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A novel finite-difference time domain (FDTD) algorithm named equivalent circuit FDTD (EC-FDTD) is realized, which introduces lumped elements from transmission line theory into Yee cell. It includes lumped elements such as series inductance and shunt capacitance in the right-handed materials, as well as shunt inductance and series capacitance in the left-handed materials. Due to its promising physical thoughts, it can be easily generalized to arbitrary dispersive materials including frequency selective surfaces and metamaterials. The technology of streaming single-instruction multiple-data (SIMD) extensions (SSE) was proposed by Intel and is currently utilized in personal computers. SSE is a kind of parallel speedup technology in one core. The speedup can be achieved four times in principle without changing hardware. Combined with SSE, the EC-FDTD can be apparently accelerated. Twice speedup is achieved in the tests of this paper. The algorithm of EC-FDTD is utilized to design the wideband metamaterials absorbers by employing the single square and double square loops loaded with the lumped resistors. The invisible radome has a great impact on reducing the radar cross section of the antenna out of band. The radome is designed with operating frequency to be 1 GHz and the absent bandwidth from 3 GHz to 9 GHz by the algorithm. And then these prototypes are fabricated and measured. From the comparative results, the correctness of EC-FDTD and the speedup of the SSE are both verified.

We experimentally investigate the discrete mode in the zero-average-refractive-index gap (the zero-n—gap) of the one-dimensional periodical structures containing left-handed materials (LHMs) and right-handed materials (RHMs). When the discrete mode conditions are satisfied in the zero-n gap, there are no discrete propagating modes, but the zero-n—gap completely vanishes. This behavior is attributed to the dispersive property of LHMs and RHMs. In addition, the theoretical expectation of the discrete modes with no sidelobes in the zero-n—gap never occurs in experiment because the LHMs is intrinsically dispersive.

A transmission line model capable of predicting the reflection phase of high impedance surfaces in normal incident is proposed. The surface impedance of high impedance surface （HIS） can be regarded as the effective capacitive impedance of patch array in parallel with the inductive impedance of substrate layer, and the effect of vias conductor can be ignored at normal incidence. Results of the a nalytical model agree well with the HFSS simulated results. HIS with different parameters are fabricated and tested, the reflection phase of HIS predicted using the transmission line model agree well with the measured results, which proves the validity of this transmission line model.

Magnetized plasma photonic crystals are artificial periodic structures composed of magnetized plasmas and dielectric structures (or vacuum).In this paper,the piecewise linear current density recursive convolution (PLCDRC) finite-difference time-domain (FDTD) method for magnetized plasmas is applied to study the magnetized plasma photonic crystals.The effect of parameters of magnetized plasma on electromagnetic band gap is presented.In time-domain,the electromagnetic propagation process and reflection/transmission electric field of Gaussian pulses through magnetized plasma photonic crystals are investigated.In frequency-domain,the reflection and transmission coefficients through magnetized plasma photonic crystals are computed.The results are discussed.

In this paper a kind of high impedance substrate surface covered with different dielectric layer is analyzed by periodic moment method, their band-gap diagrams are described. Meanwhile, the propagating property of surface wave of the high impedance ground plane with different dielectric covering is tested, the results of theoretic analysis are validated. Our results can be helpful for the design of high impedance ground plane with a dielectric cover layer.

The JEC finite-difference time-domain (JEC-FDTD) method is extended to three dimensional anisotropic dispersive media—the magnetized plasma. The problem which incorporates both anisotropy and frequency dispersion at the same time is solved for the electromagnetic wave propagation. The three dimensional JEC-FDTD formulations for anisotropic magnetized plasma are derived. The method is applied to the electromagnetic scattering of dihedral corner reflector and sphere-cone coated with anisotropic magnetized plasma. By simulating the interaction of electromagnetic wave with magnetized plasma, some numerical results are obtained, which indicate that an appropriate plasma coating may efficiently reduce the RCS of a metallic target.

