Microwave Filter Synthesis [From the Guest Editor's Desk]

Circuit synthesis based on lumped capacitor and inductor elements is a well-established mathematical process that dates back to the early 1930s. Over the years, it has been continuously evolving to include new ideas and other elements such as distributed transmission media of various kinds (coaxial, waveguides, microstrip, etc.). This evolution was in response to the ever-increasing demand for better performance of filters (higher frequencies, lower loss, sharp rejection, miniaturization, etc.) to meet the requirements of new electronic and communications systems such as mobile handsets, base stations, satellite transponders, and ground terminals.