ECE 445S Real-Time Digital Signal Processing Laboratory - Lecture 16

Lecture by Prof. Brian L. Evans

Announcements: Cellular Basestation Design

Lecture

Lecture slides on Quadrature Amplitude Modulation (QAM) Receivers in PowerPoint format.
- Impairments due to the transmitter and receiver analog/RF front ends (see lecture slides 1-26 to 1-29)
- Lecture notes Part 1 and Part 2 by TA Jenna May
- Preview of Lab 7 on audio delay effects
  - Reverb and Delay Explained by Stella
  - Delay controls when the echoes arrive
  - Reverb consists of delays not controlled (e.g. echoes in a room)
Fall 2020 lecture notes part 1 and part 2 by Mr. Jacobellis and Prof. Evans
Lecture on QAM in spring 2014 on Video: Part 1 - Part 2 - Part 3

Supplemental Information

Fall 2025 marker board notes
- Board. Compensating for fading and additive noise
- Board. Energy detector for carrier detection
Spring 2025 marker board notes
- Board. Ways to Increase Bit Rate
- Board. Power Consumption in Data Converters
Fall 2024 marker board notes
- Data converters and their impairments
- Ideal channel time response
- Deriving update equations for adaptive LMS equalizer
Spring 2024 marker board notes
- Board: Channel Equalizer
- Board: Replacing multiplication by two with signed right shift for automatic gain control
Fall 2023 marker board notes
Fall 2022 marker board notes
- Channel capacity
- Adaptive LMS filter
Spring 2022 marker board notes
- Part 1: baseband equivalent channels and adaptive FIR equalizers
- Part 2: automatic gain control and channel equalization review
Fall 2021 marker board notes
- Part 1: QAM receiver design, IIR equalizer and adaptive FIR equalizer
- Part 2: carrier detection, symbol error rate plot, transmit power and system design tradeoffs
Spring 2021 marker board notes
- Part 1 takeaways: QAM Transmitter architectures part 1 and part 2
- Part 1 what's beyond QAM, ideal channel and adaptive LMS equalizer
- Part 2 outline, carrier detection, symbol timing recovery and gray coding and fast QAM decoding
- Part 2 upconverted PAM from Fall 2018 Midterm 2.1(b)
Spring 2020 marker board notes
- Fast algorithm for QAM decoding
- Slide 16-6: Ideal channel impulse and frequency response
- Slide 16-8: Adaptive least-mean squares (LMS) FIR filter, by adapting one coefficient and all coefficients
- Slide 16-9: carrier detection
- Slide 16-10: symbol timing/clock recovery
Fall 2019 marker board notes
- Cellular LTE SNR feedback
- Matched filter
- Equalizer design
  - Ideal Channel
  - Infinite Impulse Response (IIR) Equalizer
  - Adaptive Least Mean Squares (LMS) Finite Impulse Response (FIR) filter: one coefficient and multiple coefficients
- Symbol recovery
"An Introduction to Radio Architectures and Signal Processing", Mikko Valkama & Markku Renfors, Oct. 2011.
"Digital (Feedforward) Automatic Gain Control", Gerald Cain, DSP Creations, Dec. 8, 2016.

Last updated 04/21/26. Send comments to (Mailbox) bevans@ece.utexas.edu