OFDM: Wireless Audio Transmission System

December 2022
EE-442: Wireless Device Algorithms

Objectives:

  • Use the Orthogonal Frequency Division Multiplexing (OFDM) technique, as well as DFT and phase matching, to implement a wireless data transmission system.
  • Use two speakers and a microphone to transmit audio in binary bits
  • Implement MATLAB algorithms for transmission (data packaging and pre-processing) and reception (denoising, phase correceions, decoding).
  • Write a complete test suite to evaluate design integrity (SNR vs. BER plots, performances under different fading channels, etc.)

    • Comments:

  • I worked with two graduate students at EPFL, Switzerland during my study abroad, which was 50% of the course grade. My teammates implemented most of the Block and Comb Pilot code.
  • Then, I was responsbile for testing the implementations, both experimentally and through simulations (adding Gaussian white noise, tuning the fading channels, etc.)

    • Project Deliverables:

  • A 20-page project report
  • A 15-minute presentation
  • Complete MATLAB code for the function implementations and testing. See the GitHub repo

    • Two ways of packaging the data: Block type and Comb type.

    System block diagram.

    Constellation plots of transmission results under different data packaging mechanisms.

    Optimal transmission parameters.