Department of Electrical Engineering and Computer Science 6.003: Signals and Systems-Fall 2003 PROBLEM SET 6 SOLUTIONS Issued: October 21. 2003

Problem set SolutioN Exercise for home study o&W8.35 (a) From the system diagram, we see that a(t)=a(t)cos(wet) Using the multiplication property ZGu)= o(X(u)* FT(cos wct)) FT of cos wt is two impulses with area T at +wc. Therefore, Z(w)is the spectrum

Reading Assignments Lectures #18-20 PS#9: Chapters 9 1l(through Subsection 11.3.4 )of O&W Lectures #21-22 PS#10: Chapters 10& 11(through Subsection 11. 3.4)of O&w Exercise for home study(not to be turned in, although we will provide solutions)

REMINDER: Quiz #2 will be held from 7: 30-9: 30 p. m. Thursday, November 13 in Walker Memorial. The quiz will cover materials in Chapters 4-7(through Section 7. 4)of O&w, Lectures and Recitations through October 29, Problem Sets #4-6, and that part of Problem Set 7 involving problems from Chapter 7 Reading Assignments

The lowpass filter H(u) has a cutoff frequency wc=205T rad/ sec. Thus, c(t)is r(t) where all terms with frequency above we are removed by the lowpass filter. The terms which are kept have kwol 205T rad /sec k|< 10.25, so the output, ac(t),is r(t)= To obtain n, we sample c(t) every T=5 10-3 seconds with an impulse train The sampling frequency is 400T=2 x maximum frequency in c(t). Therefore

PROBLEM SET 7 Issued: October 28. 2003 Due: November 5. 2003 REMINDER: Computer Lab 2 is also due on November 7 Reading Assignments Lectures #14-15 PS#7: Chapter 7(through Section 7. 4)and Chapter 8(through Section 8.4) of o&W Lectures #16-18 PS#8: Section 7.5 and Chapters 8 and 9(through Section 9.6)of O&W Exercise for home study(not to be turned in, although we will provide solutions)

Department of Electrical Engineering and Comput 6.003: Signals and Systems--Fall 2003 PROBLEM SET 6 Issued: October 21 2003 Due: October 29. 2003 Reading assignments Lectures #12-13& PS#6: Chapters 6&7(through Section 7. 2 )of O&w

Exercise for home study O&W4.47 tea this problem examines the Fourier transform of a continuous-time LTI system with a real, causal impulse response, h(t) (a) To prove that H(w) is completely specified by eh(u) for a real and causal h(t) lore the even part of a function, he(t)

REMINDER: Quiz 1 will be held from 7: 30 to 9: 30 p. m. Tuesday, October 14 The quiz will cover material in Chapters 1-3 of o&w Lectures and Recitations through september 26, Problem Sets 1-3 and that part of Problem Set 4 involving problems from Chapter 3 Reading assignments

MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Electrical Engineering and Computer Science 6.003: Signals and Systems-Fall 2003 PROBLEM SET 4 SOLUTION Home Study Exercise -o&e W 3.63