A Novel Resonant Window Having Dual-Behavior Resonance for Pseudo-Elliptic Waveguide Filter

This paper presents a high-performance waveguide filter constructed by novel metallic resonant windows, which have a resonant characteristic with two attenuation poles on both sides of a passband, that is, a dual-behavior resonance. Such resonant windows make it possible to produce multiple attenuation poles without any additional coupling structures, thereby realizing a compact and light-weight filter. As a design example, a 3-pole Chebyshev waveguide filter with six attenuation poles at X band was shown. The validity of the filter is proven by the comparison of the frequency characteristics between the calculated and the measured results