Question $1$:

a$.$ If the message $m(t)($shown if Figure $1)$ is to be transmitted using a wirelss communication system. Sketch the AM modulated signal $($label the message$)$ and the FM modulated signal.

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b$.$ Define "ailisasing" and state two techniques that can be used to avoid it$.$

c$.$ Find the Nyquist rate and Nyquist interval of the following signals

i$.,x(t)=sinc(400t)$

ii$.,y(t)=sin{c}^2(2\mathrm{.}5t)$

iii. $,z(t)=cos(2000t)+sin(6000t)$

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