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arXiv · 2108.04691

Fundamental Limits on Substructure Dielectric Resonator Antennas

Binbin Yang·Jaewoo Kim·Jacob J. Adams
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Abstract

We show theoretically that the characteristic modes of dielectric resonator antennas (DRAs) must be capacitive in the low frequency limit, and show that as a consequence of this constraint and the Poincar\'{e} Separation Theorem, the modes of any DRA consisting of partial elements of an encompassing super-structure cannot resonate at a frequency that is lower than that of the encompassing structure. Thus, design techniques relying on complex sub-structures to miniaturize the antenna, including topology optimization and meandered windings, cannot apply to DRAs. Due to the capacitive nature of the DRA modes, it is also shown that the Q factor of any DRA sub-structure will be bounded from below by that of the super-structure at frequencies below the first self-resonance of the super-structure. We demonstrate these bounding relations with numerical examples.

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Binbin Yang, Jaewoo Kim, Jacob J. Adams. 2021-07-14. Fundamental Limits on Substructure Dielectric Resonator Antennas. https://arxiv.org/abs/2108.04691

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