IMPROVED FILTER SHARPENING

We propose a natural extension to Kaiser-Hamming filter sharpening met hods to allow for a piecewise linear desired amplitude change function (ACF), The primary advantages of the proposed ACF over piecewise cons tant ACF's is that we obtain better control of selective improvement ( or degradation) in either the passband or stopband or both, and we are not restricted to applying our methods to filters with piecewise cons tant pass and stopbands, since linear segments of slope 1, can be used to retain existing filter performance in either passband or stopband, The proposed ACF approximating polynomial (AP) is easy to compute, ma y be constrained to have simple (or integer) coefficients, and may he expressed as the AP of Kaiser and Hamming plus a correction polynomial , We also provide applications for motivation.