This paper proposes a possible implementation of a compact printed monopole antenna, useful to operate in UMTS and WLAN bands. In order to accomplish that, a miniaturization technique based on the application of chip inductors is used in conjunction with frequency reconfiguration capability. The chip inductors change the impedance response of the monopole, allowing to reduce the resonant frequency. In order to be able to operate the antenna in these two different frequencies, an antenna reconfiguration technique based on PIN diodes is applied. This procedure allows the change of the active form of the antenna leading to a shift in the resonant frequency. The prototype measurements show good agreement with the simulation results.

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Compact, Frequency Reconfigurable, Printed Monopole Antenna

This paper presents a multi-fractal antenna operating in ultra wide band range for WLAN and WiMAX applications. The novel idea of multi-fractal geometry is introduced into the conventional triangular patch antenna with microstrip feed. The addition of Koch and Sierpinski fractal techniques gives rise to better impedance bandwidth and return loss characteristics. The proposed antenna exhibits resonant frequency at 5.48 GHz with a return loss of -31.9dB to satisfy the band specifications for wireless LAN applications IEEE802.11a (5.15-5.35 GHz, 5.725-5.875 GHz) and WiMAX application at 5GHz (5.25-5.85 GHz). It is found that the antenna exhibits omni-directional radiation pattern in H plane with a maximum gain of 3.5dB. The antenna exhibits a stable radiation pattern throughout the operating frequency range of 4.68-6.43 GHz. The antenna covers the upper and lower bands of WLAN operating frequencies. The simulation was performed in High Frequency Structure Simulator.

A multi-fractal antenna for WLAN and WiMAX application

This paper presents a Koch-like sided Sierpinski multi-fractal antenna for ultra wide band applications. The fractal techniques such as the Koch and Sierpinski Fractal techniques are been introduced into the conventional triangular patch antenna with microstrip feed to obtain better return loss and impedance bandwidth characteristics. The simulation was performed in High Frequency Structure Simulator (HFSS 13). The antenna parameters such as resonant frequency, return loss, radiation pattern and surface current distribution are simulated and discussed in this paper.

Design and analysis of a multi-fractal antenna for UWB application

Wddeband application put a new demand on antennas pertaining to size, gain, efficiency, bandwidth and more. This paper presents the design and analysis of fractal antenna which uses the self similarity property of fractal geometry. This unique property is exploited to develop antenna elements that are wideband and compact possessing highly desirable properties. The presented antenna is circle inscribed octagon shaped. Simulation results show that the antenna can be used in different frequency ranges exhibiting wideband properties. Radiation pattern and gain characteristics are also analysed.

Wideband fractal microstrip antenna for wireless application

In this paper a novel design for miniaturization of patch antenna is presented. The proposed design for the miniaturized wide band patch antenna consists of hybrid techniques of H-shaped slot on the patch and defected ground structure. Defected ground structure is formed by cutting a combination of U and L-shaped slots. Patch and the ground plane are shorted for the further size reduction. These practices increase the current distribution path accompanied by increase in electrical length of the antenna. To validate the design a reference patch antenna is designed and its performance is compared with the proposed antenna. The designed antenna is 86% smaller than the conventional patch antenna. The miniaturized antenna has gain in the range of 4dBi to 5dBi while impedance bandwidth is in the range of 105MHz to 1700MHz. This form of compact wide band antenna is appropriate for numerous wireless communication systems like cell phone, Laptop and Hyperlane.

Compact multiband microstrip patch antenna using defected ground structure (DGS)

This paper presents the design and analysis of fractal antenna that contributes ultra wide band characteristics. Fractal technique is adopted to improve radiation characteristics of the antenna. The impedance bandwidth of the proposed fractal antenna is 9.4 GHz ranging from 3.2GHz to 12.6 GHz with maximum gain of 6.2dB and efficiency of 98.66%. Analysis of antenna is done using CST Microwave Studio.

Design and analysis of fractal antenna for UWB applications

In this paper fractal technique is analysed for antenna miniaturization. The space filling property of fractals is used for size reduction of patch antenna. By the application of fractal technique, the effective electrical length of the antenna is increased for the same resonant frequency. However, the fractal antenna has the same radiation pattern and input impedance as a conventional antenna. In our work, we use the Koch fractal for size reduction of circular patch antenna. 45% reduction in operating frequency and 21% reduction in size has been achieved in proposed design. Analysis of antenna is done in CST Microwave Studio.

Ayachi Ajey

Papers

Design and analysis of fractal antenna for UWB applications

Size miniaturized fractal antenna for 2.5GHz application