WCIP analysis of arbitrary shaped lumped metamaterial medium using a paint interface

In this paper, a rectangular metallic ring FSS (Frequency Selective Surfaces) with parallel metallic strips for multi band applications are characterized by the WCIP (Wave Concept Iterative Procedure) method. The proposed FSS structures are made of metallic elements that are simultaneously independent in the spatial domain and uncoupled in the spectral domain. Thus the FSS multiband behavior can be achieved only by a building process based on independent metallic elements in both domains. The resonant characteristics of the proposed FSS are determined. The structure shows three resonant frequencies when the incident wave is x-polarized and three resonant frequencies when the source is polarized in the orthogonal direction. A variation in the length of the strips and the rectangular ring allows a fine tuning in the FSS resonant frequencies to give raise to tuned bandwidths. The suppression of a resonant frequency can be insured either by the elimination of the responsible metallic strip or by the insertion of a PIN diode switch. Three FSS structures are manufactured and characterized. The FSS bandwidth can be enhanced in both perpendicular FSS exciting source directions by only varying the strips lengths and the ring dimensions to the corresponding resonant frequencies. A good agreement is obtained when the WCIP results are compared with the simulations of COMSOL Multiphysics software and experiment.

In this paper, we present the WCIP iterative procedure (wave concept iterative procedure) for solving continuity conditions in terms of waves rather than in term of tangential fields providing a mixed resolution in spatial and spectral domain taking the best advantage of each resolution domain and lower computation time. The spiral inductor with patterned ground shield is taken as an example of multi-layer structures; the results are in reasonably good agreement with the experimental data.

Computer programs for simulation of microwave structures are becoming accessible. However, to understand electromagnetic fields behavior and to comprehend the numerical model limitations, a solid theoretical basis and computational expertise to enable the implementation of the own programs remains indispensable. The wave concept iterative procedure, WCIP, is a numerical technique easy to understand, that can be implemented without great efforts. In this work the WCIP is applied to analysis of frequency selective surface, FSS, with Koch Island patch elements. Obtained numerical results are compared to others obtained by the use of Ansoft Designer <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">™</sup> software and to experimental ones.

We have studied a frequency selective surface (FSS) for a U-shaped geometry by a method called the Wave Concept Iterative Procedure (WCIP). The development of this method based on Fast modal transformation (FMT), for the FSS frequency response is presented in the results of a single resonance obtained by the WCIP method exhibit a resonance frequency at 5.6 GHz with a bandwidth of 2.75 GHz, when the structure is excited in the x direction by a plane wave at normal incidence, a resonance frequency at 11.6 GHz with a 414.61 MHz band when the structure is excited in the y direction. The simulation of the results obtained by the WCIP method are compared to the HFSS results and a good agreement is to score.

This work presents the frequency response analysis of a planar band pass filter using the WCIP method. The filter geometry is composed of a rectangular microstrip patch with a perforated complementary split ring resonator (CSRR). The investigation of the filter properties is done considering the perforated patch geometry printed on isotropic and anisotropic substrates. Simulations results are determined by WCIP method and HFSS software, for comparison purpose, for the filter resonant frequency, bandwidth, return loss, and insertion loss. A prototype of the proposed band pass filter printed on isotropic substrate was fabricated and measured. Simulation (WCIP and HFSS) and measurement results are in good agreement.

The wave concept iterative procedure (WCIP), already improved for planar circuits, is developed in this paper for cylindrical structures. The WCIP method has been applied with success to the scattering of an E‐polarisation plane wave on cylindrical strips. The results are in good agreement with previous works in the literature, and the calculation time involved is quite reasonable. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 403–406, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11074

A precise technique based on the wave concept iterative procedure (WCIP) and a fast mode transformation (FMT) is used to analyze a rectenna circuit. This global analysis is achieved by using surface impedance to model the non linear element (Schottky diode). These systems use the manufacturing processes of integrated circuits. In order to initialize the iterative procedure, an incident wave is defined in spectral domain. The numerical results are compared to those obtained with the measured one. The good agreement between simulated and published data justifies the design procedure.

This paper presents a new electromagnetic modeling of a via-hole using a Wave Concept Iterative Procedure. There are specific TM modes associated with the insertion of the via-hole influencing the incident and reflected waves, called the "via's modes". The formulation and results are presented considering the influence of one and two via's mode. The advantage of the model presented is the possibility to simulate planar circuits with a layer and a via-hole considering the effects of the field that propagates around the via.

The Wave Concept Iterative Procedure is validated for multi-layered substrate with frequency dependent and negative index media. By shifting the plasma frequency, reconflgurable fllter design is proposed with a center frequency tunability of 25%. Sensitivity to collisional plasma is proposed.

Wave concept iterative procedure (WCIP) is used for the determination of scattering characteristics of single and double metallic ring frequency selective surfaces (FSS). In the WCIP method, the analysis of the FSS is reduced to that of the unit cell. Basically, the WCIP method consists of scattering the incident waves at the interface and the reflection of the scattered waves by the closing ends of the periodic wall box containing the FSS unit cell. The use of the two dimensional fast Fourier transform algorithm results in a reduction of the running time and memory space. FSSs based on single and double metallic rings are analyzed by the WCIP method. A good agreement is observed between the WCIP results and the experimental results. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1324–1328, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23383

This paper presents the analysis of microstrip monopoles for applications in ultra wideband systems (UWB). Antenna structures using circular and semi annular ring patches are considered. The antennas are printed on a FR4 dielectric substrate and present truncated ground planes with a small cut beneath the microstrip line feeder to improve the antenna impedance matching. Results for return loss, resonant frequency, and impedance bandwidth are calculated using an iterative full-wave formulation based on the concept of electromagnetic waves (WCIP Method) and simulated using Ansoft HFSS software. Prototypes are fabricated and measured for validation purpose. Agreement is observed between WCIP calculated, HFSS simulated and measured results, confirming the WCIP method accuracy. The performance of the developed antennas are suitable for UWB and broadband systems.

