DESIGN OF COMPACT COPLANAR BANDSTOP FILTER COMPOSED ON OPEN-LOOP-RING RESONATOR AND DEFECTED GROUND STRUCTURE (DGS)

作者：Batmanov Anatoliy^*; Boutejdar Ahmed; Omar Abbas; Burte Edmund

来源：Microwave and Optical Technology Letters, 2010, 52(2): 478-483.

DOI：10.1002/mop.24905

• bandstop filter (BSF)
• open-loop-ring resonator
• defected ground structure (DGS)
• CPW
• microstrip filter

Design of a novel compact bandstop filter composed on an open-loop-ring resonator and a defected ground structure (DGS) for coplanar waveguide is proposed and investigated. A simple coplanar open-loop-ring resonator has been designed and tested for the stop-band front 3.9 to 4.3 GHz with tree transmission zeroes inside the stop-band. Two almost symmetrical poles are obtained on both sides of the stop-band. Then the proposed broad band bandstop filter based on the one open-loop-ring resonator has been transformed to the bandstop filter with a narrower stop-band but with improved pass- and stop-band characteristics. It is realized by adding a conventional rectangular DGS slot inside the open-loop-ring. The equivalent circuit model has been proposed to describe the behaviour of the bandstop filters. The improved bandstop filter introduces the stop-band from 3.75 to 5.3 GHz with two transmission zeroes within and more than -20 dB rejection. The total size of the proposed structure is 13.8 x 13.4 mm(2). Both bandstop filters have been fabricated and measured. Measurements are in good agreement with simulation results.

• 出版日期2010-2