47 citations · 119 across the 9 of their papers we have counts for
10 papers
An Accurate Analytic Model for Traveling Wave Tube Dispersion Relation
Ahmed F. Abdelshafy, Filippo Capolino, Alexander Figotin
Abstract -- We construct an analytical model for the dispersion of the hot modes in a traveling wave tube (TWT) based on the Lagrangian field theory, upgrading its constants to be…
Experimental Demonstration of a New Oscillator Concept Based on Degenerate Band Edge in Microstrip Circuit
Dmitry Oshmarin, Ahmed F. Abdelshafy, Alireza Nikzamir +2
The first experimental demonstration of an oscillator based on a periodic, resonant microstrip circuit with a degenerate band edge (DBE) is presented. The DBE is a fourth-order exc…
Exceptional Degeneracy in a Waveguide Periodically Loaded with Discrete Gain and Radiation Loss Elements
Ahmed F. Abdelshafy, Tarek Mealy, Ehsan Hafezi +2
We demonstrate that a periodic waveguide comprising of uniform lossless segments together with discrete gain and radiating elements supports exceptional points of degeneracy (EPDs)…
High Power Backward Wave Oscillator using Folded Waveguide with Distributed Power Extraction Operating at an Exceptional Point
Tarek Mealy, Ahmed F. Abdelshafy, Filippo Capolino
The concept of exceptional point of degeneracy (EPD) is used to conceive a degenerate synchronization regime that is able to enhance the level of output power and power conversion…
Exceptional Degeneracies in Traveling Wave Tubes with Dispersive Slow-Wave Structure Including Space-Charge Effect
Kasra Rouhi, Robert Marosi, Tarek Mealy +3
The interaction between a linear electron beam and a guided electromagnetic wave is studied in the contest of exceptional points of degeneracy (EPD) supported by such an interactiv…
Exceptional Point of Degeneracy in Linear-Beam Tubes for High Power Backward-Wave Oscillators
Tarek Mealy, Ahmed F. Abdelshafy, Filippo Capolino
Abstract An exceptional point of degeneracy (EPD) is induced in a system made of an electron beam interacting with an electromagnetic (EM) guided mode. This enables a degenerate sy…
Distributed Degenerate Band Edge Oscillator
Ahmed F. Abdelshafy, Dmitry Oshmarin, Mohamed A. K. Othman +2
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 d…
Exceptional Point of Degeneracy in Backward-Wave Oscillator with Distributed Power Extraction
Tarek Mealy, Ahmed F. Abdelshafy, Filippo Capolino
We show how an exceptional point of degeneracy (EPD) is formed in a system composed of an electron beam interacting with an electromagnetic mode guided in a slow wave structure (SW…
Exceptional Points of Degeneracy in Periodic Coupled Waveguides and the Interplay of Gain and Radiation Loss: Theoretical and Experimental Demonstration
Ahmed F. Abdelshafy, Mohamed A. K. Othman, Dmitry Oshmarin +2
We present a novel paradigm for dispersion engineering in coupled transmission lines (CTLs) based on exceptional points of degeneracy (EPDs). We develop a theory for fourth-order E…
Exceptional Points of Degeneracy Induced by Linear Time-Periodic Variation Hamidreza
Hamidreza Kazemi, Mohamed Y. Nada, Tarek Mealy +2
We present a general theory of exceptional points of degeneracy (EPD) in periodically time-variant systems that do not necessarily require the presence of loss or gain, and we show…