Periodic Signals,
What does periodic mean? Repeating, right? Yes, but what about
the phase and applications of periodic analysis. Consider
a signal : Whenever a text says “consider a signal” the author typically wants you to picture the signal in your head or actually plot it. Reading math is pointless if you aren't visualizing the functions response.
Mmmkay, don’t just consider the signal, put the signal into Excel (or the Open Office free version) by: - Make a column(A,B,C…) with numbers, representing phase in degrees, from 0-360 (2π radians)
a. Start by filling out the first 3 rows: 0,1,2 b. Highlight the 3 rows and drag down to fill in values to 360 2. Convert the values to radians by multiplying by π/180 (The astute reader knows that there is a radians() command in excel that does the same thing. You should always know (or at least try to) what a function/command is doing.)a. Type into the first column of row B: =(pi()/180)* i. Left arrow to grab column A, Row 1 ii. Hit Enter to finish 3) Now in Column C a. Type =cos( i. Left arrow to grab column B, Row 1 ii. Hit Enter to finish b. Highlight Columns A,B and C and drag fill down to row 361 You should have 3 populated columns 4) Select column C by clicking on “C” a. Insert a line graph by selecting the “insert tab” then selecting the line graph If everything went right you should get a Cosine wave from 0degrees to 360 degrees
Now, the Cosine signal doesn’t really look like a traditional wave response… How can we improve this? Periodic Examples |

Math Applied >