Discrete time IIR filter from analog filter

Chebyshev polynomial for n=3 and R = 1.1 dB In the polynomial calculated in 9.4 Hlp(s) =0.4656/(s+0.4766)(s2+0.4766s+0.977) To convert this normalized LP to desired BS, substitute s 1.218 s / (s2+ 0.2180). Use BZT in the so obtained polynomial in s.

1. Butterworth filter. Number of poles of LP filter  = log10 {(10-Gs/10 –1)/ (10-Gp/10 –1)} / 2log10 (s/p) = log10{(102-1)/(100.3-1)/2 log10(2.856) = 2.199  3 (for better transition characteristic). The normalized TF = 1/ (s+1)(s2+s+1) = 1/ 1+2s+2s2 +s3 Transform normalized LP to required BS by s 1.218 s / (s2+ 0.2180) USE BZT on the HBS(s).