Compact Tri-band Half-Mode Substrate Integrated Waveguide Loaded by Meandered Slot Line for Wireless Communications

This paper presents the utilization of a half-mode substrate integrated waveguide (HMSIW) cavity loaded with a meandered slot line (MSL) to design a miniaturized a 2nd order tri-band bandpass filter (BPF). The MSL was employed to independently control the operating passbands and to reduce the filter size. A systematic design procedure was used in this work to systematically calculate the theoretical parameters. Ansys EDT and ADS simulators were adopted to design and optimize the proposed structure and validate the achieved results. Simulation results showed that the proposed filter occupies an area of 0.041 at 4.7 GHz acquiring a compact size. Simulation results showed that the optimized structure operates with three passbands centred at 4.7 GHz, 7.28 GHz, and 9.36 GHz with insertion losses of 0.23 dB, 0.77 dB, and 1.8 dB, and the return losses of 20 dB, 19 dB, and 18 dB, respectively. The achieved findings showed that the proposed filter is compact and exhibits superior performance, which makes it well-suited for emerging multi-functionality wireless communication applications. The filter's size reductions and tri-band functionality make it a particularly desirable option for integration within miniaturized communication systems.