数 理 着考处 式中 X(k)=X(e)=∑x(m n=-00 ∑∑x(n+ We v(ntrwk2r r=-0n=0 ∑[∑x(n+rN)k r=-00 ∑[x(n)*(n)emk n=0 ∑(n)W (6,2.10)0 0 0 1 2 ( ) 0 1 2 0 1 0 1 0 () ( ) ( ) ( ) [ ( )] [ ( ) ( )] ( ) (6.2.10) jk jmk m N j n rN k N r n N jnk N n r N jnk N n N nk N n X k X e xme x n rN e x n rN e xn n e x nW ω ω π π ω δ +∞ − =−∞ +∞ − − + =−∞ = − +∞ − = =−∞ − − = − = = = = + = + = ∗ = ∑ ∑ ∑ ∑ ∑ ∑ ∑   式中