Formulas for the impulse response of a digital filter with an arbitrary piecewise-linear frequency response
Manlap Chan, JAMES A. HEINEN, Russell J. Niederjohn · IEEE Transactions on Signal Processing · 1995
Simple formulas are derived for the impulse response of a digital filter with an arbitrary piecewise-linear frequency response. These are generalizations of a formula given in Oppenheim and Schafer (1989), and are useful in designing linear-phase FIR filters by the "windowing" method.>