EE551 Seminar, 19 Wednesday 13:40,FENS G032
On
the Applications of Fractional Fourier Transform in Time-Frequency
Signal
Processing
Prof.
Lütfiye Durak
Yıldız Technical University, Istanbul
Abstract:
The fractional Fourier transform (FrFT) is a generalization of the
ordinary Fourier transform with an order
-or power- parameter of a. The first-order FrFT is the ordinary Fourier
transform and the zeroth-order FrFT is the function itself. Fractional
Fourier
domains are the set of all domains which interpolate between time and
frequency. The FrFT has found many
applications in the field of signal processing, time-frequency
analysis,
communications, optics, and image processing. This talk provides an
introduction to the FrFT and discusses some of its properties,
including its
effects on the time-frequency representations of signals as a special
case of
the linear canonical transforms. The time-frequency domain localization
of
signals by short-time Fourier transform (STFT) is characterized by
introducing
a novel generalized time-bandwidth product (GTBP) definition which is
an
extension of the time-bandwidth product on the fractional Fourier
domains. The
GTBP optimal STFT, which is a well-localized and high resolution
time-frequency
representation is introduced and its
computationally efficient form is presented. It provides optimal
results for
chirp-like signals which can be encountered in a variety of application
areas
including radar, sonar, seismic, biological signal processing and
communications. Furthermore, for signals with non-convex time-frequency
support, an improved time-frequency domain analysis is obtained through
chirp multiplication.
BIO: Lutfiye Durak
received the
B.Sc., M.Sc. and PhD. degrees in Electrical Engineering Department of
Bilkent
University, Ankara, Turkey, in 1996, 1999 and 2003, respectively. She
worked in
the Statistical Signal Processing Laboratory of Korean Advanced
Institute of
Science and Technology, KAIST until 2005. She was a visiting research
scholar
in the Department of Electrical and Computer Engineering of University
of
Pittsburgh for the summer of 2008. She is currently an assistant
professor in
the Electronics and Communications Engineering Department of Yildiz
Technical
University, Istanbul, Turkey. Her research interests are in
time-frequency
signal processing, adaptive signal processing,
statistical signal processing and communications theory.
19 Wednesday 13:40,FENS G032