Design of Small Antennas with Optimized Embedded Loads Using the Characteristic Modes

This paper presents the design of Electrically Small Antennas (ESAs) with embedded reactive loads. The reactive loads inside the antenna serves in controlling the currents that are supported by its structure in order to miniaturize and match the antenna in a wideband. The manipulation of the antenna currents is achieved by controlling the modal currents of the antenna or more specifically the Characteristic Modes (CMs). The CMs provides deep physical insights of the behavior of the antenna in terms of its resonance and the reactive interaction between the modes that are supported by its structure. Based on modal interpretation it would then be possible to optimally manipulate the antenna currents so that it could be matched in a wide bandwidth.

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