Narrowband lowpass digital differentiator design

This paper describes a simple formulation for the non-iterative design of narrowband FIR linear-phase low-pass digital differentiators. The frequency response of the filters is flat around dc and have equally spaced nulls in the stopband. The design problem is formulated so as to avoid the complexity or ill conditioning of standard methods for the design of similar filters when those methods are used to design narrowband filters with long impulse responses.