Channel capacity for various materials of partitions in indoor ultra wideband communication system with multiple input multiple output

[[abstract]]In this paper, an image based ray-tracing model is used to calculate the channel capacity for various materials of partitions in indoor ultra wideband (UWB) system with multiple input multiple output (MIMO). The material parameters of the partitions such as dielectric constant and conductivity are both dependent on operation frequency in our calculations for more precise results. The effects of various materials of partitions on 2times2 MIMO UWB system are simulated for different signal-to-noise ratio (SNR).[[conferencetype]]國際[[conferencedate]]20070926~20090928[[iscallforpapers]]Y[[conferencelocation]]Tashkent, Uzbekista

Spin alignment of vector meson in e+e- annihilation at Z0 pole

We calculate the spin density matrix of the vector meson produced in e+e- annihilation at Z^0 pole. We show that the data imply a significant polarization for the antiquark which is created in the fragmentation process of the polarized initial quark and combines with the fragmenting quark to form the vector meson. The direction of polarization is opposite to that of the fragmenting quark and the magnitude is of the order of 0.5. A qualitative explanation of this result based on the LUND string fragmentation model is given.Comment: 15 pages, 2 fgiures; submitted to Phys. Rev.

Spin Alignment of Vector Meson in High Energy Reactions

The recent data on the polarization of vector meson at LEP show that the vector mesons favor the helicity zero state. We calculate the helicity density matrix of vector meson which contains a polarized fragmenting quark by adding the spin of the fragmenting quark and that of the antiquark created in the fragmentation. The data at LEP imply a significant polarization for the antiquark in the opposite direction as that of the fragmenting quark. We extend the calculations to other reactions and make predictions for vector mesons in deeply inelastic lepton-nucleon scatterings and polarized $pp$ collisions.Comment: 4 pages,3 figures, Talk given at 3rd Circum-Pan-Pacific Symposium on "High Energy Spin Physics", Beijing, China, Oct.8-13, 200