A generalization of the wave concept iterative procedure method is proposed and used in the analysis of finite size and nonuniform frequency selective surfaces (FSS). The nonuniformity of the FSS is obtained by mixing different shapes of elements in the finite size FSS structures consisting of circular patch elements with and without radial slits. The shapes of the radial slit elements are defined according to a fractal-like formation rule, where the circular patch without radial slits is the generator. Single or multiband frequency performances can be obtained, enabling the design of reconfigurable FSS. In addition, a high stability of the incidence angle of the plane wave is confirmed. A good consistency is observed among theoretical, simulation, and experimental results.

Wave concept iterative procedure (WCIP) is used to analyze dual‐band and enhanced band frequency selective surfaces (FSS). In the metallic U‐shaped simple FSS, a fine‐tune of the two rejected bands is insured by varying independently the length of the two parallel U‐shaped FSS strips. The dual band response can also be obtained from the two‐level rectangular conducting patches FSS. An enhanced rejecting bandwidth is observed for FSS with two square ring printed on each substrate side. The WCIP results are successfully compared with measurements and HFSS results. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:836–839, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25073

Unlike the Earth, the Moon lacks is not protected from the atmosphere and global magnetic field, and will be directly exposed to complex radiation environments such as high-energy cosmic rays, solar wind, and the Earth’s magnetotail plasma. The surface of the Moon is covered with a thick layer of lunar soil, and the particles in the soil with a diameter between 30 nm–20 μm are called lunar dust. In the complex environments such as solar wind or magnetotail plasma, lunar dust carries an electric charge and becomes charged lunar dust. Charged lunar dust is prone to migration under the action of the electric field on the lunar surface. Charged migrated lunar dust is easy to adhere to the surface of instruments and equipment, resulting in visual impairment, astronauts’ movement disorders, equipment mechanical blockage, sealing failure, and material wear, which affects the lunar exploration mission. As an important lunar exploration landing site, the lunar south pole receives special solar radiation and produces a special dust plasma environment due to its special location. In order to provide an environmental reference for lunar south pole exploration, it is necessary to explore the characteristics of the dust plasma environment in the lunar south pole and its impact. In view of the lunar south pole environment, The Spacecraft Plasma Interactions Software (SPIS) software developed by the European Space Agency is used to carry out modelling and simulation in this work. Through the simulation, the logarithmic distribution of the lunar dust space density in a range of 0–200 m at the lunar south pole, the potential distribution near the lunar surface, and the spatial distribution characteristics of plasma electrons and ions are obtained. The obtained lunar dust space density and lunar surface potential are similar to the previous theoretical derivation and field detection data, so the simulation results have high reliability. The spatial potential distribution and the spatial density distribution of electrons and ions in the lunar environment with and without lunar dust are compared. Finally, the conclusions can be drawn as follows. The space potential increases with altitude increasing. The potential at 0–10 m near the lunar south pole is about –40 V, and the space potential at 100 m is about –20 V. The density of lunar dust in an altitude range below 10 m is 10&lt;sup&gt;7.22&lt;/sup&gt; m&lt;sup&gt;–3&lt;/sup&gt;–10&lt;sup&gt;4.66&lt;/sup&gt; m&lt;sup&gt;–3&lt;/sup&gt;. The electron density in the dust plasma near the lunar surface is 10&lt;sup&gt;5.47&lt;/sup&gt; m&lt;sup&gt;–3&lt;/sup&gt;, and the ion density is 10&lt;sup&gt;6.07&lt;/sup&gt; m&lt;sup&gt;–3&lt;/sup&gt;, and both increase with altitude increasing. Charged lunar dust affects the spatial distribution of lunar dust, mainly through affecting the distribution of the space electric field, which leads to difference in electron distribution, but has little effect on ions.

The study of the ac properties of nano-electronic systems is one of the most discussed topics recently. To understand the high-frequency electronic properties of carbon nanotubes we should understand passive, ac impedance of a 1D quantum system. In this paper we have tried to use CNT in Substrate Integrated Waveguide (SIW) and Modified SIW (MSIW) to decrease the electrical energy loss. For this, firstly some of the basic concepts about nanoscale electromagnetic properties and the qualitative difference in circuit behavior at nanoscale is presented. Secondly the electrical properties of carbon NanoTube and graphene which are the two most technologically advanced examples have been discussed. Thirdly a comparative study of conductive and substrate loss in SIW and MSIW has been conducted for CNT-graphene system and copper system. Thus we have suggested the use of CNTgraphene instead of copper in this substrate. Simulation results with the CST Microwave Studio show 70% reduction in conductive insertion loss and 40% reduction in total insertion loss in SIW. We have also studied the use of graphene and CNT in MSIW; the result of simulation with HFSS software is presented as well.