Modeling Digital Signals Lab
P. 62
Copy/write a response to all the ideas in blue
P. 62
Modeling Digital Signal Lab
Part 1
62
Graph & Def.
Practice Round
Digital Process
What does Analog mean?
Table Group Discussion:
What are ANALOG signals
We live in an analog world…
With infinite possibilities
What are ANALOG SIGNALS
Analog Signal: A continuous wave that can vary in amplitude (volume) and frequency (pitch). The values of the measurements can be any number within a given range. Continuous means they are constant over time.
All real life signals are analog. For example, listening to an instrument being played live. The listener hears the waves (signals) directly. The waves are continuously being observed by your ears.
What are Digital signals
We also live in a digital world…
With finite possibilities
What is a Digital Signal?
Digital Signal: A signal that exists as a sequence of discrete bits of information.
In the case of a sound wave, this means the signal has been broken down into measurements of amplitude & frequency at only certain time intervals. It is not continuous. Digital signals are used to store and communicate information about analog signals.
Digital vs. Analog
Analog wave -
Continuous, all information is transmitted.
Digital Signal - Discrete, the wave information is coded into bits. The resolution of the signal depends on the size of the bits.
Take a moment to draw this graph in your notes! Label each line!
Digital vs. Analog
Analog Clock
Digital Clock
Discuss at your table:
How does this example demonstrate the properties of analog and digital signals?
What’s different about these two types of signals?
What are the benefits and drawbacks of each?
Digital Process - copy or draw your own
Digital communication is sent using Electromagnetic Waves (light).
Transmitter - The component in the electrical system that sends the wave based on some input (image/sound)
Receiver - Senses the electromagnetic wave when it arrives.
Image Generator - translates incoming signals received into an output message for humans to process.
Now starting the “Practice Round” Section!
Modeling Digital Signals
To investigate how digital communication compares to analog, we are going to set up a model of digital communication.
Electromagnetic Wave - Mini-flashlight (1 = 1 flash 0 = 2 flashes)
Volunteer 1 - Transmitter sends the input, a sequence of 1s and 0s
Volunteer 2 - Receiver senses the flashes and holds up # of fingers that correspond to message.
Volunteer 3 - Image generator records the sequence of 1s and 0s based on the receivers output
Whole-Class Practice
Draw a grid like this on your paper:
__ __ __ __ __ __ __ __ __
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Modeling Digital Signals
110010111
Let’s see if our team can communicate the code with 100 % accuracy!
Translating Binary into Messages
Now, lets translate that message from before into the grid:
1 1 0 0 1 0 1 1 1
1 2 3 4 5 6 7 8 9
1 | 2 | 3 |
4 | 5 | 6 |
7 | 8 | 9 |
A “1” means colored in
A “0” means leave it blank
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So, your grid should look like this!
P. 63
Modeling Digital Signals Lab
Part 2
63
You will tape the coding/recording sheet, on top of p. 64
Data Analysis
Reflection
Modeling Digital Signals
In your group of 4, try out the procedure. Take turns playing each role.
Student 1- Coder uses their Secret Code written in binary as the digital signal. Cover the rest of your secret code so Transmitter can just see the binary code.
Student 2 - Transmitter sends the input, a sequence of 1s and 0s (flashes the mini-light) based on the Coder’s binary sequence.
Student 3 - Receiver senses the flashes and holds up # of fingers that correspond to message.
Student 4 - Image generator records the sequence of 1s and 0s based on the receivers output and translates them into the grid and subsequently into a letter.
Pre-Lab
1- Write out the letters of your secret word
R
E
A
D
2- Shade the boxes to make the shape of each letter
3- Translate the image into Binary (0’s and 1’s)
This becomes your secret code during data collection!
1 1 1 1 0
1 0 0 1 0
1 1 1 1 0
1 0 1 0 0
1 0 0 1 0
1 1 1 1 0
1 1 1 1 1
1 0 0 0 0
1 0 0 0 0
1 1 1 1 1
Data Collection
1- When you are the Image Generator, fill in the first grid with the binary (1’s and 0’s)
Record ALL the binary for ALL the letters before moving to step 2
2- Translate the Binary into shaded/unshaded boxes to form the letter
3- Guess which letter it is!
1 0 0 0 0
1 1 1 1 1
1 1 1 1 0
1 0 0 0 0
1 0 0 0 0
1 0 0 0 1
1 0 0 0 1
1 0 0 0 1
1 0 0 0 1
1 1 1 1 1
1 0 0 0 1
1 1 0 0 1
1 0 1 0 1
1 0 0 1 1
0 0 0 0 1
F
U
N
Reflection (Reflect the Question!)