Maximally flat non‐recursive digital filters

A new class of polynomials with derivative constraints at both x= ± 1, is introduced. Such polynomials can be used in the design of non-recursive digital filters with maximally flat amplitude response at both ±T= 0 and ±T= 180 degrees, as well as the design of certain class of microwave networks. As compared with the already known methods1, the proposed design method provides some advantages.