A New Compact Bandpass Filter for 5G MillimeterWave Communications

This research presents an innovative compact filter specifically designed for millimeter-wave communications in the context of 5 G technology. The filter is characterized by dimensions measuring $3.6 \mathrm{~mm} \times 1.8 \mathrm{~mm} \times 0.8 \mathrm{~mm}$ and utilizes FR4 as the substrate material. The analysis conducted through HFSS (High-Frequency Structure Simulator) simulation facilitated a thorough examination of the filter’s efficiency. The suggested bandpass filter exhibits a significant bandwidth spanning from 36.2 GHz to 39.6 GHz, with its central frequency set at 37.6 GHz. It showcases impressive specifications, including a return loss below -32.15 dB, an insertion loss of -1.3 dB, a fractional bandwidth (FBW) of $\mathbf{9} \%$, and a quality factor of 11. Particularly, the Voltage Standing Wave Ratio (VSWR) stands at 1 at the resonance frequency, with the group delay consistently staying under 91 picoseconds throughout the designated frequency spectrum. Importantly, the operational bandwidth of the filter aligns seamlessly with the frequency regulations of various countries, encompassing Australia (39 GHz), the United States (37-37.6 GHz), and Canada (37 - 37.6 GHz).