All About Phase

While students generally demonstrate an intuitive understanding of transfer function magnitude terms such as low pass and band pass, they are often bewildered by the concepts of phase and its relationship to delay. We find that although students can easily learn the formulas and demonstrate the computer commands necessary to produce phase plots, they frequently cannot explain what the plot means, or how they might determine whether or not their implementation of a particular filter matches the theoretical phase response. To address this gap in student learning, we are experimenting with a set of lecture notes and corresponding hands-on laboratory experiments specifically dealing with system phase and delay relationships. Our preliminary results indicate that this special treatment of phase is both effective and efficient for increasing student confidence and ability in handling phase-related engineering questions.