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Plenary
Lecture
An Iterative Kalman-like Algorithm with no Requirements
for Noise and Initial Conditions
Professor Yuriy S. Shmaliy
Department of Electronics
DICIS, Guanajuato University,
Salamanca, 36855, Mexico
E-mail:
shmaliy@salamanca.ugto.mx
Abstract: The term "Kalman-like" or "Kalman-type" is
commonly used whenever the standard linear Kalman
filtering algorithm is modified to estimate state of the
nonlinear model, under unknown initial conditions, in
the presence of nonwhite or multiplicative noise
sources, etc. In such improper applications for the
Kalman filter, the Kalman-like one is designed to save
the recursive structure, while connecting the algorithm
components with the model in different ways. Because
there can be found an infinity of the Kalman-like
solutions depending on applications, we encounter a
number of propositions suggesting some new qualities
while saving (or not deteriorating substantially) the
advantages of the Kalman filter: accuracy, fast
computation, and small memory. The extended and
unscented algorithms are among the widely recognized
Kalman-like ones suitable for nonlinear problems. Nahi
proposed a modification for uncertain observations by
including the multiplicative noise component to the
measurement matrix. For hidden Markov trees, the
efficient restoration Kalman-like algorithm was
discussed by Basseville et al. Implying nonlinear
modeling for hidden Markov chains, the Kalman filter was
modified by Baccarelli and Cusani to have the gain
dependent on the observations. Most recently,
Ait-El-Fquih and Desbouvries applied the Kalman-like
approach to triple Markov chains. We also meet a new
Kalman-like tracking algorithm applied to the
autoregressive channel process estimation with fading by
Stefanatos and Katsaggelos. Different kinds of the
Kalman-like algorithms can also be found in the area of
control. Becis-Aubrya et al, discussed the two-step one
with a switching gain matrix. Carli et al. employed the
concept of the centralized Kalman filter for state
estimation in the complex sensor networks, and the list
of the developments can be extended. There were also
proposed the iterative Kalman-like forms for the finite
impulse response (FIR) time invariant filters. Han,
Kwon, and Kim suggested a relevant algorithm for
deterministic control systems and Shmaliy derived an
algorithm for the p-shift unbiased FIR estimator.
This lecture introduces readers to the recently
developed p-shift general iterative linear Kalman-like
FIR estimation algorithm intended for filtering (p = 0),
prediction (p > 0), and smoothing (p < 0) of linear
discrete time-varying state-space models. The algorithm
is designed to have no requirements for noise and
initial conditions and thus has strong engineering
features. A solution is first found in a batch form and
then represented in the computationally efficient
iterative Kalman-like one with the following advantages
peculiar to FIR structures: guarantied bounded
input/bounded output (BIBO) stability, better robustness
against temporary model uncertainties and round-off
errors, and low sensitivity to noise and initial
conditions. It is shown that the estimator proposed
overperforms the Kalman one when 1) the noise
covariances and initial conditions are not known
exactly, 2) the noise constituents are not white
sequences, and 3) both the system and measurement noise
components need to be filtered out. Otherwise, the
Kalman-like and Kalman estimators produce similar
errors. A payment for this is a larger operation time
featured to averaging. These conclusions are supported
by extensive numerical investigations and comparisons
with the Kalman smoothing, filtering, and predictive
estimates of multistate space models. Examples of
applications are taken from signal and image processing,
clock synchronization, and control. If one still wonders
why the Kalman-like FIR algorithm ignoring noise and
initial conditions is able to provide errors similar or
even lower than in the Kalman one, then there is no
magic. Just recall the rule of thumb of averaging: the
estimate variance diminishes as a reciprocal of the
averaging interval irrespective of the model.
Brief Biography of the Speaker:
Dr. Yuriy S. Shmaliy is Full Professor of Electrical and
Electronics Engineering of the University of Guanajuato
(DICIS campus in Salamanca), Mexico. He received the
B.S., M.S., and Ph.D. degrees in 1974, 1976 and 1982,
respectively, from the Kharkiv Aviation Institute,
Ukraine, all in Electrical Engineering. In 1992 he
received the Doctor of Technical 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. Since 1993 to
1999, he has been a director-collaborator of the
Scientific Center "Sichron" (Kharkiv, Ukraine) working
in the field of precise time and frequency. Since 1999
to 2009, he has been with the Kharkiv National
University of Radio Electronics, and, since November
1999, he has been with the Guanajuato University of
Mexico. 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 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 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 Senior Member of IEEE and belongs
to several other professional Societies. 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. He is a founder and
organizer of the Int. Symposium on Precision Oscillators
in Electronics and Optics. He was multiply invited to
give tutorial, plenary, and seminar lectures. His
current interests include statistical signal processing,
optimal estimation, and stochastic system theory.
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