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arXiv · 2002.00857

Distributed Degenerate Band Edge Oscillator

Ahmed F. Abdelshafy·Dmitry Oshmarin·Mohamed A. K. Othman·Michael M. Green·Filippo Capolino
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Abstract

We propose a new class of oscillators by engineering the dispersion of two-coupled periodic waveguides to exhibit a degenerate band edge (DBE). The DBE is an exceptional point of degeneracy (EPD) of order four, i.e., representing the coalescence of four eigenmodes of a waveguide system without loss and gain. We present a distributed DBE oscillator realized in periodic coupled transmission lines with a unique mode selection scheme that leads to a stable single-frequency oscillation, even in the presence of load variation. The DBE oscillator potentially leads to a boost of the efficiency and performance of RF sources, thanks to the unique features associated to the EPD concept. This class of oscillators is promising for improving discrete-distributed coherent sources and can be extended to radiating structures to achieve a new class of active integrated antenna arrays.

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Ahmed F. Abdelshafy, Dmitry Oshmarin, Mohamed A. K. Othman, Michael M. Green, Filippo Capolino. 2020-02-03. Distributed Degenerate Band Edge Oscillator. https://arxiv.org/abs/2002.00857

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