7988

7423

كارشناسي ارشد

مخابرات سيستم

اصفهان: دانشگاه صنعتي اصفهان، دانشكده برق و كامپيوتر

1391

نه،100ص. مصور،جدول،نمودار

ص.ع.به فارسي و انگليسي

علي محمد دوست حسيني، ابوالقاسم زيد آبادي نژاد

7/7/92

مهندسي برق و كامپيوتر

ID7423

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

222 Characterization of MIMO Non Isotropic Wireless Propagation Channels Ali Rafiei a rafiei@ec iut ac ir Date of Submission 2013 03 18 Department of Electrical and Computer Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language FarsiSupervisors Ali Mohamad Doost hoseini alimdh@cc iut ac ir Abolghasem Zeidaabadi Nezhad zeidabad@cc iut ac irAbstract In recent years the increasing demand for high data rates and the limited available bandwidth havemotivated the investigation of wireless systems that efficiently exploit the spatial dimension An interestingtrend in wireless communications that is spatially efficient employs multiple antennas at both transmitter andreceiver This trend is called multiple input multiple output MIMO communications The application ofantenna arrays for wireless cellular systems has received much attention as they improve the coverage andcapacity of such systems by combating interference and fading Also by exploiting antenna arrays at both thetransmitter and receiver the capacity of wireless channels can be increased significantly In order to designhigh performance multiple input multiple output MIMO wireless systems and to predict the impact ofrandom multipath propagation on fading it is necessary to have accurate and reliable MIMO channel models In this thesis we have derived cross correlation function CCF between the space time frequency STF transfer functions of two sub channels of an outdoor non isotropic environment with non omnidirectionalantennas using the plane wave propagation model when the moving system MS has a constant speed MostMIMO channel models employ certain geometries for the scatterers around the receiver to describenon isotropic propagation Alternatively in this thesis we have described and simulated such a channel withanalytical stochastic approach using Von Mises probability distribution function to describe the non isotropicpropagation The CCF is expressed in a closed and easy to use form as a function of propagation environmentand antenna arrays parameters This cross correlation function is comprised of two terms either of whichrepresents the impact of the wireless channel around the transmitter the receiver and along the channel interms of time carrier frequency and location of the antenna arrays elements Finally in order to examine thedescription and study the effects of the propagation and antennas parameters as well as the motion of thereceiver on the CCF the expression for the stationary channel power spectral density function is calculated andillustrated Keywords MIMO channel models Cross correlation function CCF Non omnidirectional antennaarray Power Spectrum Density function PSD Von Mises distribution function

علي محمد دوست حسيني، ابوالقاسم زيد آبادي نژاد