a high Diversity gain. In this contribution, progressive (hue) Polarization Diversity performance for 3times3 MIMO systems under Rayleigh-fading environments is evaluated through simulations and measurements in a reverberation chamber. True Polarization Diversity was found to be as significant as spatial Diversity at improving Diversity gain, and hence MIMO system capacity.