Common-mode suppressed differential bandpass filter based on open complementary split ring resonators fabricated in microstrip technology without ground plane etching

A differential (or balanced) bandpass filter based on open complementary split ring resonators (OCSRRs) coupled through admittance inverters is presented in this article. Pairs of OCSRRs are symmet- rically placed in a mirror configuration between the strips of the differential line and are modeled...

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Bibliographic Details
Authors: Vélez, Paris|||0000-0001-6502-5987, Durán-Sindreu, Miguel|||0000-0002-1459-9857, Naqui Garolera, Jordi|||0000-0001-5660-1516, Bonache Albacete, Jordi|||0000-0002-7225-5737, Martín, Ferran|||0000-0002-1494-9167
Format: article
Publication Date:2014
Country:España
Institution:Universitat Autònoma de Barcelona
Repository:Dipòsit Digital de Documents de la UAB
Language:English
OAI Identifier:oai:ddd.uab.cat:163102
Online Access:https://ddd.uab.cat/record/163102
https://dx.doi.org/urn:doi:10.1002/mop.28211
Access Level:Open access
Keyword:Split ring resonators
Differential bandpass filters
Microstrip technology
Description
Summary:A differential (or balanced) bandpass filter based on open complementary split ring resonators (OCSRRs) coupled through admittance inverters is presented in this article. Pairs of OCSRRs are symmet- rically placed in a mirror configuration between the strips of the differential line and are modeled by means of two series connected parallel resonators. For the differential (odd) mode, there is a virtual ground at the connecting plane between the OCSRR pairs, and the structure is roughly described by the canonical model of a bandpass filter, consisting of a cascade of shunt resonators coupled through admittance inverters. It is demonstrated that, through a proper design of the OCSRR stages, the common mode noise in the vicinity of the differential filter pass band can be efficiently suppressed. Due to the differential mode operation of the filter, it is not necessary to incorporate metallic vias to ground the OCSRRs. Moreover, as compared to other differential filters based on OCSRRs, defected ground structures are not present in the proposed filters. To illustrate the potential of the approach, two balanced bandpass filters are designed, fabricated, and characterized.