y(m)=∑k)x(Mm-k)ymn)=∑h(Mm-k(k) k: y份小=/)n=0±M+2M 0 其他 r(n)=y().∑6(n-kM) k=-∞ wIn j2TI n/M e <n<0( )  ( ) ( )  =− = − k y m h k x Mm k ( )  ( ) ( )  =− = − k y m h Mm k x k ( ) ( )     =     = , 其他 w n , n , M, M w n ( ) ( ) ( ) ( )  −          =  =  −   − =  =− e n M w n w n w n n k M M l j l n M k , 1 1 0 2 