Performance analysis of direction-of-arrival estimation algorithms in the presence of array imperfections and multipath for different antenna array geometries /

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2014
Çalışkan, Mustafa
Direction of Arrival (DOA) Estimation is an important topic in signal processing. In this thesis, DOA estimation is considered when there are gain/phase mismatches, mutual coupling for the antennas and multipath signals are observed. In the first part, DOA estimation for uniform linear array (ULA) in the presence of mutual coupling is considered. Different methods in the literature are investigated and a promising solution for this case [1] is implemented. Auxiliary sensors are used and MUSIC algorithm is employed for both DOA and mutual coupling coefficient estimation. This method has extensions for two dimensional case and hence the same problem is considered for uniform rectangular (URA) array. The simulation results show that DOA estimation in 2D array can be effectively done in case of mutual coupling. In case of both gain/phase mismatch and mutual coupling, a self-calibration method is implemented where gain/phase mismatch and mutual coupling are estimated iteratively for DOA estimation. Different array geometries are considered for the performance evaluation. The benefit of exploiting prior-knowledge for DOA estimation is considered. In this case, there are some known sources as well as unknown ones. In addition, source signals are correlated. Constrained-MUSIC (C-MUSIC) [2] , Prior-knowledge based DOA estimation (PLEDGE)[3], Prior-Exploiting Orthogonally Weighted Direction Estimator(POWDER) [4], and Forward-backward spatial smoothing and MUSIC (FBSS-MUSIC) [5] algorithms are implemented and compared. The scenario is also extended to include mutual coupling and multipath.

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Citation Formats
M. Çalışkan, “Performance analysis of direction-of-arrival estimation algorithms in the presence of array imperfections and multipath for different antenna array geometries /,” M.S. - Master of Science, Middle East Technical University, 2014.