Smart Antenna Rashmikanta Dash Regd.no:0601209202 ETC-A-52

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Smart Antenna Rashmikanta
Dash Regd.no0601209202 ETC-A-52
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OUTLINE

• Introduction
• What is Smart Antenna ?
• Why Smart Antenna ?
• How Smart Antenna works ?
• ULA
• UCA
• Conclusion

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Introduction

• Rapid growth of wireless communication
• Multi-services requirement
• Effective usage of frequency band
• Classic antennas are omni-directional
• smart antenna

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What is Smart Antenna ?

• Concept of SDMA system
• Arrange in a particular geometric form
• Use few methods to change EM wave pattern
• Switched beam system
• Adaptive antenna system

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Switched beam system
?select one of several beams to enhance received
signals
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Adaptive antenna system
?adaptive beam system can adjust its antenna
pattern to enhance the desired signal ?null or
reduce interference ?collect correlated multipath
power
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Why Smart Antenna

• Higher capacity (traffic/area)
• Better transmission quality and/or coverage

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Why Smart Antenna

• Reduction of transmitter power
• Reduction of delay spread
• Accurate user position estimation

Fixed cell shape
Dynamic cell shape
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Limiting effects of the wireless channel

• Multi-path propagation gives rise to
• fading
• inter-symbol interference
• time variation of signals
• Co-channel interference gives rise to
• increased noise level and hence greater errors

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Multi-path propagation

• Multipath components suffer different delays
• This gives rise to ISI
• reject or stimulate multipath components by
  changing their radiation patterns
• significantly reduce the requirements of
  equalization and/or increase CINR

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Co-channel interference

• Interference from other directions than wanted
  user
• suppress unwanted user by placing nulls in
  directions of unwanted signals
• improved transmission quality and/or system
  capacity

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How Smart Antenna works

• Uniform Linear Array geometry
• Uniform Circular Array geometry

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Uniform Linear Array geometry
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Base-band signal
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Uniform Circular Array geometry
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Conclusion

• Smart Antenna offer new ways to combat and/or
  exploit the spatial channel
• Smart Antennas reduce co-channel interference,
  improve BER performance and hence capacity

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THANK YOU..