Resonant Frequency Of Microstrip Antenna Research Articles

A new approach for CAD modelling of resonant frequency of microstrip antenna using multigene genetic programming

This paper develops a formula for the resonant frequency of microstrip antenna (MSA) using multigene genetic programming (MGGP). As proof of concept, it considers rectangular and circular MSAs. Then it applies the technique to annular ring and C-shaped MSAs. Compared with simulated and earlier reported results, the root mean square error remains below 0.2% in each case.

A Novel Compact Microstrip Antenna with an Embeddedλ/4 Resonator

In this paper, a novel design of compact microstrip antenna (MA) using an embeddedλ/4 resonator is presented. By utilizing the strong coupling between theλ/4 resonator and the radiation patch of MA, the resonant frequency of MA can be decreased. Besides, theλ/4 resonator is embedded in the patch, which does not enlarge the whole size of MA. Therefore, a compact antenna can be realized. In this paper, after the principle is stated, a sample antenna has been manufactured and measured to prove the predicted characteristics of our proposed antenna. The measurement agrees well with the simulation. Hence, the proposed method in this paper is quite suitable for the design of a compact antenna.

IMPLEMENTASI JARINGAN SYARAF TIRUAN DALAM MEMPREDIKSI FREKUENSI RESONANSI ANTENA MIKROSTRIP

The resonant frequency of an antenna is determined by the dimensional parameters and permittivity of the antenna substrate. Generally, to get the resonant frequency, a complex mathematical formula is needed to solve. For this reason, an intelligent method is offered to determine the resonant frequency more easily. In this study, an artificial neural network method with Backpropagation algorithm is used to overcome the problem. The data used were consisting of 80 training data and 15 testing data. The results have shown that the artificial neural network learning method with the backpropagation algorithm was successfully utilized to calculate the resonant frequency of microstrip antennas, where the precision of the resonant frequency obtained of 93.33% at an error of = 1%, and 100% at an error of = 2%.

Design and Comparative Analysis of Rectangular Slot Microstrip Patch Antennas for X-band Applications

Microstrip patch antenna is a compact antenna which suffers the limitations of poor gain and reduction in radiation pattern. To reduce the resonance frequency of microstrip antenna increases the length of surface current with help of cutting slots in the patch. In this paper, a comparison of four Microstrip antennas with unequal length of rectangular slots is proposed. The microstrip antennas having rectangular shaped ground plane and FR4-epoxy substrate with relative permittivity 4.4, relative permeability 1 and dielectric loss tangent 0.02 with an overall size of 100×100×5 mm3. The performance of antennas is compared with slots in the patch and the effects of rectangular slots using operating frequency of 8 to 12 GHz are presented. The design simulate and analyze on FEM based HFSSv11 and this helps to compute VSWR, return loss, gain, radiation efficiency and 3D polar plot of the proposed microstrip antenna. The proposed configuration gives broadside gain of more than 8 dBi and VSWR (>2) over entire range in simulated results.

Modeling resonant frequency of microstrip antenna based on neural network ensemble

AbstractResonant frequency is an important parameter in designing microstrip antenna (MSA). Selective neural network ensemble (NNE) methods based on decimal particle swarm optimization (PSO) algorithm and binary PSO algorithm are proposed in this study. The basic idea of the methods is to optimally select neural networks (NNs) to construct NNE with the aid of PSO algorithm. This may maintain the diversity of NNs and decrease the effects of collinearity and noise of sample. Simultaneously, chaos mutation is adopted to increase the diversity of particles of PSO. Experimental results show that the chaos PSO algorithm can improve the generalization ability of NNE. Moreover, by using this algorithm, model of resonant frequency of MSA is established. Computing results indicate that the model is better than the available ones. Copyright © 2010 John Wiley & Sons, Ltd.

Determining Resonant Frequencies of Various Microstrip Antennas within a Single Neural Model Trained Using Parallel Tabu Search Algorithm

Artificial neural networks (ANNs) are one of the popular intelligent techniques in solving engineering problems. In this paper, an intelligent new approach based on ANN trained with a parallel tabu search (PTS) algorithm to determine the resonant frequencies of microstrip antennas of regular geometries is presented. A single ANN model was used to determine the resonant frequencies of the rectangular, circular, and triangular microstrip antennas. The determination performance of a single neural model was improved with the help of PTS. The results obtained from the single neural model for the resonant frequencies of the rectangular, circular, and triangular microstrip antennas are in very good agreement with the experimental and other methods presented in the literature.

A numerically efficient full-wave analysis of a tunable rectangular microstrip patch

A full-wave analysis for determining the resonant frequency and half-power bandwidth of a rectangular microstrip antenna with an air gap is presented. To make the study more general and valid for various antennas structures; during the theoretical formulation the metallic patch is assumed to be embedded in a multilayered media containing isotropic and/or uniaxial anisotropic dielectrics. The proposed method for determining the Green's function leads to a concise form of this, expressed in terms of a 4 × 4 matrix multiplication, which is easily implemented. Using Galerkin's method in solving the integral equation numerically, the complex resonant frequency of the microstrip antenna with an air gap is studied with sinusoidal functions as basis functions, which show fast numerical convergence. The numerical results for Galerkin's method and experiments are in good agreement. The air gap tuning effect on the resonant frequency and half-power bandwidth is investigated. Finally, numerical results for the effects of uniaxial anisotropy in the substrate on the operating frequency of the rectangular microstrip antenna with an air gap are also presented.

