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arXiv · 2111.02087

Antenna De-Embedding in FDTD Using Spherical Wave Functions by Exploiting Orthogonality

Leonardo Mörlein·Lukas Berkelmann·Dirk Manteuffel
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Abstract

De-embedding antennas from the channel using Spherical Wave Functions (SWF) is a useful method to reduce the numerical effort in the simulation of wearable antennas. In this paper an analytical solution to the De-embedding problem is presented in form of surface integrals. This new integral solution is helpful on a theoretical level to derive insights and is also well suited for implementation in Finite Difference Time Domain (FDTD) numerical software. The spherical wave function coefficients are calculated directly from near-field values. Furthermore, the presence of a near-field scatterer in the de-embedding problem is discussed on a theoretical level based on the Huygens Equivalence Theorem. This makes it possible to exploit the degrees of freedom in such a way that it is sufficient to only use out-going spherical wave functions and still obtain correct results.

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Leonardo Mörlein, Lukas Berkelmann, Dirk Manteuffel. 2021-11-03. Antenna De-Embedding in FDTD Using Spherical Wave Functions by Exploiting Orthogonality. https://arxiv.org/abs/2111.02087

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