Second order microstrip bandpass filter design based on square resonator for 5G sub-6 GHz band

Abstract

Abstract A simple procedure for designing a highly selective microstrip bandpass filter of second order is presented in this paper. The proposed filter is composed of two principal square open-loop resonators and designed with planar structures on a Roger substrate. It is intended for 5G applications, especially for Sub-6 GHz range frequency [3.5–3.8 GHz]. The suggested band pass filter has a very attractive compact size of 7 mm × 15.46 mm. The performance of this simple miniaturized filter, which is characterized by high selectivity in the band of interest, can be seen from its important characteristics: Adaptation, Transmission and Coupling Coefficients. The electromagnetic simulations and measurement results are in good agreement, which validates the design idea and procedure.