Subspace tracking for nested arraysSubspace tracking for nested arraysΠαρακολούθηση υποχώρου για ένθετες συστοιχίες κεραιών
Διπλωματική Εργασία
Diploma Work
2016-07-252016enIn radar, sonar, and mobile communications, the estimation of the directions from which multi-
ple signals arrive at a point is called the direction of arrival (DoA) estimation problem and, over
the past decades, has been performed often through uniform linear arrays (ULAs) in conjunc-
tion with high-resolution subspace-based algorithms. Such techniques, however, have limited
capability of the number of directions they can estimate; if the ULA consists of N antenna
elements, then high-resolution subspace-based algorithms can estimate the directions of up to
N − 1 signals. To increase this number, a novel structure that consists of N antenna elements
and enables the estimation of O (N^2 ) signal directions has been developed recently. It lies on
specific nonuniform-array structures which are called nested arrays.
In this thesis, we first overviewed the structure and properties of nested arrays and eval-
uated their performance through computer simulations. We observed that the nested arrays
with conventional subspace-based signal-processing algorithms can offer high performance but
require high complexity, which makes them impractical for real-time applications. Then, we
developed novel subspace tracking techniques for nested arrays that have lower complexity,
are proven to converge to the optimal, subspace-based estimator, and are capable of tracking
changes in the directions of the arriving signals (for example, when a source is moving with
respect to the array receiver).http://creativecommons.org/licenses/by/4.0/Πολυτεχνείο Κρήτης::Σχολή Ηλεκτρολόγων Μηχανικών και Μηχανικών ΥπολογιστώνFountoulakis_Emmanouil_Dip_2016.pdfChania [Greece]Library of TUC2016-07-25application/pdf665.8 kBfree
Fountoulakis Emmanouil
Φουντουλακης Εμμανουηλ
Karystinos Georgios
Καρυστινος Γεωργιος
Bletsas Aggelos
Μπλετσας Αγγελος
Digalakis Vasilis
Διγαλακης Βασιλης
Πολυτεχνείο Κρήτης
Technical University of Crete
Signal processing