volume | PIER Journals

Abstract

To address the need to differentiate between dielectric and perfect electric conductor (PEC) conformal methods in the finite-difference time-domain (FDTD), this study proposes a conformal approach based on the harmonic mean to achieve a unified formulation. In this approach, the relevant electromagnetic parameters are weighted using harmonic mean weighting, enabling a conformal implementation within the FDTD framework. Both dielectric and PEC conformality are incorporated into a single mathematical framework, allowing for a unified treatment in the FDTD. The proposed method provides a consistent formulation that can be seamlessly integrated with standard FDTD procedures while ensuring high compatibility and accuracy of the results. The conformal method based on harmonic mean requires only 60% of the computational time and 36% of the memory compared to the CST method, indicating its high computational efficiency. Furthermore, it demonstrates strong applicability to complex biological models, such as specific absorption rate (SAR) calculations in the human head. This approach is particularly well suited for RF device design and biomedical applications, offering improved modeling efficiency and reliability.

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Dr. Cuihua Li

Dr. Haofeng Wang

Dr. Jun Zheng

Professor Minquan Li