Numerical Results for Group Delay of Minimum Phase Bandpass Filters

Using the Hilbert transform theory, an expression for the group delay of a minimum-phase bandpass filter is derived. Group delay as a function of amplitude response characteristics (shape factor, bandwidth, and ultimate attenuation) is numerically determined for high-quality filters of the MIL-STD-188C and DCA types. The results are useful in estimating the performance of data transmission systems over unequalized (e.g., voice) links and the difficulty of constructing phase equalizing networks.