IMPROVEMENT THE DESIGN OF MICROWAVE DUAL-BAND BPF BY DGS TECHNIQUE

This article presents a new method for designing a dualband bandpass filter at microwave frequency with improvement on filter characteristics like bandwidth, in band insertion loss and outband and decrease the neutral harmonics on stopband with using defected ground structure ( DGS) technique. The basic resonator, with a single passband, was designed using an open-circuit capacitor-coupled stripline resonator. An I-shape architecture was employed at the middle part of the basic resonator to create a dual-passband frequency response. Finally, the current density of the filter with DGS and without DGS is shown. Simulation results for the proposed filter include performance at 4.6 GHz and 7.3 GHz with respective bandwidths of 178 MHz and 155 MHz. Simulation results well match the characteristics of the fabricated filter. (C) 2016 Wiley Periodicals, Inc.