The effect of slot on patch and on ground plane of rectangular microstrip antenna for effective size reduction, wide bandwidth, and high gain has been presented. A 60.57% of virtual size reduction is achieved by taking ground plane same as that of patch on another similar substrate and by keeping 1-mm air gap between them. Furthermore, 51% of bandwidth and 8.73 dB of gain are achieved by embedding group of slots on the patch, wide slot on the ground plane and by doubling the thickness of substrate.

Abstract-This paper reports the design and development of rectangular microstrip antenna comprising a novel slot for enhancing the impedance bandwidth and gain. By incorporating a slot of optimum geometry at suitable location on the radiating patch, the antenna provides 78.08% (3.39-7.73 GHz) of impedance bandwidth and 3 dB of gain without changing the nature of broadside radiation characteristics when compared to conventional rectangular microstrip antenna. The proposed antenna may find applications in mobile WiMax, IEEE802.11a, HIPERLAN/2, cordless phones, fixed wireless etc. Design concept of antennas is given, and experimental results are discussed.

A novel design of square microstrip antenna is designed for dual band operation. By embedding unequal length inverted right angle slot at optimum place on the square patch, the upper operating band enhanced from 27.53 to 60.01% with minimum change in the lower operating band retaining the nature of broad side radiation characteristics. The proposed antennas may find application in radar communication. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2578–2582, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24678

In this letter, a novel method that can achieve critical coupling of a PIFA is proposed. The proposed antenna can accomplish critical coupling by attaching a ferrite sheet without changes to the structure of the antenna. A ferrite sheet is used to increase the shunt inductance of the shorting pin loop. An equivalent circuit based on transmission line modeling was used for designing the ferrite-sheet-loaded PIFA, and it was verified that critical coupling was accomplished based on a Smith chart produced by a 3D EM simulator. The proposed PIFA has a very wide bandwidth of 16% for VSWR < 2, and a good omni-directional radiation pattern at its operating frequency. ACKNOWLEDGMENTSABSTRACT: This article presents a novel design of complementarysymmetry aperture-coupled microstrip antenna for wideband, adequate gain, and low cross-polarization. An experimental bandwidth of 129.51% with gain of 5.17 dB is achieved. The antenna operates from 3.85 to 18 GHz, which covers C, X, and Ku bands. The obtained crosspolar power level is À30.5 dB down with respect to co-polar. The effect of coupling aperture and microstrip feedline is studied and reported.

image. We will report the excitation of the surface plasmon polaritons on the surface of the fabricated metamaterial in the future.ABSTRACT: A novel complementary-symmetry microstrip array antenna is presented for broadband operation. The maximum impedance bandwidth of 132.12% and high gain of 10.08 dB is achieved. The radiation patterns are found broadsided across the entire operating band. The design concept of the antenna is described and the experimental results are discussed. The proposed antenna may find applications for the systems operating from C to Ku (3.9 to 18 GHz) band of frequencies.