cheb2ord
Chebyshev Type II filter order
Description
Examples
Input Arguments
Output Arguments
Algorithms
cheb2ord
uses the Chebyshev lowpass filter order prediction formula described in[1]. The function performs its calculations in the analog domain for both analog and digital cases. For the digital case, it converts the frequency parameters to thes-domain before the order and natural frequency estimation process, and then converts them back to thez-domain.
cheb2ord
initially develops a lowpass filter prototype by transforming the stopband frequencies of the desired filter to 1 rad/s (for low- and highpass filters) and to -1 and 1 rad/s (for bandpass and bandstop filters). It then computes the minimum order and natural frequency required for a lowpass filter to match the stopband specification exactly when using the values in thecheby2
function.
References
[1] Rabiner, Lawrence R., and Bernard Gold.Theory and Application of Digital Signal Processing.Englewood Cliffs, NJ: Prentice-Hall, 1975.