1.Title: STUDY OF A CLASS OF A UWB CPW –FED MONOPOLE ANTENNA WITH FRACTAL ELEMENTS
In this paper studied about the Ultra Wide Band (UWB)coplanar waveguide(CPW) monopole –fed antenna. The technique used in this Multiresonance. Different shapes are added to antenna to observe the multiresonance which enhance the Impedance bandwidth. In this FIDELITY factor is greater than 0.92 .Time domain performance of the antenna is done and verified by using fidelity factor. In this the feed structure used is cpw and hexagonal radiator is used. It is observed that impedance characteristics is improved from 3-7Ghz .Band width of upper frequency is shifted to 8.8-10.9 Ghz.
AN H-FRACTAL ANTENNA FOR MULTIBAND APPLICATIONS
This antenna excites multiple resonances and also shows good reflection coefficients and radiation properties. This antenna is simple and straight forward to design. Multiband is achieved by using this antenna which is the main proposed feature. The dominant resonance frequency is 0.36GHz at this frequency the resistance is very small 2.7ohms resulting a mismatch at 50 ohms this problem can be solved by using impedance transformation to obtain impedance match. variation of the resonant frequencies, simulated reflection coefficients S11 of the H-fractal antenna in different stages are looked over. This proposed H-fractal antenna is good working at 5.5GHz for WLAN band. The PSO
method has been applied to optimize the proposed H-fractal
for 2.45/5.5-GHz WLAN application.
3.TITLE: Dual-Band Antenna With Fractal-Based Ground Plane for WLAN Applications
In this paper studied about Dual band antenna with fractal based ground plane for WLAN applications. In this the ground plane is in fractal shape is used in order to improve the performance of solid ground plane and obtained the multiband behavior.. This multi band antenna is based on a equilateral triangular monopole .Fractal based ground plane has a good impedance match 50ohms at 2.4Ghz ,moreover
5.4GHz band has improved .Its radiation efficiency is over 90% .Radiation patterns are similar in both bands and directivity and efficiency have not been significantly changed by the use of the fractal-based ground plane with respect to a solid ground plane of the same size.
4.TITLE: Perturbed Sierpinski Carpet Antenna With CPW Feed for IEEE 802.11 a/b WLAN Application
In this paper studied about perturbed sierpinski carpet antenna with CPW feed for IEEE 802.11a/b WLAN applications. This antenna adopts modified sierpinski carpet geometry in planar monopole configuration. Return loss characteristics suggests that it is also used for Hiper LAN2 system. This antenna gain is around 3.2 dbi at lower band and 4.5 dbi at higher band. The radiation characteristics of proposed antenna suggest vertical mounting. The proposed antenna is analyzed using IE3D and verified using CST Microwave Studio (CST MWS). The return loss
of the fabricated prototype is measured using a HP8722C VNA.