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Volume 13 | Issue 7 | Year 2026 | Article Id. IJEEE-V13I7P103 | DOI : https://doi.org/10.14445/23488379/IJEEE-V13I7P103

Experimental Investigation of a SRR Unit-Cell Driven Multiband Bandpass Filter using a T Shaped DGS for 5G FR1 Bands n77, n78, and n79 with Enhanced Stopband Suppression

Gauravkumar R. Asari, Priti J. Muliya

Received Revised Accepted Published
13 May 2026 13 Jun 2026 19 Jun 2026 27 Jul 2026

Citation :

Gauravkumar R. Asari, Priti J. Muliya, "Experimental Investigation of a SRR Unit-Cell Driven Multiband Bandpass Filter using a T Shaped DGS for 5G FR1 Bands n77, n78, and n79 with Enhanced Stopband Suppression," International Journal of Electrical and Electronics Engineering Volume, vol. 13, no. 7, pp. 50-69, 2026. Crossref, https://doi.org/10.14445/23488379/IJEEE-V13I7P103

Abstract

This paper presents the design, simulation, fabrication, and measurement of a novel multiband microstrip based Bandpass Filter (BPF) for 5G FR1 mid-band operation intertwining a cascaded Split Ring Resonator (SRR) unit-cell array on the top metal layer with a T-shaped Defected Ground Structure (DGS) etched into the ground covering n77 (3.3-4.2 GHz), n78 (3.3-3.8 GHz), and n79 (4.4-5.0 GHz) frequency bands. The SRR array enables regulated resonant loading and allows for multiband transmission and better skirt selectivity. The DGS, on the other hand, disturbs the return current path to generate transmission zeros and suppress the high-frequency spurious responses for maximizing the stopband attenuation. First, the retrieval of effective constitutive parameters of the proposed unit cell is performed in the goal of illustrating the metamaterial behavior. Great focus is put on permeability that demonstrates magnetic-resonance behavior at the design frequency of 4.7GHz. The entire filter is designed, developed and optimized in Ansys HFSS, fabricated on a FR-4 substrate and characterized using an Anritsu MS46122B Vector Network Analyzer (VNA). The measured return loss (S11) and insertion loss (S21) responses agree well with the simulated results and show reliable mid-band transmission within the criteria of 5G FR1 and maximum stopband suppression. The proposed SRR-DGS-based BPF provides a promising way for a compact design of multiband 5G front-end filters, low-profile and easy to fabricate.

Keywords

Split Ring Resonator (SRR), Defected Ground Structure (DGS), n77/n78/n79, HFSS, 5G FR1, VNA.

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