Fourier Series / Fourier Transform Question

SpeedBird

Hello there,

Im sure someone on this forum must know how to go about this.
It is part of an exam question.

Firstly I must draw a sketch of this pulse:

v=0 when |t| > a
v=V0( 1 + t/a ) when -a < t <= 0
v=V0( 1 - t/a ) when 0 < t < a

v represents amplitude, V0 represents peak amplitude, t represents
time and 'a' is a constatnt.

i can draw the pulse ok, it is just a triangular pulse that goes from
0 at t = +a and -a to V0 when t = 0.

The bit I am unsure about is obtaining and sketching the frequency
spectrum of this pulse. Any ideas?

Thanks,

Nik

Hurkyl

Isn't there an ethics problem with getting assistance with an exam question?

SpeedBird

maybe if i was in the exam at the time.
it's a question from last years signal analysis exam.
thanks anyway!

SpeedBird

does anyone have any ideas?

Hurkyl

Well, have you computed the fourier transform?

SpeedBird

i havnt computed the FT. the integration is huge and i get stuck pretty quickly. do you think getting the Freq spectrum could mean getting [tex]a_k[/tex] and [tex]b_k[/tex] coefficients for the fourier series and plotting their magnitudes against [tex]k[/tex]?

Hurkyl

I'm having difficulty seeing the trouble -- the integral should be something straight out of a calc II class, whether you use sines & cosines as your basis, or you use complex exponentials.