A Low-Cost Microwave Filter with Improved Passband and Stopband Characteristics Using Stub Loaded Multiple Mode Resonator for 5G Mid-Band Applications

Electronics

AbdulghaforA. Abdulhameed¹  FalihM. Alnahwi²  AbdulkareemS. Abdullah²  YasirI. A. Al-Yasir³  RaedA. Abd-Alhameed³ 

[1] Department of Applied Electronics and Telecommunication, Faculty of Electrical Engineering, University of West Bohemia, 301 00 Plzeň 3, Czech Republic;Department of Electrical Engineering, College of Engineering, University of Basrah, Basrah 61001, Iraq;Faculty of Engineering and Informatics, University of Bradford, Bradford BD7 1DP, UK;

关键词: microwave;    5G;    Stub Loaded Multiple Mode Resonator;    filter;    FR4;   

DOI  :  10.3390/electronics10040450

来源: DOAJ

【 摘 要 】

This paper presents the design and implementation of a printed circuit microwave band-pass filter for 5G mid-band applications, using a Stub Loaded Multiple Mode Resonator (SL-MMR) technique. The objective of this article is to introduce a low-cost microstrip filter with improved passband and stopband characteristics, based on a mathematical analysis of stub loaded resonators. The filter cost is reduced by selecting the low-cost FR4 dielectric material as a substrate for the proposed filter. Based on the transmission line model of the filter, mathematical expressions are derived to predict the odd-mode and the even-mode resonant frequencies of the SL-MMR. The mathematical model also highlights the capability of controlling the position of the SL-MMR resonant frequencies, so that the 5G sub-band that extends along the range (3.7–4.2 GHz) can perfectly be covered with almost a flat passband. At the resonance frequency, a fractional bandwidth of 12.8% (500 MHz impedance bandwidth) has been obtained with a return loss of more than 18 dB and an insertion loss of less than 2.5 dB over the targeted bandwidth. Furthermore, a pair of parasitic elements is attached to the proposed filter to create an additional transmission zero in the lower stopband of the filter to enhance the suppression of the filter stopband. The measured and simulation results are well agreed, and both reveal the acceptable performance of the stopband and passband characteristics of the filter.

【 授权许可】

Unknown