2)X,(ko, no )Wo=X,(ko, no) 3)(,k)的4点DFT (,0)1「? W4 WA WX(,)ne X(4,1)ww4w2w‖x(1)形 X(2)|w0W2WW‖x(,2)B X(4,3)LWw?w2W⊥x(k,3)」 1X(k20)形 1111 X1(k21)W6 X,(k, 2W 1(k,3)W78    0 0 ' 1 0 0 1 0 0 2) , , n k X N k n W  X k n 3) n0 ,k1 的4点 DFT                 0 0 0 0 0 0 0 0 2 0 4 4 4 4 1 0 16 0 1 2 3 2 0 4 4 4 4 1 0 16 0 2 0 2 2 2 0 4 4 4 4 1 0 16 0 3 2 1 3 2 0 4 4 4 4 1 0 16 ,0 ,0 ,1 ,1 ,2 ,2 ,3 ,3 k k k X k W W W W X k W X k W W W W X k W X k W W W W X k W X k W W W W X k W                                        0 0 0 0 1 0 16 1 0 16 2 1 0 16 3 1 0 16 1 1 1 1 ,0 1 1 ,1 1 1 1 1 ,2 1 1 ,3 k k k X k W j j X k W X k W j j X k W                      