Planar UWB Antenna with Double Band Rejection Capability Using Double Inclined ESRRs Ghidaa T. Ahmed 1* , Ahmed S. Elkorany 1** , and Demyana A. Saleeb 2*** 1 Menoufia University, Al Minufya, Egypt 2 Kafrelsheikh University, Kafr Elsheikh, Egypt *e-mail: eng_ghidaa@yahoo.com **ORCID: 0000-0003-3400-2971 , e-mail: elkoranyahmed@yahoo.com ***ORCID: 0000-0001-5761-0078 , e-mail: d_saleeb@theiet.org Received August 14, 2017 Revised April 23, 2018 Accepted December 18, 2018 Abstract—This paper deals with elliptical split ring resonator (ESRR) loaded CPW-fed ultra wideband (UWB) printed monopole antenna (PMA) with dual band-notching at 5.2 and 6.9 GHz to notch WLAN and C-band wireless applications, respectively. The antenna is fabricated on duroid dielectric substrate with thickness of 1.6 mm and e r = 2.2. The antenna uses two ESRR with different dimensions to create dual band-notched characteristics. Details of the proposed antenna are presented along with simulated results. The effect of ESRR dimensions and position is examined. The ESRR is also rotated and the effect of this rotation in the notch frequency is also examined. Radiation patterns are simulated by HFSS and omnidirectional radiation patterns in the H-plane could be observed. The group delay is nearly stable in the UWB frequency range, except at the notch frequencies, which is distorted sharply. So, the proposed antenna is a good candidate for the modern UWB systems. Finite element method (FEM) and finite integration technique (FIT) are used to simulate the proposed structures through the usage of HFSS and CST. A very good agreement between both results has been obtained. DOI: 10.3103/S0735272719030038 1. INTRODUCTION A leap in scientific research has occurred since February 2002, when the FCC decree that UWB could be used for data communications as well as for radar and safety applications [1]. The Federal Communications Commission (FCC) first defined UWB as any system having a bandwidth of at least 500 MHz or a fractional bandwidth larger than 0.20. Higher data rates, low power consumption large band width, etc. are some of the reasons why ultra-wideband has attracted all the attention over the past years [2]. By comparing ultra-wideband (UWB) system with conventional or narrowband systems, a large bandwidth is used to transmit data. The power used over the whole band is much lower than the power used by narrowband systems [3]. In 2002 the FCC allowed the frequency band between 3.1 and 10.6 GHz for unlicensed UWB transmission. The effective isotropic radiated power (EIRP) should be below –41.3 dBm inside the frequency band. UWB provides high secure and high reliable communication solutions due to the low energy density. UWB system has features of low cost and low complexity as it based on baseband signal transmission. UWB does not need modulation and demodulation, so it does not require components such as local oscillators, amplifiers, filters, and mixers. The antennas are an essential part of any wireless system. Antennas fabricated on planar substrates have been of increased demands it yields very large bandwidth so it can be easily integrated with the microwave integrated circuit (MIC) used in high frequency applications [4–7]. Using this technology, antennas can be of reduced size and easily manufactured. Sometimes, it is also demanded UWB antenna with frequency notch characteristics need to be designed to suppress radiation to obviate interference of UWB system with the other narrow-band devices and services occupying the same operational band like WLAN, WiMAX, C-, and X-band wireless systems [8, 9]. These bands could be rejected with band stop filters in UWB, but this approach will increase the 119 ISSN 0735-2727, Radioelectronics and Communications Systems, 2019, Vol. 62, No. 3, pp. 119–126. © Allerton Press, Inc., 2019. Russian Text © G.T. Ahmed, A.S. Elkorany, D.A. Saleeb, 2019, published in Izvestiya Vysshikh Uchebnykh Zavedenii, Radioelektronika, 2019, Vol. 62, No. 3, pp. 147–157.