EGEE 4110 Digital Signal Processing Lecture 4

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EGEE 4110Digital Signal ProcessingLecture 4

• Digital System Structures
• Professor Timothy Tuinstra

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Basic DSP Building Blocks
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Basic DSP Building Blocks
Note Delay blocks in DSP designs essentially
imply a memory register large enough to hold one
sample at whatever precision the architecture
requiresi.e. a delay is a memory element!
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Filter Interconnections

• The associative property of convolution allows us
  flexibility when we create digital systems.

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Filter Interconnections

• The distributive property of convolution also
  allows us flexibility when we create digital
  systems.

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Filter Structures

• Why do we care about filter structures?
• Study of filter structures gives us important
  insights into hardware implementations.
• Digital filters are straight-forward to implement
  on FPGA chips using VHDL, AHDL, or graphical
  interface
• Study of filter structures gives us important
  insights into software implementations
• C
• Fortran

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Structures for FIR filters

• Recall the difference equation for an FIR

• This FIR requires M locations in memory

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Structures for FIR filters
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Structure for IIR Filters (Systems)

• Recall the general difference equation for IIR
  filters

IIR portion
FIR portion
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Structure for IIR Filters
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