Lab Name Properties of waves, using experiment allowing the visualization of Digital AM and FM wave signals.
Subject Area Science
Grade 8
Topic Waves
Experiment Title Visualization of digital AM and FM wave signals showing the frequency and amplitude.
Hardware Linux machines (ex laptop, raspberry pi) and 2 Software Defined Radios (ADALM Pluto).
Software GNU Radio and COSMOS toolkit framework.
Number of Sessions to teach the topic 1 - 2 sessions
Educational standards to be addressed
  • MS-PS4-3
    Integrate qualitative scientific and technical information to support the claim that digitized signals are a more reliable way to encode and transmit information than analog signals.
COSMOS concepts to be used for the lab Wireless signals, visualization of digital AM and FM wave signals on the computer screen, relationship between the two, frequency and amplitude.
K12 Educational Goals (How the educational goals are achieved through teaching using the experiment, how the topic is connected to the COSMOS concepts used) Teaching the properties of waves by visualizing digital AM and FM wave signals on the computer screen and observing the difference between the two, frequency and amplitude.
Short Description and Walk-through of the experiment
  1. Teacher will use a short slide-show to introduce & explain the topic of waves, the different types of waves & the properties of waves.
  2. Materials & equipment are set up on student's desks.
  3. Activity:
    1. Students will observe (visualize) and listen to the digital video being played using amplitude modulation AM and record their observations.
    2. Students will observe (visualize) the digital video being played using frequency modulation FM and record their observations.
    3. Students will then compare & contrast the two.
Testbed mapping of the experiment We can configure a particular node to transmit a digital AM signal and another to transmit a digital FM signal and display the information showing the wave form and spectrogram. So, we perform the experiment using nodes on the testbed and we can visualize the wave signals on the computer screen. From this visualization we can observe the relationship between the two.

Experiment Execution

Select a modulation scheme (AM or FM) and the appropriate function of the Node (Transmitter or Receiver), and press START to begin the experiment. In order to terminate the experiment press STOP.
AM Modulation FM Modulation

Experiment Material

NGSS Lesson Plan
Worksheet
Presentation

© 2018 COSMOS Project. Created by Richard Foster, Parkside Preparatory Academy MS2 Brooklyn, New York