Combination of SFBC and SM

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Combination of SFBC and SM

• Ph.D. Student Nicola Marchetti
• Wireless Network Group
• Center for TeleInFrastruktur
• Aalborg University

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Ph.D. Goal
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Problem Definition
Goal
Constraint
4
Time Plan
5
Problem Set 1
Problem set 1 Find suitable hybrid diversity
and multiplexing scheme 1a. SFBC-SM-OFDMA (April
2005) Transmission structure Receiver according
to paper 1 Receiver according to paper
2 Linear receiver polar decomposition, QR/QL
decomposition Comparison with SFBC-OFDMA and
SM-OFDMA Comparison with STBC-SM-OFDMA in time
and frequency selective environment 1b.
CDD-SM-OFDMA (May 2005) Transmission
structure Receiver according to paper 1
Receiver according to paper 2
Comparison with CDD-OFDMA and SM-OFDMA
Comparison with STBC-SM-OFDMA and SFBC-SM-OFDMA
in time and frequency
selective environment
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Further Steps PS 2
Problem set 2 Selection of transmit diversity
techniques
(June-August 2005) 2a. Different transmit
diversity techniques (Alamouti, Tarokh,
Jafarkhani) 2b. Different diversity conditions
(Frequency diversity, Multi-user diversity,
Receive diversity) 2c. Different channel
conditions for both indoor and outdoor
(uncorrelated spatial channels in Rayleigh,
correlated spatial channels in Rayleigh,
Ricean) 2d. Space and frequency diversity
comparison (among DSA-SISO, static Tx
diversity, static Rx diversity, SCH-MISO,
SCH-SIMO)
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Further Steps PS 3

• Problem set 3
• Diversity and multiplexing tradeoff
• (September-December 2005)
• Comparison among diversity only systems
• Comparison among SM only systems
• Comparison among diversity and hybrid (diversity
  SM) systems
• based on the following algorithms
• Minimum Euclidean distance of received
  constellation points
• Received SNR as in paper 2
• SVD of the received signal as in paper 3

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Further Steps PS 4

• Problem set 4
• Diversity and multiplexing tradeoff in Latin
  square MIMO
• (September-December 2005, after completion of
  Problem set 3)
• Establish the Latin square MIMO scheme
• Show the tradeoff as developed in Problem set 3

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Further Steps PS 5 PS 6
Problem set 5 Extension of the previous work
to Heterogeneous Terminals with QoS
considerations (January-December
2006) Problem set 6 Extension of the
previous work to the up-link case (if there is
time)
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Current Work (1)
Problem set 1 Find suitable hybrid diversity and
multiplexing scheme 1a. SFBC-SM-OFDMA (April
2005) Transmission structure (Done) Receiver
according to paper 1 (Done) Receiver according
to paper 2 (In Progress) Linear receiver polar
decomposition, QR/QL decomposition (In
Progress) Comparison with SFBC-OFDMA and SM-OFDMA
(extension to Multi-user case) Comparison with
STBC-SM-OFDMA in time and frequency selective
environment
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Current Work (2)

• Paper 1 LS, MMSE, ZF ?
• extension to f-domain
• Paper 2 Successive cancellation (BLAST) ?
• extension to f-domain
• Polar, QR/QL decomposition ? applied to SM
  SFBC

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Motivation (1)
Multi-Antenna to get Diversity

• Multiple antennas can provide diversity gain
  via optimal/suboptimal combining
• (Tx Diversity, Rx Diversity) ? SFBC (Tx
  Diversity)
• Premise is to send same (weighted) input on
  each TX antenna, and combine at
• RX antennas (maximum Diversity gain NTNR)
• SNR maximized via MRC of multiple inputs and
  outputs low BER

a1x
b1
h11
h12
h13
X
b2
h21
gxn
a2x
h22
X
h23
h31
X
a3x
h32
b3
h33
Choose (ai), (bi) to maximize SNR output
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Motivation (2)
Multi-Antenna to get Spatial Multiplexing

• Multiple antennas can provide multiplexing gain
  through
• channel decomposition
• 1. CSI available at Tx (SVD/AMC-MIMO)
• 2. CSI not available at Tx (V/D-BLAST) ?
  V-BLAST
• Transform MIMO channel into multiple single
  antenna channels
• Maximum Capacity (multiplexing) gain of min (NT ,
  NR)
• Channel SNRs may be low (high BER)

h11
l1
h12
Matrix Transformation
h13
h21
h22
l2
h23
h31
h32
l3
h33
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Motivation (3)
Diversity Multiplexing Trade-off 4 (Single
User case)
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Motivation (4)

• Try to achieve simultaneously
• diversity and multiplexing gain,
• optimizing the trade-off

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References
1 X. Zhuang, F.W. Vook, S. Rouquette-Leveil, K.
Gosse, Transmit diversity and spatial
multiplexing in four-transmit-antenna OFDM,
ICC 2003 2 C.-B. Chae, M. Katz, C. Suh H.
Jeong, Adaptive spatial modulation for
MIMO-OFDM, WCNC 2004 3 L.
Giangaspero, L. Agarossi, G. Paltenghi, S.
Okamura, M. Okada, S. Komakil, Co-channel
interference cancellation based on MIMO OFDM
systems, IEEE Wireless Communications,
Dec 2002 4 L. Zheng, D.N.C. Tse,
Diversity and Multiplexing A Fundamental
Tradeoff in Multiple-Antenna Channels,
IEEE Transactions on Information Theory, May
2003
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Thanks TakDankeschoenGrazieMerciGraciasObrig
adoArigatoDhanyawad