1. Simple Waveform
Polarity and Interaction

2. a simple sine wave
the signal is bi-polar
(it oscillates between positive and negative values)

3. Polarity
• the property of being polar (having positive
and negative values)
• the relationship between the positive and
negative portions of two waves

4. same polarity
• these two signals have the
same polarity
• when one is positive, the
other is also positive
• when one is negative, the
other is also negative

5. different signals - same polarity
• these two signals are
different, but they have
the same polarity
• when one is positive, the
other is also positive
• when one is negative, the
other is also negative

6. opposite polarity
• these two signals have
opposite polarity
• when one is positive, the
other is negative
• when one is negative, the
other is positive

7. What happens when two
identical signals are combined
(added together)?

8. same polarity addition
• these two signals have the
same polarity
• when they are combined
(added together)...

9. the amplitude doubles
=

10. What happens when two
signals with opposite polarity
are combined (added
together)?

11. opposite polarity addition
• these two signals have
opposite polarity
• when they are combined
(added together)...

12. the waveforms
cancel each other out
=