Metamaterial tri-band bandpass filter using meander-line with rectangular-stub

Abstract

In this paper, a new compact tri-band bandpass metamaterial (MTM) filter based on meander line with a rectangular stub is proposed and designed. The pseudo connections between meander line and ports generate interdigital capacitor (IDC) to provide series capacitance. Meander line with a rectangular stub realizes a virtual ground concept here. To validate the MTM property of the proposed filter structure, a dispersion diagram is plotted. The proposed filter offers measured first passbands from 1.88–4.0 GHz; second band starts from 5.4–5.9 GHz; third passband ranges from 7.1–7.4 GHz. It has insertion losses of 0.8 dB, 1.5 dB and 2.0 dB at 2.1 GHz, 5.7 GHz and 7.3 GHz centre frequencies, respectively. The designed filter will cover S band (2–4 GHz), ISM band (5.725–5.875) and fixed satellite services (7.25–7.3 GHz). Further, the designed filter shows electrical size of 0.14λ0 ×0.13λ0 at zeroth order resonance (ZOR) frequency 2.1 GHz.