A continuoustime signal is given by yt 72cos1200 pi t pi2

A continuous-time signal is given by y(t) = 7.2cos(1200 pi t - pi/2). What is the frequency in hertz of y(t)? What is the period of y(t)? Plot one period of y(t) versus t. If y(t) is to be represented by its sample values, what is the minimum frequency at which it should be sampled? What is the sampling period for the frequency found in part (d.)? If y(t) is sampled with a period of T = 0.001sec, find the expression for the resulting sequence y[n]. What is the digital frequency, omega, of y[n] for the value of T given in part (f.)?

Solution

a) frequency = w/2*pi

= 600

b) period = 2*pi/1200*pi

= 1/600

c) plot represents cosine

d) minimum frequency = 2f

= 1200

e) sampling period = //2f

= 1/1200