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Abstract Fractional Calculus is a branch of mathematical analysis that studies the non-integer-order differentiation and integration. The application of fractional calculus in the field of electromagnetics has been given much attention in the last few decades. Indeed, imposing fractional calculus in electromagnetic problems enables us to study the intermediate behavior between the various integer-order responses thus leading to new ideas, promising results and better understanding of such intricate engineering problems. In this thesis, we focus on investigating the effect of imposing fractional-order time derivatives on the conventional Maxwell’s equations that control the behavior of electromagnetic fields. We study in the beginning some special cases of Maxwell’s equations in the fractional-order time domain and illustrate that the integer-order case is considered as a special case. We apply the modified formulas of Maxwell’s equations on an example of a rectangular waveguide showing that imposing the fractional parameters gives some degrees of freedom to control the characteristics of the waveguide, such as the cutoff frequency and the intrinsic impedance which is shown to be complex in value. The concept of the fractional curl operator introduced a few years ago provides additional intermediate solutions to an electromagnetic problem rather than the canonical solutions. In this thesis, this concept of fractional curl operator is restudied, taking into consideration the fractional-order time derivatives in Maxwell’s equations. The modified analysis adds two extra fractional parameters onto the conventional curl concept which increases the number of degrees of freedom to control or optimize the design problem. As an example, the modified form of the fractional curl operator is applied to the operation of a parallel-plate waveguide in the TM mode where several special cases are illustrated, showing the importance of the added parameters. For example, it is shown that the added parameters introduce a power loss term that can be used to model the frequency-dependent losses, although all resistive elements are neglected during the study. Moreover, this thesis demonstrates some fundamentals concerning the study of the Fractional-order Transmission Line (FTL) operation. Whereby the application of fractional calculus is shown to outperform the conventional domain. The transmission-line modeling (TLM) is a space- and time-discretizing method for the computation of electromagnetic fields based on the analogy between the electromagnetic field and a mesh of transmission lines. This analogy enables us to solve a network problem rather than a field problem. This thesis also restudies the TLM in the fractional order sense showing how to utilize it to solve some fractional-order differential equations. In all the work in this thesis, it is verified that the analysis of any problem in the conventional domain is a special case from the fractional-order study when all the fractional-orders are equal to “1”. |