An Improved SFBC Scheme Based on 4 Antennas

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An Improved SFBC Scheme Based on 4 Antennas

• ZTE Corperation
• 2007-09

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Introduction

• Transmit diversity based on Alamouti is broadly
  used in wireless communication systems
• SFBCCDD
• SFBCPSD
• SFBCFSTD
• STBCFSTD

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Alamouti scheme for 4 antennas

• Assuming the transmit symbols are

Each symbol can be with 2 order diversity
----Which can be improved
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Improved scheme

• We act a unitary matrix U on the coding matrix as
  followings

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Improved scheme

• Scheme diagram

Spatial-Frequency Block Coding Scheme based on
Mixing 4 Antennas
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Improved scheme

• Advantage of the improved scheme
• The Improved scheme making each symbol get
  diversity order more than 2!
• This method can be easily applied to 6 or 8
  antennas.
• Since we adopt unitary matrix U ,the receiver can
  be easily implemented- the inverse equals to the
  Hemmite transpose.

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Simulation Assumptions
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Simulation Assumptions

• Let the unitary matrix be Givens matrix

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Simulation Results

• UEs Velocity 3km/h

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Thanks!