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In this paper, a miniaturized elevated-coplanar-waveguide-fed antenna with a slotted ground plane is proposed. This antenna has a compact size of 25 mm × 25 mm × 1.6 mm where the ground plane is reduced by etching a trapezoidal slot along with two extended slits. A −10 dB wide-impedance bandwidth of 126% ranging from 2.8 to 12.4 GHz is achieved for the proposed antenna. The proposed antenna is successfully manufactured and experimentally investigated. The measurement shows a good agreement with the simulation. The measured radiation characteristic shows a stable and nearly omnidirectional pattern over the operating bandwidth region. The effects of various parameters on the antenna performance are analyzed and discussed as well.

A generalized method is presented to determine the resonant frequency of slot-loaded rectangular microstrip patch antenna by equating its area to an equivalent area of a rectangular microstrip patch antenna. The computed results are in good agreement with the reported simulated and measured results. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 445–448, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24901

A compact printed microstrip line-fed wideband antenna is presented for WLAN, WIMAX and various applications. This antenna has a compact size of 30 × 30 × 1.6 mm3 and the ground plane size is reduced by introducing a rotating slot. A square patch is embedded as a parasitic element at the center of the rotating slot to increase the impedance bandwidth. Rectangular slots are cut in the square patch to compensate the return loss. A pair of E-shaped parasitic patches along the 50 ohm microstrip line is used to introduce additional resonance excitation which can enhance the bandwidth. The proposed antenna is successfully manufactured and experimentally investigated. The measured results are in good agreement with the simulation results. The impedance bandwidth is found to be 74.4% ranging from 2.45 GHz to 5.35 GHz. The measured radiation pattern is found to be stable and nearly omnidirectional throughout the operating bandwidth region.

This paper deals with the design of a multi-slot hole-coupled microstrip antenna on a substrate of 2 mm thickness that gives multi-frequency (wideband) characteristics. The Method of Moments (MoM)-based IE3D software was used to simulate the results for return loss, VSWR, the Smith chart, and the radiation patterns. A tunnel-based artificial neural network (ANN) was also developed to calculate the radiation patterns of the antenna. The radiation patterns were measured experimentally at 10.5 GHz and 12 GHz. The experimental results were in good agreement with the simulated results from IE3D and those of the artificial neural network. A new method of using a genetic algorithm (GA) in an artificial neural network is also discussed. This new method was used to calculate the resonant frequency of a single-shorting-post microstrip antenna. The resonant frequency calculated using the genetic-algorithm-coupled artificial neural network was compared with the analytical and experimental results. The results obtained were in very good agreement with the experimental results.

In this paper, a clonal selection algorithm based method is presented for the optimization of slot parameters embedded on ultra-wideband antennas to notch-out frequency bands to prevent interference between ultra wideband (UWB) systems and existing wireless systems. The method is applicable for both half-wavelength and quarter-wavelength slot-resonators. The effects of substrate properties are included in the proposed work. The method is validated by comparing the computed values with experimental values reported earlier. It shows very good agreement.

A parasitic-coupled T-shaped microstrip patch antenna is discussed in this article. The T-shaped microstrip patch antenna gives dual band resonant frequency on a thin substrate. The two resonant frequencies are within the 3 dB bandwidth that shows wide bandwidth. The experimental result is in good agreement with the calculated result. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1339–1341, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23363

The resonance frequency of an E-shaped microstrip antenna has been calculated by equating its area to an equivalent area of a rectangular microstrip patch antenna. A new expression for effective dielectric constant is developed for the E-shaped microstrip patch antenna. The new expression of resonance frequency is used to calculate the results, which are in good agreement with the measured and published results. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1561–1563, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21700

A printed quad band microstrip antenna is presented in this paper. The proposed microstrip-fed antenna consists of a circular ring connected to a slotted square with two arc shaped arms operates in the 1990 MHz Personal Communication System(PCS) band, 3.5/5.5 GHz worldwide interoperability for microwave access (WiMAX) bands, 6–7 GHz Satellite communication bands. The antenna has dimensions of 38×25×1.59 mm3. The proposed antenna is simulated with HFSS software and achieved good impedance bandwidth, directional radiation pattern and improved peak gain in the all four operating frequency bands.

Both genetic algorithms (GAs) and artificial neural networks (ANNs) have been used in the field of computational electromagnetics as the most powerful optimizing tools. In this paper, a simple and efficient method is presented to handle the problem of competing convention while training an ANN by using a GA. This technique is applied to calculate the resonant frequency of a thick-substrate rectangular microstrip antenna (RMA). The training time is less than that of a normal feed-forward backpropagation algorithm. The measured results are in very good agreement with experimental results. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 41: 313–315, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20126

Coax-fed inverted L-shaped microstrip antennas and parasitically coupled inverted L-microstrip antennas are presented. The inverted L-shaped microstrip antenna gives an impedance bandwidth of 30.6%, which is increased to 33.7% by parasitic coupling. The bandwidth has been achieved with a substrate thickness of 2 mm. Radiation patterns and gains are also studied and presented. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 190–192, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20248

Over the years, genetic algorithms (GAs) have been applied in many applications. But the lack of a proper fitness function has been a hindrance to its widespread application in many cases. In this paper, a novel techniqueof using artificial neural networks (ANNs) as the fitness function of a genetic algorithm in order to calculate the design parameters of a thick substrate rectangular microstrip antenna is presented. A multilayer feed-forward neural network is used as the fitness function in a binary-coded genetic algorithm. The results obtained using this method are found to be closer to the experimental value, as compared to previous results obtained using the curve-fitting method. To validate this, the results are compared with the experimental values for five fabricated antennas. The results are in very good agreement with the experimental findings.

In this paper, the genetic algorithm (GA) has been applied to calculate the optimized length and width of rectangular microstrip antennas. The inputs to the problem are the desired resonant frequency, dielectric constant, and thickness of the substrate; the outputs are the optimized length and width. The antennas considered are electrically thin. Method of moments (MoM)-based IE3D software from Zealand Inc., USA, and experimental results are used to validate the GA-based code. The results are in good agreement. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 37: 431–433, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10940

A new method for calculation of band width with optimized length and width of rectangular microstrip antenna using Clonal selection algorithm (CSA) is presented in this paper. The result obtained using CSA are compared with the experimental findings and with the simulation results obtained using method of moment based IE3D software from Zealand Inc., USA. The CSA based calculated results are in good agreement.

A novel method of optimization by coupling the genetic algorithm (GA) and artificial neural network (ANN) is presented in this paper. A trained artificial neural network is taken as objective function in GA for optimization. By utilizing this technique the optimized dimensions of patch antenna on thick substrate has been calculated. It is seen that the results obtained by this method are closer to experimental value compared to earlier results obtained by curve fitting method. To validate this, the results are compared with experimental values for five fabricated antenna. The results are in very good agreement with experimental findings.