Question

Only Question 5

k 00 (c) Find E in (b) if x(n) = sin(2n)/(7n) and h(n) = sin(n)/(n) 5. C/D converters sample analog signals x.1(t) and xc2(t) at a sampling rate 1/T to produce x(n) and x2(n) respectively. The Fourier transforms of x1(t) and x2(t) have cut-off frequencies Qj and Q2 respectively (a) Assume that x,(n) is filtered by an ideal lowpass digital filter having a cut-off frequency of T/5 radians, producing an output y(n). y(n) is passed through a D/C converter with a sampling rate 1/T to produce the output y,(t). For what range of sampling periods T is y,(t) a lowpass filtered, unaliased version of Хa (t) ? (b) Assume that there is no digital filter, but that y(n) is formed as y(n)= X(n)X2(n) before going through the D/C converter to produce the output y.lt). For what sampling periods T is y.(t) = [xc1(t)Xc2(t)]° ? 6. For |wl TT, assume that

Answer 1

5.Sol:

  
ven , . * ,() . Sq o Both Xc, (f) & Xz (f) are sampled at 'It rate . , хъ,() . ДИА r-t, li t e, ? - 1) -, -), -1-8) – 2, o 3-, Хр,(8) «V1 r - л, Е , v .

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b) [XGCH), Koulet! Jó c 6(eli +12) 7 ► febrer 61032 +) u go there is an Digital Digital filter It should be E z a[6(84+12)] Te veo then