Abstract
In this paper, parallel coupled meander lines (PCML) composite right/left-handed transmission line (CRLH-TL) based symmetrical quasi-0 dB coupled-line coupler is presented. Proposed coupler shows measured backward wave coupling level of 0.81 dB at frequency of 6.17 GHz with 3 dB fractional bandwidth (FBW) of 12.64%. Throughout the 3 dB frequency range (5.78–6.56 GHz), isolation and insertion loss of the coupler is better than 24 dB. Overall size of the proposed coupler is 19.6 × 12.1 mm. An equivalent lumped LC circuit model of the coupler is demonstrated. Measured results of the coupler show good agreement with the electromagnetic (EM) simulated and lumped LC circuit model simulated results, which validates proposed coupler design and its performance.
Author contribution: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Research funding: None declared.
Employment or leadership: None declared.
Honorarium: None declared.
Conflict of interest statement: The authors declare no conflicts of interest regarding this article.
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