6223

381 دكتري

كارشناسي ارشد

برق

اصفهان: دانشگاه صنعتي اصفهان، دانشكده برق و كامپيوتر

1390

پانزده،143ص.: مصور،جدول،نمودار

ص.ع.به فارسي و انگليسي

محمدجواد اميدي

علي محمد دوست حسيني

21/6/90

حسين ضميري جعفريان، پاييز عزمي،محمد علي خسروي فرد

مهندسي برق و كامپيوتر

ID381 دكتري

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

Joint ICI IBI and IQ Imbalance Compensation for MIMO OFDM Systems in Doubly Selective Channels Mojtaba Beheshti Mojtaba beheshti@gmail com Date of Submission 2011 08 13 Department of Electrical and Computer Engineering Isfahan University of Technology Isfahan 84156 83111 IranSupervisor Mohammad Javad Omidi omidi@cc iut ac irAdvisor Ali Mohammad Doost Hoseini alimdh@cc iut ac irDepartment Graduate Program Coordinator Amir Borji Department of Electrical and Computer Engineering Isfahan University of TechnologyAbstract Time variations of a doubly selective channel and insufficient cyclic prefix CP length in anOrthogonal Frequency Division Multiplexing OFDM transmission system cause intercarrierinterference ICI and interblock interference IBI as significant limitations In the first part of thisthesis we investigate the problem of joint ICI and IBI mitigation in multiple input multiple outputOFDM MIMO OFDM systems We assume that the channel delay spread is larger than the CP andalso the channel varies within each OFDM block The doubly selective channel is modeled usingbasis expansion model BEM and four time domain equalizers are developed Also a frequency domain equalization approach is proposed to confront ICI IBI Practical implementation of MIMO OFDM systems also suffers from the effect of In phase Quadrature phase IQ imbalance in theanalog front end section This phenomenon can severely degrade the achievable performance In thesecond part of this thesis we study the digital compensation of both the transmitter and receiver IQimbalances in MIMO OFDM transmission over doubly selective channels In particular we employthe BEM to develop a novel IQ formulation for a time varying channel Using this formulation wesuggest a general scheme to jointly mitigate the IQ imbalance and channel time variation effects Animportant feature of the proposed equalizers is that no bandwidth expansion or redundancy insertionis required except for the CP Finally we provide simulation results over two classes of doublyselective wireless radio and underwater acoustic channels to illustrate the good performance of theproposed approaches KeywordsOFDM MIMO intercarrier interference interblock interference IQ imbalance equalization

محمدجواد اميدي

علي محمد دوست حسيني

حسين ضميري جعفريان، پاييز عزمي،محمد علي خسروي فرد