Signals and Systems

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Signals and Systems

• Lecture 18
• FIR Filters

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Today's lecture

• FIR Structures Building Blocks
• Linear Time-invariant Systems
• System Properties
• Linearity
• Time-invariance
• Filters as Building Blocks

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Hardware Structures
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Linear Time-invariant Systems
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Linear Time-invariant Systems FIR Filters
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Overview
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Digital Filtering
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Building Blocks
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LTI Convolution Sum
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Convolution Example
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System Properties
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Time Invariance
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Testing Time-Invariance
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Examples of Time-Invariance

• Square Law system
• yn xn 2
• Time Flip system
• yn x- n
• First Difference system
• yn xn - xn-1
• Practice Prove the system given Exercise 5.9 is
  not time-invariant

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Linear System
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Testing Linearity