A self‐packaged multilayer all‐metal integrated suspended slotline dual‐band filter

Abstract This paper introduces a novel implementation technology for realizing dual‐band bandpass filtering responses using high‐ slotline resonators with self‐packaged multilayer configuration. The concept of a 3D slotline is introduced, which utilizes the innovative metal‐integrated suspended line (MISL) technology. This technology utilizes an all‐metal structure, effectively eliminating dielectric loss. Furthermore, the implementation of an encapsulated structure significantly reduces radiation loss in the slotlines. Thus, the factors are greatly improved. Based on MISL, a dual‐band bandpass filter with wideband responses and multiple transmission zeros was designed, fabricated, and tested based on 3D cascaded‐mode half‐wavelength resonators. The test results demonstrated a high level of consistency with the simulation results, confirming the high‐ characteristics of the proposed 3D slotlines.