Experimental Validation of a Novel Dual-Slot SIW Bandpass Filter for 5G Ka-Band Applications

Abstract

This study details the design, optimization, and experimental validation of an innovative dual slot Substrate Integrated Waveguide (SIW) bandpass filter intended for 5G Ka-band applications. The proposed filter is implemented on a cost-effective Rogers RO5880substrate and exhibits a second-order quasi elliptic response achieved by etching a novel transverse dual-slot topology within the SIW cavity. The filter was fabricated using standard PCB procedures. The measured results show strong agreement with simulations, confirming the robustness of the design. The small device measures14.15×27.86 mm² and functions effectively inside the 27-29 GHz range, attaining a fractional bandwidth of 8.81%,a return loss of -42 dB, and an insertion loss of -3.16 dB. These results demonstrate that the proposed dual-slot SIW filter provides a highly selective, miniaturized, and low-cost solution, making it a promising candidate for integration in next-generation 5G millimeter-wave front-end systems.