Available online at www.sciencedirect.com Procedia Technology (2012) 778 – 783 2nd International Conference on Communication, Computing & Security [ICCCS-2012] An Ultra-wideband Printed Monopole Antenna with Dual BandNotched Characteristics Using DGS and SRR M M Sharmaa, Ashok Kumarb, Sanjeev Yadavb, Y Rangac * a Govt Engineering College, Ajmer,305002, India Department of Electronics and Communication Engineering, Govt Women Engineering College, Ajmer,305002, India c Department of Electronic Engineering, Macquarie University, NSW, 2109, Australia b Abstract An ultra-wideband printed monopole antenna with dual band-notched characteristics is presented The antenna consists of a split ring resonator (SRR) on the circular patch and defected ground structure (DGS) and symmetrical-slits in the coplanar ground plane It is designed for avoiding interference with Worldwide Interoperability for Microwave Access (Wi-Max) (3.4 3.69 GHz) and Wireless Local Area Networks (WLAN) (5.15 5.825 GHz) Predicted impedance bandwidth of antenna is 2.70 10.67 GHz, for VSWR < Incorporation of DGS and SRR results in dual band-notched bandwidth from 3.30 GHz 3.86 GHz and 5.28 5.89 GHz respectively The gain of antenna varies 2.48 dBi to 4.72 dBi over the operating bandwidth In the band notched regions, the gain reduces from its normal value to about 7.94 dBi at 3.64 GHz while it reduces by 4.27 dBi at 5.67 GHz © 2012 2012Elsevier The Authors Publishedand/or by Elsevier Ltd under responsibility of the Department of Computer Science & © Ltd Selection peer-review Selection and/or peer-review under responsibility of the Department of Computer Science & Engineering, National Institute Engineering, National Institute of Technology Rourkela of Technology Rourkela Keywords:Band-Notched; Defected ground structure; Split ring resonator; Ultra-wideband; WLAN; WiMAX Introduction In recent years, ultra-wideband systems have been required for many applications, because of its inherent features like small size, high data transmission with short-range, larger bandwidth, simple hardware configurations, low power consumption, omnidirectional radiation pattern and a linear phase response UWB is * M.M Sharma Tel.: +91-9413346999 E-mail address: mmsjpr@gmail.com 2212-0173 © 2012 Elsevier Ltd Selection and/or peer-review under responsibility of the Department of Computer Science & Engineering, National Institute of Technology Rourkela doi:10.1016/j.protcy.2012.10.094 M M Sharma et al / Procedia Technology (2012) 778 – 783 a high data rate and short range wireless technology, utilizing the unlicensed radio spectrum from 3.1 to 10.6 GHz, which is allocated by the Federal Communication Commission (FCC) in the year of 2002 [1 4], around this enormous bandwidth there are several narrow band systems pre exists and UWB communication potentially cause interference to the narrow band systems The mostly commonly used narrow band systems affected by UWB systems are WiMAX band (3.4 3.69 GHz), IEEE 802.11a wireless local area network bands (5.15 5.35 GHz and 5.725- 5.825 GHz) and HIPERLAN/2 band (5.450 5.725 GHz) To avoid interference between UWB and these systems, UWB antennas with frequency notched function is highly desirable and various design schemes has been reported recently [5 11] The most common methods to achieve bandnotched characteristics in printed monopole antennas are cutting the slots on the feed line, on the ground plane or on the patch The band notched behavior in printed monopole antennas may be achieved by cutting the Ushaped slot [5], by cutting semi-elliptical slot in the patch [6], by cutting the axis symmetrical elliptical slots in the patch [7], by cutting a fractal shaped slot [8] Another way is to put parasitic elements near the patch to achieve band notched characteristics [9, 10] These designs have the limitation of feed line width, which depends on the 50 input impedance line The new way to achieve a band notched characteristics is by inserting the split ring resonators (SRRs) or complementary split ring resonators (CSSRs) in the patch [11 14] and DGS in the ground plane [15] has been reported In this paper, UWB printed monopole antenna with dual band-notched characteristics is proposed The dual band notched characteristics are obtained by etching symmetrical slits in the coplanar ground plane or DGS and split ring resonator on the circular patch The CST Microwave Studio [16] is used to predict the performance of this antenna Fig Geometry of UWB printed monopole antenna with DGS