Plasma photonic crystals are artificially periodic structures, which are compose d of plasmas and dielectric structures (or vacuum). In this paper, the piecewise linear current density recursive convolution (PLCDRC) finite-difference time-do main (FDTD) method is applied to study the plasma photonic crystals and those co ntaining defects. In time-domain, the electromagnetic(EM) propagation process an d reflection/transmission electric field of Gauss pulses passing through the pla sma photonic crystals are investigated. In frequency-domain, the reflection and transmission coefficients of the pulses through the two kinds of crystals are co mputed. The results illustrate that the plasma photonic crystals mostly reflect for the EM wave of frequencies less than the plasma frequency, and mostly transm it for EM wave of frequencies higher than the plasma frequency. In high frequenc y domain, the plasma photonic crystals have photonic band gaps, which is analogo us to the conventional photonic crystals.

The uniplanar compact photonic_bandgap (UC_PBG) is a periodic planar layered str ucture which is constructed in the microstrip structures. In this paper, the sub strate is regarded as an uniaxial anisotropic medium, and the UC_PBG is analyzed using the method of lines (MoL). The process of MoL is described in detail, som e UC_PBGs with different dielectric parameters are computed. It is shown that th e complete band gaps or even larger ones appear in dispersion diagram of those UC_PBGs.

The finite-difference time-domain(FDTD) method is extended to two dimensional anisotropic dispersive media-magnetized-plasma using Z transformation for the f ist time. The problem which incorporates both anisotropy and frequency dispersio n at the same time is solved for the electromagnetic wave propagation. The two d imensional FDTD formulations for anisotropic magnetized plasma are derived. The method is applied to the electromagnetic scattering of perfectly conducting cyli nder coated with anisotropic magnetized plasma. By simulating the interaction of electromagnetic wave with magnetized plasma, some bistatic numerical results ar e obtained, which indicate that an appropriate plasma coating may efficiently re duce the RCS of a metallic target.

A JEC finite-difference time-domain (JEC-FDTD) methodology for dispersive media is extended to anisotropic magnetized plasmas. The problem which incorporates both anisotropy and frequency dispersion at the same time is solved for the electromagnetic wave propagation. The JEC-FDTD formulation for anisotropic magnetized plasmas is derived. The high efficiency and accuracy of the method are confirmed by computing the reflection and transmission through a magnetized plasma layer, with the direction of the propagation parallel to the direction of the biasing field. A comparison with frequency-domain analytic results is included.

A novel finite-difference time-domain (FDTD) method, called piecewise linear current density recursive convolution method,is developed for dispersive media. The formulation of this method is derived using the convolution relationship between the current density and the electric field. The high accuracy and efficiency of this method are confirmed by computing the reflection and transmission coefficients of electromagnetic waves through a collisional plasma slab in one dimension.

A PLJERC-FDTD algorithm is applied to the study of the scattering of perfectly conducting cube covered with homogeneous isotropic plasmas. The effects of plasma thickness, density and collision frequency on the radar cross section(RCS) of the conducting cube scatterer have been obtained. The results illustrate that the plasma cloaking can greatly reduce the RCS of radar targets, and the RCS of the perfectly conducting cube scatterer decreases with increasing plasma thickness when the plasma frequency is greatly less than the electromagnetic(EM) wave frequency; the RCS of the perfectly conducting cube scatterer decreases with increasing plasma thickness and plasma collision frequency when the plasma frequency is almost half as much as the EM wave frequency; the effects of plasma thickness and collision frequency on the RCS of the perfectly conducting cube scatterer is small when the plasma frequency is close to the EM wave frequency.

An auxiliary differential equation finite-difference time-domain (ADE-FDTD) methodology for anisotropic magnetized plasmas is derived. The method is based on a difference approximation of the auxiliary differential equation. A comparison with the JEC method is included. The CPU time saving by several times and accuracy of the method are confirmed by computing the reflection and transmission through a magnetized plasma layer, with the direction of propagation parallel to the direction of the biasing field.