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One-directional weakly conditionally stable finite-difference time-domain (WCS-FDTD) method is extended to solve electromagnetic problems in linear dispersive media by virtue of piecewise linear recursive convolution (PLRC) technique. This proposed method provides similar accuracy to PLRC alternating direction implicit (ADI) FDTD approach, yet consumes less computational time and less memory. This proposed method is particularly suitable for solving problems in linear dispersive materials with fine features along two spatial directions. [ABSTRACT FROM PUBLISHER]

In this work we investigate three different artificial ground planes for microstrip antenna design, which are useful for different applications. The three different ground plane configurations studied include: (i) conventional dielectric substrate backed by a perfect conductor; (ii) a loop type of artificial magnetic conductor (AMC); and a spiral-type of AMC. Both the loop and spiral types of AMCs tend to lower the resonant frequency of the microstrip patch antenna (MPA), as compared to that of the dielectric substrate, for the linearly polarized case. However, the spiral AMC can be used to realize circular polarization as well, at a different frequency band, hence, is useful for designing dual-band dual-polarization microstrip antennas. [ABSTRACT FROM AUTHOR]

The power/ground bounce seriously affects circuit performance. Several methods have been used to simulate it. These methods ranged from simple lumped circuit models to full-wave (dynamic) three-dimensional Maxwell equations simulators. In this paper, the method of time-domain full-wave analysis is used to simulate the noise caused by three types of different excited sources in the power distribution networks (PDNs), to research the effect of source types on the noise and to analyze the effect of source property, dielectric materials, and boundary conditions on noise voltage and mutual impedance between ports. [ABSTRACT FROM AUTHOR]

An accurate model of composite right/left handed transmission line (CRLH-TL) is used to design an arbitrary dual-band branch-line coupler (BLC). A pure left handed (LH) cell is not possible due to unavoidable parasitic series inductance and shunt capacitance effects, which are taken into consideration in the accurate model. With respect to a dual-band BLC designed with a conventional model, the coupler designed with the accurate model uses less chip components and achieves perfect performance, which is demonstrated by simulation and measurement results. [ABSTRACT FROM AUTHOR]

A compact ultra-wideband (UWB) bandpass filter is presented by using a modified stepped impedance resonator (SIR) and defected ground structures (DGSs). The modified SIR is to generate multiple-resonant peaks within the UWB passband and tighten the coupling with the feed-lines. Then, the DGSs are to enhance the coupling degree of coupled lines and realize wide stopband. From simulated and measured results, the filter shows good UWB performance, including low insertion loss within the passband, a small group delay variation, and a wide stopband with -20 dB attenuation up to 19.6 GHz. [ABSTRACT FROM AUTHOR]

A compact planar sub-wavelength array is proposed, which has planar antenna elements etched with defect oval rings on the surface. The array demonstrates a property of 1/20 wavelength super-resolution combined with time-reversed electromagnetic waves. This design is simple in structure, easy to integrate and convenient for the printing design of circuit boards. [ABSTRACT FROM AUTHOR]