| Abstract: |
In this talk, we will present some of our results on antenna subset
selection for wireless communications systems that employ multiple
transmit and receive antennas. We assume that the channel is
characterized by quasi-static Rayleigh flat fading, and the channel
state information (CSI) is exactly known at the receiver. We also
assume that selection is available only at the receiver, and it is
based on the instantaneous signal-to-noise ratio at each receive
antenna. We analyze the performance of such systems by deriving
explicit upper bounds on the pairwise error probability (PEP). This
performance analysis shows that (i) by selecting the set of antennas
that observe the largest instantaneous signal-to-noise ratio, one can
achieve the same diversity gain as the one obtained by using all the
receive antennas, provided that the underlying space-time code has
full spatial diversity, and (ii) in the case of rank-deficient
space-time
codes, the diversity gain may be dramatically reduced when antenna
selection is used. In addition, based on the upper bounds derived,
we describe code design principles suitable for antenna selection.
Specifically, for systems with two transmit antennas, we design
space-time codes that perform better than the known ones when
antenna selection is employed. Finally, we present numerical
examples and simulation results that validate our analysis and
code design principles.
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| Biography: |
Israfil Bahceci received the B.S. degree from Bilkent University in
1999, and the M.S. degree from Arizona State University, Tempe, in 2001,
all in electrical engineering. He is currently pursuing his Ph.D. at
Georgia Tech with Prof. Altunbasak. Mr. Bahceci's current research
interests are in digital communications, wireless and mobile
communications, channel coding, turbo codes, coding for wireless
communications, coding for multiaccess channels, sensor networks, and
bioinformatics.
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