3/4/08
ch10 homework: 10.1,2,7,8,10.2-lab,3
read 10.1,2
quiz on thursday on DTFS discrete time fourier series

DTFT
F(OMEGA) = sum<n=-inf,inf>(f[n]e^(-jnOMEGA))
f[n] = (1/2pi)int<(2pi)>(F(OMEGA)e^(jnOMEGA)dOMEGA)
how is DTFT related to CTFT for a sampled signal?
fig1

Linear time-invariant discrete time system analysis via DTFT
fig2
dtft limitations:
	existence only guaranteed when x[n] is absolutely summable
	can only be used in asymptotically stable systems (no unstable or marginally stable systems)

limited b/c we only express signals as combinations of complex exponentials of the form e^jOMEGAn where OMEGAn is a real number

on to the Z transform to escape this issue
lets use notation F(jOMEGA) instead of F(OMEGA)
fig3