written 6.5 years ago by | • modified 5.5 years ago |
i)
x(n)=1,0<n<3
x(n)=0,4<n<7
ii)
x1(n)=1,n=0
x1(n)=0,1<n<4
x1(n)=1,5<n<7
x2(n)=0,0<n<1
x2(n)=1,2<n<5
x2(n)=1,6<n<7
written 6.5 years ago by | • modified 5.5 years ago |
i)
x(n)=1,0<n<3
x(n)=0,4<n<7
ii)
x1(n)=1,n=0
x1(n)=0,1<n<4
x1(n)=1,5<n<7
x2(n)=0,0<n<1
x2(n)=1,2<n<5
x2(n)=1,6<n<7
written 6.5 years ago by |
x(n)={1,1,1,1,0,0,0,0}
DFT by DIF-FFT
Output of stage-1
S1(0)=x(0)+x(4)=1+0=1
S1(1)=x(1)+x(5)=1+0=1
S1(2)=x(2)+x(6)=1+0=1
S1(3)=x(3)+x(7)=1+0=1
S1(4)=[x(0)−x(4)]W08=(1−0)(1)=1
S1(5)=[x(1)−x(5)]W18=(1−0)(0.707−j0.707)
S1(6)=[x(2)−x(6)]W28=(1−0)(−j)=−j
S1(7)=[x(3)−x(7)W38=(1−0)(−0.707−j0.707)
Output of stage-2
S2(0)=S1(0)+S1(2)=1+1=2
S2(1)=S1(1)+S1(3)=1+1=2
S2(2)=S1(0)+S1(2)]W08=(1−1)W08=0
S2(3)=S1(1)+S1(3)]W28=(1−1)W28=0=0
$S_2 (4)=S_1 (4)+S_1 …