The World's Most Interesting FIR Filter Equation: Why FIR Filters Can Be Linear Phase

Rick Lyons
6 comments

This article discusses a little-known filter characteristic that enables real- and complex-coefficient tapped-delay line FIR filters to exhibit linear phase behavior. That is, this article answers the question: What is the constraint on real- and complex-valued FIR filters that guarantee linear phase behavior in the frequency domain?