IJSRD - International Journal for Scientific Research & Development| Vol. 4, Issue 05, 2016 | ISSN (online): 2321-0613
Dual Band Microstrip Antenna for X-Band Applications Chandravir Singh1 Sudhanshu Mathur2 1 M.Tech. Scholar 2Assistant Professor 1,2 Department of Electronics & Communication Engineering 1,2 Jagannath University, Jaipur, India-303901 Abstract— A Rectangular Microstrip patch antenna is designed here for wireless communication systems. The antenna is designed on Rogers RT5880 substrate having Є=2.2 and characterized by measuring return loss, gain and radiation pattern. The proposed antenna has low profile, light weight and has successfully demonstrated multiband characteristics which covers WIMAX, WLAN, Bluetooth, Xband and other wireless applications. For designing and simulation of proposed antenna we have used CST Microwave Studio Suite software. Key words: CST-Computer Simulation Technology, WLAN-Wireless Local Area Network, MSA-Microstrip Antenna
Microwave Studio software. The design of proposed antenna is shown below in Fig. 1.
I. INTRODUCTION
III. SIMULATION RESULTS
Antenna plays an important role in wireless communications. For point to point wireless communication and Wi-Fi the antenna should be compact and efficient for convenience. Design of compact multi-band antennas for state-of-art wireless applications like smart-phones and WiFi enabled laptops is one of the challenging problems for microwave engineers. Microstrip antennas are attractive due to their light weight, conformability and low cost. A major contributing factor for recent advances of Microstrip antennas is the current revolution in electronic circuit miniaturization brought about by developments in large scale integration. Microstrip patch antennas are good choice for this purpose due to their low-profile and compatibility with planar monolithic microwave integrated circuit (MMIC) components. However, they suffer from disadvantages like poor scan performance, narrow bandwidth etc. [1].
CST Microwave Studio software provides a variety of solvers for simulations. For our design, we have chosen time-domain solver which is suitable for planar antenna applications. Input matching with respect to 50 Ω was carried out and the antenna radiation pattern. Return loss curve gives information about operating frequency. The return loss curve for our antenna is shown in Fig. 2.
II. METHODOLOGY The proposed antenna is designed on Rogers RT 5880 substrate having Є=2.2 and is of square geometry. The thickness of substrate is chosen as 1.6mm. However, the patch is of rectangular geometry and has dimensions of length and width is taken as 9.78mm and 12.6mm respectively. Both the patch and the ground plane are made up of perfect electric conductor (PEC). The values of all the parameters taken are tabularised in Table 1 below. Parameter Value [mm] L 21.169 Lp 9.78 Offset 1.5 Radius 0.4 t 1.5 W 12.6 Table 1: Design Parameters The antenna is fed by coaxial feeding technique. The reference impedance is comes out to be 54Ω. These values lead antenna to have operating frequency in X-band. The design and modelling of antenna is carried out in CST
Fig. 1: Proposed antenna Design
Fig. 2: Return Loss From above figure, it is clear that we have designed a dual-band antenna operating at frequencies viz. 9.34GHz and 14.88GHz respectively. The return loss at 9.34GHz frequency is -17.28dB and at 14.88GHz is -18.12dB. The VSWR calculated by simulation result is 1.31for 9.34GHz and 1.28 for 14.88GHz frequency. VSWR values consistently stay below 2 within the frequency band of 9.34 GHz to 14.88 GHz thereby showing stable radiation pattern. Moreover from the return loss plot a wide bandwidth of 5.54 GHz is obtained between 9.34 GHz and 14.88 GHz. However, the polar plot for designed antenna at 9.32GHz is shown in Fig. 3 below.
Fig. 3: Polar Plot at 9.32GHz The polar plot at 14.88GHz frequency is shown in Fig.4 below.
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Dual Band Microstrip Antenna for X-Band Applications (IJSRD/Vol. 4/Issue 05/2016/238)
[7] Shung-hyun Lee and Youngje Sung, “Multiband Antenna for Wireless USB Dongle Applications,” IEEE Antenna and Wireless Propagation, Vol.10, 2011.
Fig. 4: Polar plot at 14.88GHz By simple visual inspection, we conclude that polar plot for 14.88GHz is not up to the mark. However, the gain obtained is 7.6dB. The designed antenna is subjected to far-field radiation pattern simulated at the corresponding resonant frequencies. The 3D view of Far field pattern for designed antenna is shown below in Fig. 5.
Fig. 5: Farfield Pattern IV. CONCLUSION We have designed a dual band antenna operating in X-band. The simulated result is carried out to match the antenna result with the measured one and they are in close agreement with each other. The value of VSWR is obtained below 2 for both the operating frequencies which shows stable radiation pattern. REFERENCES [1] Balanis, C. A., Antenna Theory: Analysis and Design, 2nd Edition, John Wiley and Sons Inc, Wiley Reprint, New Delhi, India, 2007. [2] A. Khidre, Kai Fang Lee, Fan Yang, A. Eisherbeni, “wideband circularly polarized E-Shaped Patch Antenna for wireless application(wireless corner)” Antennas and Propagation Magazine, IEEE, Volume: 52 , pp.219 229, 2010. [3] Anguera, J, et al, “Dual Frequency Broadband Microstrip Antenna with A Reactive Loading And Stacked Elements”, Progress In Electromagnetics Research Letters, Vol.10, 1 – 10, 2009. [4] Maci, S and G.B.Gentili, “Dual Frequency Patch Antennas”, IEEE Antennas and Propagation Magazine, Vol.39, No.6, December 1997. [5] D. Bhardwaj, D. Bhatnagar, S. Sancheti, and B. Soni “Design of square patch antenna with a notch on FR4 substrate.” IET Microwaves, Antennas & Propagation, Vol.2, No.8, pp880-885, 2008. [6] Pozar, D.M, “Microstrip Antennas”, Proceeding of the IEEE, Vol.40, No.1, January 1992.
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