ELEC 320, Fall 1998
Prof. Rich Kozick

Homework 12

Date Assigned: Friday, October 2, 1998
Date Due: Monday, October 5, 1998

1. Quiz 2: We will have Quiz 2 on Wednesday, October 7. The topics for the quiz include classifying systems (linear and time-invariant), impulse response, and convolution for discrete-time and continuous-time systems. For practice with computing the convolution operation, I would suggest that you work on Homework 11, this homework assignment, and Lab 3.

2. For Lab 3, you can omit item 8 from the lab report. We will discuss this item in class on Friday, October 9.

3. We will not have lab on Thursday, October 8 in order to keep the Tuesday and Thursday sections from getting too far apart. (The Tuesday lab section will not meet on November 24 prior to Thanksgiving break.)

4. Listed below are some extra problems to give you more practice with discrete time systems. These do not have to be handed in, but I will answer questions about these problems in class on Monday.
• Problem 3.2 in the text for practice with impulse response.
• Problem 3.5, parts (a) and (b) for convolution. Remember that you can check your result with the MATLAB command conv.

5. A Java applet that graphically illustrates continuous-time convolution is available at
http://www2.ece.jhu.edu/wjr/
with the title "Joy of Convolution". I think that this exercise helps you to visualize the convolution operation, and I suggest that you should check it out. (Nothing needs to be handed in for this part.)

6. Please perform the following continuous-time convolution operations:
Problem 3.15 (all parts). For case (c), the integral needs to be evaluated explicitly. I suggest that you draw pictures in order to get the proper limits on the integral. Do your best on these problems, and we will review the solutions on Monday.

7. For more practice, try Problem 3.19 (hint for part b: use linearity and time-invariance with your answer from part a). However, this does not need to be handed in.

Thank you.