This paper presents an effective modeling methodology for Ultra-wideband (UWB) antennas. The methodology is based on augmenting an existing narrow-band model with a macro-model while simultaneously perturbing component values of the narrow-band model. The narrow-band model is an empirical-based circuit and the macro-model described by rational functions is determined using data fitting approach...

silicon nanowire (sinw) arrays were produced by electroless method on polycrystalline si substrate, in hf/ agno3 solution. although the monocrystalline silicon wafer is commonly utilized as a perfect substrate, polycrystalline silicon as a low cost substrate was used in this work for photovoltaic applications. in order to study the influence of etching time (which affects the sinws length) on d...

In this paper, an elaborate broadband model for the air-core winding is created based on the partial element equivalent circuit (PEEC) approach in order to study the internal overvoltage under the lightning transients. Because the large scale of the resulting model makes it difficult to be solved directly, the waveform relaxation method combined with the overlapping partitioning techniques is u...

A broadband Circuit Analogue (CA) absorber using double-circular-loop array is investigated in this paper. A simple equivalent circuit model is presented to accurately analyze this CA absorber. The circuit simulation of the proposed model agrees well with full-wave simulations. Optimization based the equivalent circuit model, is applied to design a single-layer circuit analogue absorber using d...

Silicon nanowire (SiNW) arrays were produced by electroless method on polycrystalline Si substrate, in HF/ AgNO3 solution. Although the monocrystalline silicon wafer is commonly utilized as a perfect substrate, polycrystalline silicon as a low cost substrate was used in this work for photovoltaic applications. In order to study the influence of etching time (which affects the SiNWs length) on d...

In this paper a new procedure for designing forward-wave directional couplers using periodic shunt short circuited stubs is proposed. A new type of cell using these stubs, which enlarge the phase difference between even- and odd modes of a uniform microstrip coupled line is introduced. Using the equivalent circuit model for even- and odd-modes of the proposed cell, the elements of the  ABCD tra...

An intelligent design method of double screen frequency selective surfaces (FSSs) is addressed in this paper. The employed unit cell is composed of two metallic screens, which are printed on both sides of a substrate. The presented non-trial-and-error approach is investigated based on the separate design of each screen. With the help of some physical intuition and an equivalent circuit model, i...

a mathematical modelling for more-winding single-phase transformer is presented. the incidence matrix-which gives the informations about the connection of the ends of the windings between the nodes-is multiplied leftside and rightside with the inverse of the inductance matrix of the more winding transformer. the result is a matrix which gives the relationship between nodes potentials and nodes ...

In this paper, as an application of fuzzy matroids, the fuzzifying greedy algorithm is proposed and an achievableexample is given. Basis axioms and circuit axioms of fuzzifying matroids, which are the semantic extension for thebasis axioms and circuit axioms of crisp matroids respectively, are presented. It is proved that a fuzzifying matroidis equivalent to a mapping which satisfies the basis ...