Download Signal & Noise - Institute for Systems Biology

Observing Beyond our Senses:
Inquiry Drives Technology
Lesson 4 – Signal & Noise
Teacher Helping a Student
What’s the Signal?
What’s the Noise?
Commodities Traders in Chicago
Signal?
Is sound the only noise?
Urban Astronomer Viewing the Stars
Signal?
Noise?
Operational Definitions
• What is signal?
• What is noise?
How are these examples of noise
similar to the previous examples?
How are they different?
Webcam
Analog TV
Can Noise Exist
in the Absence
of Signal?
How can we refine our
operational definition of noise?
Signal?
Noise?
Zoom in on a
motionless Cart . . .
How does this
noise compare to
the last example?
How do calculations
to obtain velocity
affect the noise?
Thermal Noise in Electronics
Random variations in current or voltage caused by the
random movement of the electrons carrying the
current as they are jolted around by thermal energy.
Intended Signal
“Noisy” Electronic Device