Transmission factors of microwave filters with prescribed attenuation and group delay

Synthesis procedure is presented for determining transmission factors of a broad class of microwave filters using commensurate line lengths which satisfy prescribed attenuation and group delay characteristics. This technique, which lends itself to automatic programming, derives its origin from a previously described method of increasing selectivity in linear phase microwave filters and depends on the introduction of a second frequency transformation which is well known in the theory of lumped element filters. The organization of the computer program is discussed and a few numerical examples are worked out to facilitate the comparison of the results with those previously obtained.