A new method modifying the frequency dependent alternating direction implicit finite difference time domain (FD–ADI– FDTD) is presented. The method can improve the accuracy of FD–ADI–FDTD without significant increase of computational costs. The proposed method is validated by numerical tests. Index Terms ADI–FDTD, Debye media, Accuracy of FDTD

Effects of material and configuration of the internal wall on the performance of wideband channel are investigated by using the Finite Difference Time-Domain (FDTD) method. The indoor wideband channel characteristics, such as the path-loss, Root-Mean-Square (RMS) delay spread and number of the multipath components (MPCs), are presented. The simulated results demonstrate that the path-loss and M...

Patch antennas have emerged rapidly with advancement of communication technology. For antenna design purposes, Finite difference time domain (FDTD) method is a commonly used. This paper focuses on the interaction among elements of MIMO antenna also known as mutual coupling using FDTD method. An M shape is introduced and with placement of isolating structure, round about 12dB of isolation is inc...

The channel capacity of the indoor multiple input multiple output (MIMO) system is investigated with consideration of the effects of the wall by using a hybrid method of the finite difference time domain (FDTD) method and the method of moments (MoM). Firstly, the effects of wall material on indoor MIMO channel capacity are investigated according to the physical parameters of the wall, i.e. the ...

In this contribution an enhanced version of the Finite Difference Time Domain (FDTD) method is used to calculate the field penetration and Specific Absorption Rate (S-AR) pattern for a current sheet applicator used in Hyperthermia treatment. The FDTD method uses modified equations to rigorously model three dimensional dielectric boundaries and a nonuniform grid for computational efficiency. Res...

We consider the finite element approximation of the solution to a singularly perturbed second order differential equation with a constant delay. The boundary value problem can be cast as a singularly perturbed transmission problem, whose solution may be decomposed into a smooth part, a boundary layer part, an interior/interface layer part and a remainder. Upon discussing the regularity of each ...

The scalar difference equation xn+1 = fn(xn, xn−1, · · · , xn−k) may exhibit symmetries in its form that allow for reduction of order through substitution or a change of variables. Such form symmetries can be defined generally using the semiconjugate relation on a group which yields a reduction of order through the semiconjugate factorization of the difference equation of order k + 1 into equat...

The paper presents the results of 3D FDTD modeling of a 915 MHz cylindrical structure with a spherical load (fruit). Three different configurations of the loops exciting the TM01l mode are analyzed. The coupling is shown not to be sensitive to the load’s temperature and to the type of the fruit.

We define a finite-differences derivative operation, on a non uniformly spaced partition, which has the exponential function as an exact eigenvector. We discuss some properties of this operator and we propose a definition for the components of a finite-differences momentum operator. This allows us to perform exact discrete calculations.

We study the semantic difference operator defined in [16] for ALN . We give a polynomial-time algorithm to compute it. We compare it with the syntactic difference operator defined in [7], for which we also give a polynomial-time algorithm for ALN .