Plenary
Lecture
Robustness of Unbiased FIR Estimators against Outliers
and Temporary Uncertainties
Professor Yuriy S. Shmaliy
Department of Electronics
DICIS, Guanajuato University
Salamanca, 36855, Mexico
E-mail:
shmaliy@salamanca.ugto.mx
Abstract: In this lecture, we examine recently
developed the p-shift finite impulse response (FIR)
unbiased estimator (UE) intended for filtering (p = 0),
p-step prediction (p > 0), and p-lag smoothing (p < 0)
of linear discrete time-varying state-space models. The
estimator is investigated for robustness in Gaussian and
non-Gaussian noise environments with outliers and
temporary uncertainties in a comparison to the Kalman
filter. The FIR UE algorithm is designed to have no
requirements for noise and initial conditions and thus
has strong engineering features. It is first presented
in a batch form and then developed in the
computationally efficient iterative Kalman-like one
having the guarantied bounded input/bounded output
(BIBO) stability, unlike the Kalman filter. Owing to the
imbedded BIBO stability and without any other special
solutions, such as those used in robust filtering, the
FIR UE is show to have better robustness than the Kalman
filter against the heavy-tailed noise and Gaussian noise
with outliers. It is also shown to have a bit better
robustness against temporary model uncertainties. Errors
in the Kalman-like FIR UE are compared to the error
bound (EB) specified via the noise power gain (NPG)
serving as a limiter of errors in transversal
estimators. We show that the EB specialized via the NPG
in the three-sigma sense can also be useful in Kalman
filtering. Examples of applications are taken from
signal and image processing, clock synchronization, and
control. Based upon these examples, we demonstrate that
the Kalman-like FIR UE overperforms the Kalman filter
one if the noise covariances and initial conditions are
not known exactly, the noise constituents are not white
sequences, and both the system and measurement noise
components need to be filtered out. Otherwise, the
errors are similar.
Brief Biography of the Speaker:
Dr. Yuriy S. Shmaliy is Full Professor in Electrical
Engineering of the University of Guanajuato, Mexico,
since 1999. He received the B.S., M.S., and Ph.D.
degrees in 1974, 1976 and 1982, respectively, from the
Kharkiv Aviation Institute, Ukraine. In 1992 he received
the Dr.Sc. degree from the Kharkiv Railroad Institute.
In March 1985, he joined the Kharkiv Military
University. He serves as Full Professor beginning in
1986 and has a certificate of Professor from the
Ukrainian Government in 1993. In 1993, he founded and,
by 2001, had been a director-collaborator of the
Scientific Center “Sichron” (Kharkiv, Ukraine) working
in the field of precise time and frequency. His books
Continuous-Time Signals (2006) and Continuous-Time
Systems (2007) were published by Springer, New York. His
book GPS-based Optimal FIR Filtering of Clock Models
(2009) was published by Nova Science Publ., New York. He
also contributed to several books with invited chapters.
Dr. Shmaliy has 262 Journal and Conference papers and 80
patents. He is IEEE Fellow; was rewarded a title,
Honorary Radio Engineer of the USSR, in 1991; was listed
in Marquis Who's Who in the World in 1998; was listed in
Outstanding People of the 20th Century, Cambridge,
England in 1999; and was listed in The Contemporary
Who’s Who, American Bibliographical Institute, 2003. He
is currently an Associate Editor of Recent Patents on
Space Technology. He is a member of the Organizing and
Program Committees of various Int. Symposia. His current
interests include statistical signal processing, optimal
estimation, and stochastic system theory.
|