Miniaturized open-ended dual-band band-pass filter with series stepped capacitance and shunt meandered line inductance for microwave frequency applications

Abstract

AbstractIn this paper, a miniaturized open-ended dual-band band-pass filter with stepped series capacitance and shunt meandered line inductance for microwave frequency applications has been designed and discussed. In order to offer ease of fabrication and uniplanar configuration, coplanar waveguide feeding arrangement has been used. Zeroth order resonance, a special phenomenon of composite right/left handed transmission line has been utilized to miniaturize the filter size. The designed filter structure offers miniaturization with overall footprint size of 0.26λg × 0.19λg, where λg is the guided wavelength at the center frequency of 1.46 GHz. It offers 58.90% (1.03–1.89 GHz) and 25.93% (2.55–3.31 GHz) measured −3 dB fractional bandwidth with respect to the center frequencies of 1.46 and 2.93 GHz, respectively. Dispersion plot has been utilized to discuss the metamaterial properties for the proposed dual-band band-pass filter. In addition to above, the proposed filter structure presents almost flat group delay curve within both passbands. The proposed filter structure can be suitably utilized for distinct wireless applications, for example global navigation satellite system (1.559–1.610 GHz), GSM1800 (1.7–1.8 GHz), Wi-MAX (2.5–2.7 GHz), and naval radar and air traffic control (2.7–2.9 GHz).