A Compact Tunable Dual-Stop-Band Filter Based on DMS and DGS

Abstract

Abstract-In this paper, a compact tunable dual-stop-band filter is proposed. The proposed filter is based on the combination of double H-shaped defected ground structure (HDGS) and E-shaped defected microstrip structure (EDMS). The loaded HDGS/EDMS varactor diode is introduced to realize the tunable dual-stop-band filter. The equivalent-circuit models and theoretical analysis of the proposed structure are presented; also its performance evaluation is compared with traditional structure. The proposed filter has the characteristic of two independently adjustable stopbands and wide tuning range. EDMS also shows size reduction up to 38% compared with the Tshaped defected microstrip structure. The measured performance of the tunable dual-stop-band filter agrees well with the simulation results.

Rotational circular split ring resonator array loaded CPW for dual notch and wide bandstop applications

“…Some of these designs integrate the frequency‐notching components within the device, thereby greatly optimizing the required area. Most of the designs proposed in are frequency scalable, however, they require several stages to achieve significant rejection band and therefore can be relatively bulky for certain applications. A completely new approach of designing stop band filter was proposed in utilizing the subwavelength resonance phenomenon of the split ring resonator (SRR) loaded beneath the slots of the CPW, resulting in highly compact, frequency scalable design.…”

“…Traditional techniques of filter realization like quarter or half‐wavelength stubs , chip capacitor, or cascaded rejection band filters suffers from certain fundamental problems like increased device area, narrow rejection band, flat pass to stop band transition (resulting low Quality factor), and high insertion loss in the pass band . Several design strategies have been proposed in open literature to overcome these limitations using the concept of photonic band‐gap structures , by etching holes or shaped slots on the ground plane commonly known as defected ground structures using microstrip or coplanar waveguide (CPW) technology. Some of these designs integrate the frequency‐notching components within the device, thereby greatly optimizing the required area.…”