Citation :

Gauravkumar R. Asari, Priti J. Muliya, Rina N. Bhatt, Ami B. Gandhi, "Metamaterial Inspired Open Ended Coupled Line Bandpass Filter using Twin Split Ring Resonators for X-Band RADAR and Satellite Communication," International Journal of Engineering Trends and Technology (IJETT), vol. 74, no. 6, pp. 421-439, 2026. Crossref, https://doi.org/10.14445/22315381/IJETT-V74I6P128

Abstract

The research paper shows the development and optimization together with performance testing of a 9.7 GHz Bandpass Filter (BPF) which takes its design elements from metamaterials through the application of open-ended coupled lines that work with twin Split-Ring Resonators (SRRs). The research first conducts a complete structural and electromagnetic investigation of the SRR to study how different ring gap, ring width, and inter-ring distance dimensions affect the resonant behavior of the structure. The Nicolson Ross Weir (NRW) method uses full-wave S-parameter simulations to extract the effective permittivity and permeability of the resonator, which shows negative permittivity and magnetic resonance near the operating frequency. The filter design uses an RT/Duroid 4003 substrate (εr = 3.55, h = 0.85 mm) and places twin SRRs at specific locations, which boost electromagnetic coupling within the coupled-line section. The research demonstrates that SRR loading enhances electric-field confinement through its ability to create new paths for capacitive inductive interaction, while it also improves near-field coupling. The filter shows 1.26 GHz bandwidth improvement together with 0.34 dB insertion loss reduction and 37.91 dB out-of-band rejection performance when compared to the filter design, which does not include SRRs. The inclusion of SRRs also sharpens selectivity by generating transmission zeros near the passband edges. The research results demonstrate better performance than existing studies in size, passband attenuation, reflection loss, bandwidth, rejection, and selectivity metrics. The SRR-loaded BPF achieves compact design with effective out-of-band suppression and minimal loss, which makes it suitable for RADAR front ends, satellite transceivers, and broadband microwave communication systems.

Keywords

Bandpass Filter, Split Ring Resonator, S Parameters, HFSS.

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