A novel compact wideband bandstop filter design using a dual-mode square loop resonator

Abstract

In this paper, a novel compact wideband microstrip bandstop filter is presented by using a dual-mode square loop resonator having stepped impedance sections located at the lateral arms. The proposed resonator is directly connected to Input/Output (I/O) ports to obtain a wide stopband and loading elements are also employed to control the zeros and poles. The transmission-line model is used to explain the design methodology clearly. Simulated and measured responses show an excellent agreement. © 2016 IEEE.