解:(1)根据题意可知 2(O)=(n=4) 则H2(k)=∑1(m-4)形R(n) 0 =∑h(W8W=W“∑h( H,(kW 4k 由上式可以看出 H2(k)=H1(k) 2(k)=a(k)- 8 4k=B2(k)-k解：（1）根据题意可知 2 1 (( )) (( )) 8 8 h n h n = − 4 则 ( ) 4 3 4 1 8 8 4 i n ki k i h i W W = − = − =  ( ) (( )) ( ) 7 2 1 8 8 8 0 4 nk n H k h n W R n = = −  ( ) 4 1 8 k = H k W 由上式可以看出 H k H k 2 1 ( ) = ( ) 2 1 1 ( ) ( ) ( ) 2 4 8 k k k k k      = −  = − ( ) 7 4 8 1 8 0 k ki i W h i W = = 