Investigation of a Double-Negative Metamaterial-Loaded Helical Slow-Wave Structure: Equivalent Circuit Analysis Approach

This article presents a comprehensive theoretical investigation into a double-negative metamaterial (MTM)-loaded helical slow-wave structure (DNM-HSWS) employing an equivalent circuit analysis (ECA) approach considering the sheath-helix model of the helix. The study involves deriving dispersion and interaction impedance formulations, with a focus on analyzing the propagation and interaction characteristics of the structure. The practically feasible DNM-HSWS is designed and analyzed using CST-microwave studio software. A comparative analysis is conducted between theoretical and simulation results for the designed CST model, verifying the accuracy of the proposed theoretical investigation for the DNM-HSWS. Beyond validation, this study highlights the practical utility of the proposed theoretical investigations and the designed DNM-HSWS within the domain of MTM-inspired vacuum electron device (VED) applications. The findings contribute to advancing the understanding and application of MTM-loaded structures for improved performance in microwave devices.