and SRR; Antenna Design Fig.1 shows the geometry of the proposed UWB printed monopole antenna with DGS and SRR The = 1.6 mm, relative antenna is printed on the glass epoxy FR-4 dielectric substrate with thickness permittivity r = 4.4 with a loss tangent = 0.02 A circular patch with a radius is printed on the top 779 780 M M Sharma et al / Procedia Technology (2012) 778 – 783 side of the glass epoxy FR-4 dielectric substrate, a CPW feed line along with the coplanar ground plane is printed on the same side of the substrate To achieve 50 ohm characteristic impedance a width and gap is provided between the CPW feed line and the coplanar ground plane The outer and inner radiuses of the split ring are denoted with and , respectively This split ring is etched in the circular patch to achieve the band-notched operation in the WLAN band The symmetrical slits are etched in the coplanar ground plane to achieve the strong band-notch operation in the WiMAX band The overall dimension of this antenna is L × W mm2 There is gap of between the circular patch and the ground plane A sub-miniaturized (SMA) type A connector is connected to the CPW feed line The simulation of structure was carried out in CST Microwave Studio The final optimized parameters of the proposed antenna shown in Fig are L = 40 mm, L1 = 12.6 mm, L2 = 1.2 mm, L3 = mm, W = 34 mm, W1 = 2.9 mm, W2 = 15.2 mm, W3 = 9.5 mm, W4 = 11.7 mm, W5 = 3.2 mm, R = 10 mm, r1 = 3.4 mm, r2 = 2.1 mm, h = 0.6 mm, g = 0.35 mm, g1 = 1.2 mm and g2 = 0.3 mm The proposed antenna consists of the two parts: circular patch with SRR and two symmetrical slits in the coplanar ground plane or defected ground structure (DGS) prevent the interference with WLAN and WiMAX bands, respectively According to small size of the single split ring resonator (SRR) and its signal rejection performance, it is etched in the circular patch of the UWB printed monopole antenna to achieve a band notched characteristics in the WLAN band, because the split ring resonator behaves as a quasi-static resonance circuit which provides the distributed capacitance between concentric rings and rings overall inductance The split ring resonator is placed close to the coplanar feed line By insertion of the symmetrical slits in the coplanar ground plane provides strong signal rejection performance in the WiMAX band Results and Discussion 3.1 Impedance bandwidth and VSWR results The simulation results of an ultra-wideband printed monopole antenna with dual band-notched characteristics using DGS and SRR are presented The performance of the proposed antenna is compared with that of a CPW-fed circular disc monopole antenna [4] considered as a reference antenna Fig 2(a) Fig 2(b) shows the simulated |S11| parameter and VSWR curve as the function of frequency, respectively The theoretically achieved impedance bandwidth of this antenna is 2.70 10.67 GHz, for VSWR < With the insertion of DGS and SRR, dual band-notched characteristics from 3.30 GHz 3.86 GHz and 5.28 5.89 GHz are achieved, for VSWR > 2, covering WiMAX and WLAN bands, respectively Therefore, the interference between UWB and narrow band systems are eliminated 3.2 Gain and radiation pattern results Fig 2(c) shows the simulated gain curve as the function of frequency The gain variation of this antenna in operating bandwidth is from 2.48 dBi to 4.72 dBi, which is large over the entire frequency range The gain variation over the operating bandwidth of this design is less than dBi Significantly gain reduction over the rejected bands as shown in Fig 2(c) In the dual band-notched regions, the gain reduction is about 7.94 dBi at 3.64 GHz and 4.27 dBi at 5.67 GHz Fig shows the E- plane and H- plane radiation patterns of an ultra-wideband printed monopole antenna with dual band-notched characteristics at GHz, 3.64 GHz, GHz, and 10 GHz frequencies, respectively It is seen that in the E-plane typical figure of eight shaped radiation patterns at lower frequencies and the higher frequency the number of lobes increases and the value of cross polarization increases The H-plane shows nearly omnidirectional radiation patterns over the entire frequency range It is also observed the radiation pattern at central notched frequencies are significantly changes because of the increasing the current distribution near the split ring resonator and symmetrical slits in the coplanar ground plane M M Sharma et al / Procedia Technology (2012) 778 – 783 Fig (a) Simulated S11 parameters of the proposed antenna and reference antenna [4]; (b) Simulated VSWR values of the proposed antenna and reference antenna [4]; (c) Simulated gains of the proposed antenna and reference antenna [4]; Conclusions An ultra-wideband printed monopole antenna with dual band notched characteristics is presented The dual band notched characteristics are obtained by etching the symmetrical slits in the coplanar ground plane and the split ring resonator on the circular patch The simulated results indicate the proposed antenna yields ultrawide bandwidth with dual band notched characteristics for WiMAX and WLAN bands The H-plane radiation patterns show nearly omnidirectional radiation pattern over the entire frequency range The antenna gain is reduced in the dual band-notched region Thus the proposed antenna is suitable for UWB system while providing isolation to other communication bands 781 782 M M Sharma et al / Procedia Technology (2012) 778 – 783 Fig Simulated E-plane (left side) and H-plane (right side) radiation patterns of the proposed antenna at (a) GHz; (b) 3.64 GHz; (c) GHz; (d) 10 GHz References [1] New Public Safety Applications and Broadband Internet Access among Uses Envisioned by FCC Authorization of Ultra-Wideband Technology-FCC News Release 2002 [2] H G Schantz, G Wolenec, and E M Myszka III, Frequency notched UWB antennas, Proc IEEE Conferences Ultra Wideband System Technology, Nov 2003; pp 214-218 [3] X Shen, M Guizani, R.C Qiu and T Le-Ngoc, Ultra-Wideband Wireless Communication and Networks, John Wiley & Sons, England, 2006 [4] J Liang, L Guo, C C Chiau, X Chen and C G Parini, Study of CPW-fed circular disc monopole antenna for ultra wideband applications, IEE Proc.-Microw Antennas Propag., Dec 2005; 152( 6): pp 520-526 [5] S W Su, K L Wong and F S Chang, Compact printed band-notched ultra-wideband slot antenna, IEEE International Symposium on Antennas and Propagation Society, 2005; vol 2B: pp 572-575 [6] M Gopikrishna, D D Krishna, and C K Aanandan, Band-notched semi-elliptic slot antenna for UWB systems, Proceedings of the 38th European Microwave Conference, Amsterdam, 2008; pp 889-892 [7] M M Sharma, Ashok Kumar, Y Ranga and D Bhatnagar, An ultra-wideband antenna with axis symmetrical elliptical slots for tunable band-notched characteristics, IEEE Asia Pacific Microwave Conference, 2011; pp 725-728 [8] W J Liu, C H Cheng, and H B Zhu, Compact frequency notched ultra-wideband fractal printed slot antenna, IEEE Microwave Wireless Component Letters, April 2006; 16(4): pp 224-226 [9] K Zhang, Y Li, and Y Long, Band-notched UWB printed monopole antenna with a novel segmented circular patch, IEEE Antennas and Wireless Propagation Letters, 2010; vol 9: pp 1209-1212 [10] K H Kim, Y J Cho, S H Hwang, and S O Park, Band-notched UWB planar monopole antenna with two parasitic patches, Electronics Letters, July 2005; 41(14): pp 783 785 M M Sharma et al / Procedia Technology (2012) 778 – 783 [11] J Kim, C.S Cho, and J.W Lee, 5.2 GHz notched ultra-wideband antenna using slot-type SRR, Electronics Letters, March 2006; 42(6): pp 315-316 [12] W J Lui, C H Cheng and H B Zhu, Improved frequency notched ultrawideband slot antenna using square ring resonator, IEEE Transactions on Antennas and Propagation, September 2007; 55(9), pp 2445-2450 [13] J Liu, S Gong, Y Xu, X Zhang, C Feng and N Qi, Compact printed ultra-wideband monopole antenna with dual band-notched characteristics, Electronics Letters, June 2008; 44(12), pp 710-711 [14] M C Tang, S Xiao, T Deng, D Wang, J Guan, B Wang and G D Ge, Compact UWB antenna with multiple band-notches for WiMAX and WLAN band, IEEE Transactions on Antennas and Propagation, April 2011; 59(4), pp 1372-1376 [15] S Soltani, M Azarmanesh, P Lotfi and G Dadashzadeh, Two novel very small monopole antennas having frequency band notch function using DGS for UWB application, International Journal of Electronics and Communications, 2011; 65, pp 87-94 [16] www.cst.com 783 ... performance in the WiMAX band Results and Discussion 3.1 Impedance bandwidth and VSWR results The simulation results of an ultra- wideband printed monopole antenna with dual band- notched characteristics. .. proposed antenna and reference antenna [4]; (c) Simulated gains of the proposed antenna and reference antenna [4]; Conclusions An ultra- wideband printed monopole antenna with dual band notched characteristics. .. GHz and 4.27 dBi at 5.67 GHz Fig shows the E- plane and H- plane radiation patterns of an ultra- wideband printed monopole antenna with dual band- notched characteristics at GHz, 3.64 GHz, GHz, and