Prof. Kelley's Home Page

Research Topics

• Research Overview
• FDTD Method
• IPR Antennas
• Pedagogy
• Phased Arrays
• Reactively Controlled Arrays
• Yagi-Uda Arrays
• Paper Count

Pedagogy

Every undergraduate student in electrical engineering must take a course in the fundamentals of electromagnetics. This is a very challenging course for most students, because it demands competence in the use of vector calculus and complex variables. I am continually trying to find ways to make this sometimes abstract subject matter easier to understand and to point out the practical applications of the material. This effort included collaboration in a study of the state of electromagnetics education in North American universities in the mid-2000s.

In my senior elective course, Wireless System Design (ECEG 497), it has been a challenge to help students understand the application and calculation of S-parameters (short for scattering parameters), a widely used method of characterizing the system-level performance of RF (radio frequency) circuits at VHF, UHF, microwave, and millimeter-wave frequencies. The frequency response of filters, the gain and interfacing properties of amplifiers, and mutual coupling in phased array antennas are almost universally expressed in terms of S-parameters. I have developed a simplified calculation method for students new to the topic. The method also promises to provide a way to help validate the accuracy of computer-based electromagnetic simulation models.

But I don't just teach electromagnetic theory. All professors at Bucknell teach a variety of courses, and I frequently teach courses in electronics, circuit theory, and advanced mathematical methods. These topics pose challenges to students as well, and my colleagues and I are always working on ways to improve student engagement and comprehension. My efforts in this area have included emphasizing the importance of good circuit layout at high frequencies and ensuring that students emerge from laboratory experiences with good test and measurement skills.

Journal Paper

• David F. Kelley, "The Good, the Bad, and the Ugly: Demonstrating Basic Circuit Layout and Measurement Concepts," IEEE Antennas and Propagation Magazine, vol. 49, no. 6, December 2007, pp. 153-156.

Conference Papers

• David F. Kelley, "Calculating Power Wave S-Parameters Using Only Port Voltages or Currents," 2023 IEEE International Symposium on Antennas and Propagation, Portland, OR, July 2023.
• David F. Kelley, "Calculating S-Parameters Using Only Port Voltages," 2022 IEEE International Symposium on Antennas and Propagation, Denver, CO, July 10–15, 2022.
• Peter Mark Jansson and David Kelley, "Increasing Hands-On Laboratory Equipment Experience Via Rotation of Notebook Recording Duties," 119th ASEE Annual Conference & Exposition, San Antonio, TX, June 10–13, 2012.
• Sembiam Rengarajan, David Kelley, Cynthia Furse, and Lotfollah Shafai, "Electromagnetics Education in North America," 28th General Assembly of International Union of Radio Science (URSI), New Delhi, India, October 2005.