CORREIA FILHO, L. A.; CORREIA FILHO, LUIS ALVES.; http://lattes.cnpq.br/4530064104275973; CORREIA FILHO, Luis Alves.
Resumo:
This work constitutes with the study of an algorithm to estimate the direction of arrival
(DoA) of signals using Independent Component Analysis (ICA). The DoA estimation is
applied in several problems with electromagnetic sources, such as sensor networks
and processing of smart antennas, being a topic investigated due to applications in
Internet of Things (IoT) and in the fifth generation of cellphones (5G). The classical
methods used to obtain DoA, as the Multiple Signal Classification (MUSIC) and the
Estimation of Signal Parameters via Rotational Invariance Techniques (ESPRIT) have
some restrictions. The detection of overlapping sources (which has the same DoA) is
one limitation of these methods, since they can not estimate the presence of more than
one source if they radiate in the same direction. Another constraint is that these
methods require more sensors than electromagnetic sources to safely estimate DoA.
In the classical ICA formulation was added the term related to phase delay to the signal
matrix. This parameter is subsequently used to determine the direction of arrival. In
this work, simulations were performed comparing the ICA method studied with the
classical methods MUSIC and ESPRIT. It was possible to validate that the ICA can
overcome the restrictions of the classic methods in relation to the estimation of
overlapping sources and to work with a smaller number of sensors, that is, the same
number of sensors and sources. Measurements were made with antennas to
experimentally confirm the effectiveness of the extension of the ICA method to detect
electromagnetic sources in these situations. Although the technique presents a greater
error compared to algorithms like MUSIC, the algorithm was able to detect the DoA of
all the sources in adverse situations, besides being able to relate each DoA to its
respective electromagnetic source.