**Unformatted text preview: **W ELEC 2120 Spring 2013 Exam 1 Name: ‘ 1. The Fourier Transform (FT) of x(t) is shown below (X(w)}. Accurately sketch only —— the FT of the
following functions in the space provided
ll 3) Y1(t) = x(t)exp(jmt)
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reconstructed after filtering (DD = — [O rad/Sec, Kim £31 an 2. Find the Fourier Transform of the following signals if X(w) is shown below: (place answers in
spaces provided for full credit and show work) as Mt) = tzxm X09): b. y2(t)= x(t)*x(t) (convolution) 1
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I 2%,. 7‘0 ELEC 2120 Test 2 Spring 2013 Name: 1, A continuous time signal x(t) has the Laplace transform X(s).
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() s3+53+7 Determine the Laplace— transform for the following signals and place answers in box. I a. v(t)=x(3t—4)u(3t—4) VlSl= Sqﬁqsgagsqj , 73544
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l \/ 2. Determine H(s) and the time domain form of the hlt) for the circuit shown below using Laplace
Transforms. Show all work and place answers in box. SKA) Determine the transfer function H(s) 9—" 5 b) Determine h(t) ifA = 4 and B = 1/2 §Q\:“‘XCS) " Agm “Q;
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5' m M r l = Llegé‘um a; :, M A \. 3. For the discrete—time system shown below determine the following: x[n]
A
’3 3. Determine H(z) = Z’A'
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l? A: 0) MN“ 54' lies Uh (My? Lil/“CL; ' - - - N t > o
if c. Determine the discrete time pulse response: h[n] : ' — A“ uCn] 8
5+4. \/4. Suppose a system has the following transfer function: H(s) 2 Compute the system response to the following signals: S/Va. x(t) : u(t) m = _(.Z_‘Z€_ﬂ%).‘4[€}__ X6): E
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