Design of dual band bandstop microstrip defected ground structure filter using adaptive neuro-fuzzy inference system

In this paper, a novel dual band bandstop filter (DBBSF) is presented. The filter is realized with defected ground structure (DGS). The adopted DGS shape in this work is merging of two consolidated P-shape DGS units which is used for first time in that purpose. The double center frequencies (fc1,2) could be controlled by adjusting the physical dimension parameters of the DGS unit. Determining these parameters needs using electromagnetic simulators in cumbersome time consuming optimization process. To overcome the problem, design curves are built using adaptive neuro-fuzzy inference system (ANFIS) to find the physical dimensions required for specific fc1,2 in extremely short time with high accuracy. DBBSF with predetermined specifications is designed using demonstrated methodology. Electromagnetic simulations reveal the fulfillment of the designed DBBSF to targeted specifications. Furthermore, the designed DBBSF is experimentally validated using the measurements of the fabricated circuit.