Design of microwave filters

A survey of the major techniques used in the design of microwave filters is presented in this paper. It is shown that the basis for much fundamental microwave filter theory lies in the realm of lumped-element filters, which indeed are actually used directly for many applications at microwave frequencies as high as 18 GHz. Many types of microwave filters are discussed with the object of pointing out the most useful references, especially for a newcomer to the field. Index Terms--Bandpass, cavity, ceramic, coaxial, combline, diplexers, evanescent mode, filters, hairpin line, high-pass, high temperature, interdigital, low-pass, lumped element, microstrip, microwave, multiplexers, parallel coupled line, planar, stripline, superconducting, waveguide.