This paper presents the modeling of hemoglobin at optical frequency (250 nm - 1000 nm) using the unconditionally stable fundamental alternating-direction-implicit finite-difference time-domain (FADI-FDTD) method. An accurate model based on complex conjugate pole-residue pairs is proposed to model the complex permittivity of hemoglobin at optical frequency. Two hemoglobin concentrations at 15 g/...

We have developed a systematic design process for recently proposed slanted grating couplers (SGCs) that operates in the strong coupling regime. Based on rigorous analysis of SGC properties, this design process utilizes the k-vector diagram and a rigorous grating leaky-mode solver to intentionally enforce the phase-match and Bragg conditions. We demonstrate that the resultant SGC designs have p...

To model periodic structures with oblique incident waves/scan angles in FDTD, the field transformation method is successfully used to analyze their characteristics. In the field transformation method, Maxwell’s equations are Floquet-transformed so that only a single period of infinite periodic structure can be modeled in FDTD by using periodic boundary conditions (PBCs). A new discretization me...

In the present work we propose a strategy for developing reusable multi-model simulation library for solving Finite-Difference Time-Domain (FDTD) problem for Maxwell’s equations. The described EMTL (Electromagnetic Template Library) architecture is based on the selection of a small number of primitive low-level physical and numerical concepts which are used as parameters and building blocks for...

SUMMARY The Finite-Difference Time-Domain (FDTD) technique is presented in this paper as an estimation method for radio propagation prediction in large and complex wireless local area network (WLAN) environments. Its validity is shown by comparing measurements and Ray-trace method with FDTD data. The 2GHz (802.lIb/g) and 5GHz (802.lIa) frequency bands are used in both the calculations and exper...

In this paper, a new algorithm for studying elastic wave propagation in the phononic crystals is presented. At first, the displacement-based forms of elastic wave equations are derived and then the forms are discretized using finite difference method. So the new algorithm is called the displacement-based finite difference time domain (DBFDTD). Three numerical examples are computed with this met...

This paper introduces an automatic tuning method for the tiling parameters required in an implementation of the three-dimensional FDTD method based on time-space tiling. In this tuning process, an appropriate range for the tile size is first determined by trial experiments using cubic tiles. The tile shape is then optimized by using the Monte Carlo method. The tiled FDTD kernel was multi-thread...

This paper describes Meep, a popular free implementation of the finite-difference time-domain (FDTD) method for simulating electromagnetism. In particular, we focus on aspects of implementing a full-featured FDTD package that go beyond standard textbook descriptions of the algorithm, or ways in which Meep differs from typical FDTD implementations. These include pervasive interpolation and accur...

In modern MRI, patients are exposed to strong, rapidly switched magnetic field gradients that may be able to elicit nerve stimulation (1-14). This paper provides the numerical results of an investigation into induced current spatial distributions inside human tissue when exposed to these pulsed magnetic field gradients. Conventional FDTD methods are unable to model these effects as the effectiv...