Group delay sensitivityߞits estimation and application

The output of a filter network gets distorted due to changes in the level of the group delay of its transfer function and group delay sensitivity could, accordingly, serve as an index of such distortions. A formulation relating the group delay sensitivity to polynomialcoefficient sensitivity, which enables a quick evaluation of the former, is proposed and its use as a selection criterion is illustrated with the active RC network synthesis of a second-order low-pass Bessel filter.