9557

8824

كارشناسي ارشد

برق - مخابرات سيستم

اصفهان: دانشگاه صنعتي اصفهان، دانشكده برق و كامپيوتر

1393

[يازده]،82ص.: جدول،نمودار

ص.ع.به فارسي و انگليسي

محمد صادق فاضل

29/11/93

علي محمد دوست حسيني

مهندسي برق و كامپيوتر

ID8824

AF Two Way Relay placement in Large Scale Fading in the Sense of Minimum Outage Probability Rasoul Bayezi Kuli R Bayezi@ec iut ac ir Date of Submission 20 09 2014 Department of Electrical and Computer Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language FarsiSupervisor M S Fazel Fazel@cc iut ac irAbstract Cooperative relay communication technique is a new approach to obtain spatial diversity Also this techniqueis considered as an efficient way to enhance reliability and coverage of communication networks In one wayrelay systems with three nodes namely source destination and a third node relay it has been shown that thepresence of large scale fading affects the relay optimum position in the sense of minimum outage probability Therefore the joint effects of path loss and correlated shadowing with Rayleigh fading on Amplify andForward AF one way relay system has been studied Even an optimal relay placement algorithm wasdeveloped in order to obtain minimum outage probability in high signal to noise ratios The results indicatedthat the optimal relay placement is a function of the large scale fading channel statistics In this thesis westudy the effects of large scale channel fading on two way relay systems with AF protocol We show that thelarge scale channel conditions is affective on finding optimal relay placement in two way relay systems inorder to minimize outage probability of each user too At any of four scenarios of two way relay systems inthe presence of correlated shadowing and path loss we provide an approximation to the outage probability ofeach user for high signal to noise ratios and we obtain optimum relay placement based on thisapproximations for each user It should be noted that in this thesis due to the high complexity of problem weassume correlation coefficients between shadowing channels to be constant and independent of anglebetween lines connecting nodes According to results obtained for each scenario it can be shown ifcorrelation coefficients of shadowing channels are constant optimal relay placement is on the straight lineconnecting users It can be seen that type of poly phases scenarios of two way relay systems is affective onoutage probability performance of each user and consequently on optimal relay placement Also based ontwo criterions for outage probability of the whole multiuser system we evaluate performance of each poly phases scenario in two way relay system with the mentioned channel conditions The results suggest that thesame channel statistics for each poly phases scenario in two way relay systems with AF protocol gives thesame optimal point for relay Keywords Cooperative Relaying Communication Two Way Relaying Achievable Rate Outage Probability Correlated Shadowing Relay

محمد صادق فاضل

علي محمد دوست حسيني