7.1 Linear-phase FIR transfer function Consider first an Fir filter with a symmetric Impulse response: h(n)=h(N-1-n Its transfer function can be written as H(2)=∑h(m)z=∑h(N-1-m)z By making a change of variable m=N-1 n we can write H(z)=>h(m)z-w--m)=2-(->h(m)zm 期一0 (N-1) H(x-)7.1 Linear-phase FIR transfer function