Summary
International Symposium on Antennas and Propagation
2012
Session Number:4E3
Session:
Number:4E3-3
Eigenmodes Analysis in Drude-type Dispersive EBG Structures in Frequency Domain
Amin Gul Hanif, Takuji Arima, Toru Uno,
pp.-
Publication Date:2012/10/29
Online ISSN:2188-5079
Summary:
Recently, remarkable progress has been made in the study of electromagnetic band gap (EBG) structures due to their various applications in optics, microwave, and antenna engineering [1]. The band structure of EBG structures has been researched for frequency-independent or non-dispersive materials. Lately, there is an intensive interest in the analysis of dispersive EBG structures for novel applications. Therefore, accuracy in modeling of the band structure of EBGs composed of dispersive materials is important to accurately analyze the wave propagation phenomena over a wide range of frequencies in microwave and optical fields. Several numerical methods have been used for the band structure computation of two-dimensional (2D) EBG structures. The most commonly used methods are the plane-wave expansion (PWE) method [2], the finite-difference time-domain (FDTD) method [3-5], and the finite-difference frequency-domain (FDFD) method [1, 6]. The PWE method is very simple and easy to apply. However, the resultant matrix of the PWE method is dense and large, therefore making its computation heavy for large problems. The FDTD method is a widely-used electromagnetic computational method, which is also applicable for dispersive materials [5]. However, in some cases, the FDTD method does not give accurate results for the band structure calculation of EBG media because there is a chance of losing the resonant frequencies if the excitation and monitor points are not properly located in the calculation domain [3, 6]. In this paper, we use a new 2D FDFD algorithm to calculate the band structure and electric field distribution of eigenmodes of 2D EBG structure composed of Drude-type dispersive media. This algorithm uses only the eigenvalue equation, thus, all of the eigenfrequencies can be computed accurately for every band point of irreducible Brillouin zone. To validate this method, it is compared with the FDTD method which shows high accuracy and stability.