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arXiv · 1401.0676

Generalized Coupled-line All-Pass Phasers

Shulabh Gupta·Qingfeng Zhang·Lianfeng Zou·Li Jun Jiang·Christophe Caloz
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Abstract

Generalized coupled-line all-pass phasers, based on transversally-cascaded (TC), longitudinally-cascaded (LC) and hybrid-cascaded (HC) coupled transmission line sections, are presented and demonstrated using analytical, full-wave and experimental results. It is shown that for N commensurate coupled-line sections, LC and TC phasers exhibit N group delay peaks per coupled-line section harmonic frequency band, in contrast to the TC configuration, which exhibits only one peak within this band. It is also shown that for a given maximum achievable coupling-coefficient, the HC configuration provides the largest group delay swing. A wave-interference analysis is finally applied to the various coupled-line phasers, explaining their unique group delay characteristics based on physical wave-propagation mechanisms.

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Shulabh Gupta, Qingfeng Zhang, Lianfeng Zou, Li Jun Jiang, Christophe Caloz. 2014-01-03. Generalized Coupled-line All-Pass Phasers. https://doi.org/10.1109/tmtt.2015.2397445

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