A Compact Metamaterial-Based Open-Ended CPW Band-Pass Filter for Wireless Applications

Abstract

This article suggests an open-ended coplanar waveguide band-pass filter using stepped-impedance resonators (SIR) and complementary split-ring resonators (CSRR) that operates at a wider bandwidth with higher band selectivity at 4G-LTE applications. The filter described here is collimated to work in the frequency range of 2.23-4.2 GHz. SIR is used to provide improved selectivity at 2.6 GHz and 3.5 GHz with a return loss of − 30 dB and an insertion loss of − 0.2 dB. Similarly, including CSRR in the design aided in attaining broader bandwidth by ensuring a low ripple value across the bandwidth. The fractional bandwidth of 61.3 percent and a 2 GHz broad band coverage is accomplished with a small footprint of (16 × 16 × 0.8) mm 3 . The decreased dimensions of the filter result in a group delay of 0.5 ns for maximum filter performance. By loading CSRR into the structure, it established double negative property in the simulated frequency range of interest. A vector network analyzer is used to evaluate system characteristics such as operational bandwidth, return loss, and insertion loss (VNA). The filter's electrical size (0.19 × 0.19)λ g compactness substantiates its application in 4G-LTE-WLAN/WiMaX standards.