Resonant frequency evaluation of microstrip antennas using a neural-fuzzy approach

The accurate evaluation of the resonant frequency of microstrip antennas is a key factor to guarantee their correct behavior. To this aim, the Method of Moments technique is currently employed. A fast technique to evaluate the resonant frequency of microstrip antennas using neuro-fuzzy networks, is proposed. Numerical results obtained by using this technique agree quite well with the Method of Moments results. The proposed technique can be fruitfully used in microwave CAD applications.

Generalized neural method to determine resonant frequencies of various microstrip antennas

A generalized method for accurate determination of the resonant frequencies of microstrip antennas of regular geometries, based on the multilayered perceptrons network, is presented. Three learning algorithms, backpropagation, delta-bar-delta, and extended delta-bar-delta are used to train perceptrons. Neural results for the resonant frequencies of the rectangular, circular and triangular microstrip antennas are in good agreement with the experimental results available in the literature. © 2002 John Wiley & Sons, Inc. Int J RF and Microwave CAE 12: 131–139, 2002.

Generalized neural method to determine resonant frequencies of various microstrip antennas

A generalized method for accurate determination of the resonant frequencies of microstrip antennas of regular geometries, based on the multilayered perceptrons network, is presented. Three learning algorithms, backpropagation, delta-bar-delta, and extended delta-bar-delta are used to train perceptrons. Neural results for the resonant frequencies of the rectangular, circular and triangular microstrip antennas are in good agreement with the experimental results available in the literature. © 2002 John Wiley & Sons, Inc. Int J RF and Microwave CAE 12: 131–139, 2002.

Resonant Behaviours of Microstrip Antenna in Multilayered Media: an Efficient Full-Wave Analysis - Abstract

This paper presents an efficient analysis of a microstrip antenna in multilayered media using the method of moments (MoM). The general forms of spectral-domain Green's functions for multilayered media are converted into the spatial-domain Green's functions using the discrete complex image method (DCIM). With the spatial-domain Green's functions, the mixed potential integral equation (MPIE) is discretized in spatial domain, and the resultant system of equations is then solved using the biconjugate gradient (BCG) method. As applications, resonant frequencies of microstrip antennas in multilayered media are analysed. The numerical results show that the present method is an efficient and accurate scheme for analysing microstrip antennas in multilayered media.

Determination of the resonant frequency of microstrip antennas

A generalized method is proposed to determine the effective dielectric constant and edge extension for predicting the resonant frequency of various microstrip antennas (MSAs) by equating their area with that of the equivalent rectangular microstrip antenna (RMSA). The theoretical frequency obtained using the present method is in very good agreement with the reported/measured frequencies. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 23: 114–117, 1999.

Simple approach to determine resonant frequencies of microstrip antennas

A simple approach for accurate determination of the resonant frequencies of microstrip antennas of regular geometries is developed and presented. In this approach, a generalised empirical formula for the computation of effective dielectric permittivity is given which takes into account the ratio of the fringing area to the area of the patch. A correction to the equivalent side length of an equilateral triangular patch, previously published, is modified and a new formula is given. A correction to the effective dimensions of an elliptical microstrip antenna is also carried out. Numerical results obtained for the resonant frequencies of elliptical, circular, rectangular and equilateral-triangular microstrip antennas are in good agreement with the available theoretical and experimental results reported by others. The present approach is more efficient, simpler and more accurate.

The method of angular line to calculate eigenvalues for microstrip antennas

The method of angular line (MAL) is presented for calculating the resonant frequency of microstrip antenna, which is available in other literature and originally used to analyze various waveguide structure. The results obtained by using this method are in conformity with those reported elsewhere.

Comments on "On the resonant frequencies of microstrip antennas"

The resonant frequencies of equilateral triangular microstrip antenna calculated by Gang (see ibid. vol.37, no.2, p.245, 1989) are compared with the experimental results of Dahele and Lee (1987). When computing the resonant frequencies of equilateral triangular microstrip antenna, using the same equations proposed by Gang, we obtained different results, which are given, from Gang's results. For an equilateral triangular microstrip antenna, the resonant frequencies obtained from the cavity model with perfect magnetic walls are given by the formula shown. In this work, we suggest a new closed-form expression. We compared our computed values of the resonant frequencies for the first five modes of the equilateral triangular patch antenna with theoretical and experimental results reported by other scientists.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Superstrate effect on the resonant frequency of microstrip antennas

AbstractA computer code based on the full‐wave analysis and the spectral domain approach was developed to predict the effect of superstates on the resonant frequency of rectangular microstrip antennas. The formulation is based on the method of moments using Galerkin technique with entire‐domain basis functions. The resonant frequency is calculated by using an optimization routine that searches for the stationary condition of the characteristic equation. Numerical solutions are obtained for some test cases and are verified by comparison with experimental results.

Theory and experiment on microstrip antennas with airgaps

In a microstrip antenna, the resonant frequency of a particular mode is determined by the shape and size of the conducting patch, the relative permittivity of the substrate and, to some extent, the thickness of the substrate. If the resonant frequency is to be changed, a new antenna is usually needed. Recently, Lee and Dahele have shown that the resonant frequencies of microstrip antennas can be changed by introducing an adjustable airgap between the substrate and the ground plane. In addition to providing a means for tuning the resonant frequencies, the airgap also has the effect of increasing the bandwidth of the antenna. The purpose of the paper is to present a comprehensive report on our research on microstrip antennas with airgaps. First, experimental results obtained by introducing an airgap in (i) circular-discs, (ii) annular-rings and (iii) dual-frequency stacked-disc microstrip antennas are presented. Secondly, the theories that have been developed are described. Thirdly, comparison between theoretical and experimental results is given.