VOL. 12, NO. 24, DECEMBER 2017 ISSN 1819-6608 ARPN Journal of Engineering and Applied Sciences ©2006-2017 Asian Research Publishing Network (ARPN). All rights reserved. www.arpnjournals.com 7297 A NOVEL NOTCHED ULTRA WIDEBAND PATCH ANTENNA FOR MOBILE MICROCELLULAR NETWORK Er-Reguig Zakaria and Ammor Hassan Electronic and Communications Laboratory, Mohammadia School of Engineers, Mohammed V University in Rabat, Morocco E-Mail: ZakariaErreguig@research.emi.ac.ma ABSTRACT In this article, we propose a radiating circular patch antenna with a partial ground plane, feed by a microstrip line, with a triangular shaped slots and one circular-ring-shaped slot in the radiating patch that can be deployed in mobile communication systems to avoid interferences with wireless local area network (WLAN) communication systems. Measured impedance bandwidth of the antenna is (0.89 GHz - 4.6 GHz), which covers GSM-900/1800/1900, UMTS 2.1 GHz (3G), UMTS 2.6 GHz (4G) and 3.5 GHz (WiMAX) for S 11 < -10 dB and also the proposed antenna have a single stop band from 2.4 GHz to 2.6 GHz for rejecting the WLAN IEEE 802.11 b/g/n frequency band. The studied antenna design, analysis and characterization has been performed using a commercially available electromagnetic solver based on finite elements. The antenna prototype was developed and realized on a FR4_epoxy substrate with a thickness of 1.58 mm, and a size of 160 x 110 mm 2 . Reflection coefficient and directivity results were measured, presented and discussed. Keywords: GSM, 3G, 4G, WiMAX, microcell, microstrip antenna, band notched, UWB. INTRODUCTION The growing needs of modern day communications mean that simple antennas cannot cover all of our needs, and further, it may cause that many systems operate across several frequency bands, the solution to this matter is to design antennas that have UWB effect and with band notch characteristics to avoid potential interference from the other frequency bands. To improve the coexistence of UWB systems with other wireless standards, a considerable amount of research has been devoted to devising techniques to reject certain bands within the passband of the UWB. The common ways to introduce the additional resonant structure include etching slots or slits on the antenna metal plate, placing parasitic strips in close proximity to the radiating element, and applying folded strips. Some UWB antennas have been reported in the literature, but most are rather large. Some researchers have focused only on the compact size of UWB. Because there is no attention paid to the band rejection in WLAN application, interference will affect the frequency range for UWB systems with the existing wireless communication systems. Some researchers presented a UWB antenna with a rejection band or band notch in the 5 GHz to 6 GHz frequency range by using an insertion strip or slot in the antenna. A reported UWB antenna was designed by embedding a U-shaped parasitic strip and a pair of T- shaped stubs in wide slots to obtain dual-band stops around 3.5 GHz and 5.5 GHz. An UWB antenna has been designed with a dual band-notch for WLAN that covers the frequency ranges of 5.09 GHz to 5.36 GHz and 5.72 GHz to 5.825 GHz. Also the authors presented a novel dual band-notched monopole antenna at 3.5 GHz (WiMAX) and 5.5 GHz (WLAN); however, the results do not show the shifted band-notched frequency with enhanced Bandwidth (BW) of the band notch. Moreover, the geometry of this antenna is relatively complex. In this research paper, we propose a circular slot microcell antenna with a partial ground plane for UWB applications. By inserting a simple parasitic insertion strip (two types: ring-shaped and triangular-shaped), single band-notched characteristics from 2.44 GHz to 2.66 GHz can be easily obtained to reduce the potential interference between the UWB system and Indoor communication like the WLAN (Wi-Fi) systems. ANTENNA DESIGN Figure 1 illustrates the schematic of the proposed antenna. The basic antenna (antenna a) is a circular patch which was the subject of a number of changes to cut the frequency band 2.4 GHz reserved for the Wi-Fi/WLAN systems. The proposed antenna (antenna c) consists of a circular radiating patch with slots and a partial ground plane is printed on the bottom surface of the substrate. Figure-1. Schematic of the proposed antenna.