High-Power Ku-Band Narrowband Subwavelength Locally Resonant Metamaterial Filter for Space Applications

This paper presents a high-power Ku-band subwavelength bandpass filter based on a volumetric locally resonant metamaterial (LRM) waveguide topology, targeting compact narrowband filters for space applications. The structure consists of a rectangular waveguide loaded with a small number of periodically arranged metallic pins operating below the cutoff frequency of the host guide. Hybridization between the evanescent TE10 mode and the local resonances creates a slow, subwavelength guided mode and a hybridization bandgap (HBG), which are exploited to synthesize a three-pole Ku-band filter with sharp selectivity and reduced footprint. The multipactor (MP) behavior is assessed using full-wave simulations combined with SPARK3D analysis and ECSS-compliant TEEY models (gold material) showing a MP threshold of 19 kW, well above typical requirements for satellite payloads and substantially higher than a reference Ku-band filter from the prior art.