Question

A student (A) who hasn't studied the sampling theorem properly, sampled the following signal at 200 rad/sec. The student then provided the discrete time signal to another student (B - who knows the sampling theorem and signal reconstruction very well) telling them that the signal was sampled at 200 rad/sec. (t) 3cos(500Tt) +2cos(100mt) a) Derive the discrete time signal that student A created in its most simplified form. b) Explain how student B can try to recover a continuous signal from the discrete time signal that student A provided. c) Will student B manage to recover the original signal? If not then explain how the recovered signal will look like. (What are the frequencies that student B will see in the recovered signal and how do those frequencies compare to the original signal). Note: just describe what happens to the frequencies -do not derive the recovered signal.

Answer 1

s 500 n 1000 For discrele Signol. t rpla.ced by nTs LDo u 2 15 70 2oo63 66 100η . SooTT ve Il get frequercia ofb 563 6 36.4η 163-61 436. 4,0 5c36

Gcneral afler Scampli ) T The cant recovc the origTnal Simal because we used hore Generally for Samplirg u Alias Then obscowed frequenaies coiu be 2 T