ECE 445S Real-Time Digital Signal Processing Laboratory - Lecture 6

Lecture by Prof. Brian Evans

Announcements: Filtering Signals

Lecture

Lecture 6 slides on Infinite Impulse Response Filters is available in PowerPoint format.
- Spring 2025 Part 1
  - Board. First-Order IIR Filter Transfer Function
  - Board. Biquad Block Diagram
- Spring 2025 Part 2
  - Demo. Three-Domain Connections
- Spring 2025 Part 3
  - Board. Bandstop IIR Filter Design and Implementation
  - Board. Complex multiply takes four real multiplies
  - Board. Lowpass Magnitude Specification
- Demo. Interactive demo for filtering audio signals
- Handout. "Tapped Delay Line on C6700 DSP"
Lecture on IIR filters in spring 2014 on Video: Part 1, Part 2, Part 3, Part 4 and Part 5.

Supplemental Material

Fall 2024 marker board notes
- Fall 2024 Part 1
  - Transfer functions for first-order and second-order IIR filters
  - Run-Time Complexity for Biquad vs. Two First-Order Filters
  - Magnitude response for a notch filter
- Fall 2024 Part 2
  - Magnitude Response for Biquad Poles
  - Multiplying two floating-point numbers
- Fall 2024 Part 3
  - FIR Impulse responses with and without symmetry
Spring 2024 marker board notes
- Spring 2024 Part 1
  - Board. All-pole IIR Biquad Transfer Function
  - Board. Deriving an IIR biquad transfer function from a block diagram (after lecture)
  - Lecture notes by TA Alice Liu (Spring 2023)
- Spring 2024 Part 2
  - Board. First-order IIR filter frequency response by graphical method
  - Demo. Matlab code for IIR filter pole-zero configurations: Left - Middle - Right (slide 6-11)
  - Handout "All-pass Filters" (slide 6-11)
  - Board. Second-order IIR filters with real-valued poles and zeros
  - Demo. Time/frequency/z domain movies from DSP First, 2nd ed.
  - Lecture notes by TA Dan Jacobellis (Spring 2023)
- Spring 2024 Part 3
  - Handout. BIBO stability (slides 6-13 and 6-14)
  - Board. IIR Biquad Three Possible Regions Of Convergence
  - Tuneup. In-Lecture Assignment #2 on IIR Filter Design
  - Board. In-Lecture Assignment #2 on IIR Filter Design
  - Lecture notes by TA Alice Liu (Spring 2023)
- Spring 2024 Part 4
  - Handout. Parallel and Cascaded Realizations of IIR Filters
Fall 2023 marker board notes
- Part 1
  - Board. First-Order IIR Filter Analysis for pole at z = 1/2 and the general case
  - Board. Second-Order IIR Filter Analysis for all-pole case, highpass example and the general case
  - Spring 2023 Lecture notes by TA Alice Liu
- Part 2
  - Board. Review of IIR Filters
  - Demo: Time/frequency/z domain movies from DSP First, 2nd ed.
  - Demo: Matlab code for IIR filter pole-zero configurations: Left - Middle - Right (slide 6-19)
  - Filter Design Rules of Thumb and Loss of Precision due to Unfactoring
  - Handouts: "All-pass Filters" (slide 6-11) and BIBO stability (slides 6-24 and 6-25)
  - Spring 2023 Lecture notes by TA Dan Jacobellis
- Part 3
  - Board. Review of frequency response of biquads
  - Handout: "Parallel and Cascaded Realizations of IIR Filters"
  - Spring 2023 Lecture notes by TA Alice Liu
- Interactive demo for filtering audio signals
- "Tapped Delay Line on C6700 DSP"
Lecture on IIR filters in spring 2014 on Video: Part 1, Part 2, Part 3, Part 4 and Part 5.
Spring 2023 marker board notes
- Part 1
  - Video: The Voder: 1939, the world's first electronic voice synthesizer
  - Demo #1: Chromogram - MATLAB code
- Part 2
  - Biquads can give a variety of frequency responses
- Part 3
  - Pole-zero placement for a first-order IIR filter
  - In-Lecture Assignment #2: filter specifications and implementation as cascade of biquads vs. single section
Fall 2022 marker board notes
Spring 2022 marker board notes
- Part 1: First-order IIR filter: transfer function
- Part 2: Biquads and Filter design by pole-zero placement
  - All-pole biquad initial conditions for LTI and transfer function (marker board)
  - General biquad transfer function and magnitude response based on pole-zero locations (marker board)
  - Matlab code for slide 6-9: Left - Middle - Right
  - Handout O "All-pass Filters"
  - Slide 6-10 Time/frequency/z domain movies from DSP First, 2nd ed.
- Part 3: More filter design by pole-zero placement demos, stability, and filter design demos
  - Filter design by pole-zero placement demos: first-order and biquad IIR filters (marker board)
  - Bounded-Input Bounded-Output (BIBO) Stability handout and marker board notes
Fall 2021 marker board notes
Spring 2021 marker board notes
- Part 1: first-order and second-order IIR filters
- Part 2:
- Part 3: (from Spring 2014 due to winter storm cancelling courses)
  - BIBO Stability video 3:17 to 19:40, handout, and slides 6-14 and 6-15
  - FIR/IIR Filter Design Matlab Demos video 7:59 to 39:29, and slides 6-26 to 6-29
Fall 2020 marker board notes
- Part 1: IIR transfer functions and frequency responses (slides 6-3, 6-4, 6-6, and 6-8)
- Part 2: Takeaways from part 1
- Part 2: Connecting pole and zero locations to frequency selectivity (slide 6-9)
- Part 2: IIR loss of precision leads to loss of LTI properties (slide 6-12)

Last updated 03/05/25. Send comments to (Mailbox) bevans@ece.utexas.edu