A signal Mt) is multiplied by the rectangular pulse train c(t) shown in Figure P8.10....

A signal Mt) is multiplied by the rectangular pulse train c(t) shown in Figure P8.10.

(a) What constramt should be placed on X(jω) to ensure that x(t) can be recovered from the product x(t)c(t) by using an ideal lowpass filter?

(b) Specify the cutoff frequency and the passband gain A of the ideal lowpass filter needed to recover x(t) from x(t)c(t). [Assume that X(jω) satisfies the constraint determined in part (a).]