Filter Design by Impulse Invariance Digital Signal Processing--IIR Digital Filter Design H(e)=之Aer:"=∑4∑(e:'y° n=0i=1 i= n=0 1-(erz1) (ex2)=0, 1-ez1 k-→0 e-1-。 ao=立+w 上游充通大￥Digital Signal Processing—— IIR Digital Filter Design Filter Design by Impulse Invariance ∑∑ ∑ ∑ ∞ = = ∞ = − = − = = 0 1 0 1 1 ( ) ( ) n N i n s T n N i i s nT n i H z Ae z A e z i i − →∞ − − − s T k s T k e z e z i i 1 1 1 1 ( ) ( ) 0, 1 =∞ = − k s T k e z i ∑ = − − = N i s T i e z A H z i 1 1 1 ( ) ∑ ∞ =−∞       = + m a a m T H s j T H s 1 2π ( ) ˆ