In this paper, a compact triple-band bandpass filter using metamaterial (MTM) inspired structure with controllable transmission zero (TZ) position has been proposed. The gap between feed lines develops electrical coupling and provides series capacitance. An open loop rectangular ring resonator with meander line and rectangular stub develops electric and magnetic couplings separately. Defected ground structure (DGS) provides proper impedance matching and increases the passband. In order to validate metamaterial (MTM) behaviour of designed filter dispersion diagram has been plotted. The position of transmission zero can be controlled by electric and magnetic coupling. The measured operating frequency ranges of three passbands are 1.85-2.15 GHz, 3.55-3.73 GHz and 3.85-4.0 GHz with the 3 dB fractional bandwidth of 15.63, 4.94 and 3.82 percent, respectively. It has minimum insertion loss of 0.7 dB, 0.5 dB and 0.5 dB at the 1st, 2nd, and 3rd passbands, respectively. The electrical size of the proposed filter is 0.16λg×0.15λg, where λg is the guided wavelength at zeroth order resonance (ZOR) frequency of 1.92 GHz.
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