passband ripple การใช้

• A common response function used by filter designers is the Chebyshev filter which trades steepness of the transition band for passband ripple.
• Elliptic filters are generally specified by requiring a particular value for the passband ripple, stopband ripple and the sharpness of the cutoff.
• Because of the passband ripple inherent in Chebyshev filters, the ones that have a smoother response in the passband but a more irregular response in the stopband are preferred for some applications.
• The resulting transmission function of the network has a passband ripple like the Chebyshev filter, but the ripples never reach 0dB insertion loss at any point in the passband, as they would do for the standard filter.
• Because the coefficients of digital filters are definite, they can be used to achieve much more complex and selective designs & ndash; specifically with digital filters, one can achieve a lower passband ripple, faster transition, and higher stopband attenuation than is practical with analog filters.