A signal is sampled with a periodic impulse train  to form a signal y(t) = x(t)p(t).(a) W...

A signal is sampled with a periodic impulse train  to form a signal y(t) = x(t)p(t).

(a) What constraint must be placed on T to avoid aliasing in the sampled signal y(t)?

---

(b) The signal x(t) is now sampled with a new periodic impulse train to form a new signal . Sketch Z(ω), the Fourier transform of z(t).