Modification of Planar Inverted-F Antenna for Wireless Applications

Transcription

1 Modification of Planar Inverted-F Antenna for Wireless Applications Amandeep Singh 1, Hardeep Singh 2, Navdeep Kaur 3 1,2,3 Dept. Of ECE, Baba Farid College Of Engineering and Technology, Bathinda, Punjab, India Abstract: This Paper is focused on the design and development of a multi-band planar inverted F- antenna for various wireless applications. Thus, a brief discussion of various antenna structures and designs that supports multiband operation is out lined. In this paper, a compact ultra-thin multiband planar inverted-f antenna is designed and optimized having independent controls of the resonant frequency bands for GSM, UMTS, WiMAX, WLAN and C-Band. The objective of research is as follow. Planar Inverted-F Antenna (PIFA) is chosen to form the basis in this paper due to its low profile, ability to support multiple bands. PIFA has proved to be most widely used internal antenna in cellular communication. Keywords: Planar Inverted-F Antenna (PIFA), Return Loss, Gain, Bandwidth, Effect of Shorting strip width. I. INTRODUCTION In the past few years the need and popularity of antennas which supports multiple bands has been rising. As we know that demand is due to advancements in wireless communication technologies and rapid increase of cellular service users. As a result, there is surge for research and development of multi-band and wideband antennas operating on several standards [2]. For handheld devices several antenna structures have been developed and implemented. Many of them are external antenna structures and many are internal structures. Most of these antennas were developed to meet the demand of the increasing cellular phone market. The operation of these antennas is mainly focused on supporting some major communication standards worldwide such as GSM, DCS, PCS, UMTS (3G), WiMAX, UWB and 4G LTE etc. [13,8].In this work compact PIFA is proposed and presented for various wireless applications. The effects of different feed positions and shorting wall width are studied. The proposed antenna satisfies the return loss, VSWR and bandwidth for applications within frequency range from GHz. The measured reflection coefficient, radiation pattern, VSWR and gain are characterized. II. EFFECT OF PIFA ON PERFORMANCE PARAMETERS This techniques increase the Bandwidth for PIFA.The dimensions of the ground plane affect the bandwidth coverage. By varying the size of the ground plane, the bandwidth of a PIFA can be adjusted and optimized. Thick air substrate can be used to lower the Q factor and increase the bandwidth. The location and spacing between two shorting posts can be adjusted accordingly. Use of stacked elements may also increase the bandwidth. Reduction in PIFA dimensions can be achieved by following approaches:one method of reducing PIFA size is by shorting the antenna. However, this approach affects the impedance at the terminals. This can be compensated with capacitive top loading. Although use of capacitive loading reduces the resonance length from λ/4 to less than λ/8 but at the expense of bandwidth and good matching. The capacitive load can be produced by adding a plate (parallel to the ground) to produce a parallel plate All Rights Reserved 85

2 III. DESIGN AND PROCEDURE The optimization and simulations of the antenna is carried out using High Frequency Structure Simulator (HFSS). HFSS is a high performance full wave electromagnetic (EM) field simulator for arbitrary 3D volumetric passive device modeling that takes advantage of the familiar Microsoft Windows graphical user interface. It integrates simulation, visualization, solid modeling, and automation in an easy to learn environment where solutions to your 3D EM problems are quickly and accurate obtained. Ansoft HFSS employs the Finite Element Method (FEM), adaptive meshing, and brilliant graphics to give you unparalleled performance and insight to all of your 3D EM problems. Ansoft HFSS can be used to calculate parameters such as S-Parameters, Resonant Frequency and Fields. IV. MULTIBAND PIFA WITH TWO SLOTS ON THE RADIATING ELEMENT TABLE 1: DETAILED DIMENSIONS OF PROPOSED MULTIBAND ANTENNA Sr. No. Parameter Dimension (mm) 1 Length of Ground, Lg 40 2 Width of Ground, Wg 40 3 Length of Patch, Lp 26 4 Width of Patch, Wp Length of Slot, Ls Width of Slot, Ws 4 7 Height of Substrate, h Distance b/w Ground Plane and Radiating Element, H Width of Shorting Strip, Wss 3 10 Width of First Supporting Wall, S Width of Second Supporting Wall, S Width of large slot,w 12 Figure 1: 3-D view of proposed Multiband PIFA in HFSS with two slots V. RETURN All Rights Reserved 86

3 The return loss plot for proposed multiband PIFA design shown in Figure 3. Figure 3: Simulated Return Loss of Multiband PIFA It can be seen that the proposed antenna resonate at three different frequencies 2.02GHz, 3.5GHz and 5.9GHz. The return loss db, db and db obtained at resonant frequencies with the operating bandwidth 14.35%, 11.73% and 19.32% respectively. VI. VOLTAGE STANDING WAVE RATIO (VSWR) The simulation results for VSWR for the frequency range from 1 to 7 GHz is shown in the Figure 4. The value of VSWR can be seen in the plot and has to be less than 2 db at three resonant frequencies which is desirable for most of the wireless applications. Figure 4: Simulated VSWR of Multiband PIFA VII. RADIATION PATTERN The simulated 3D radiation pattern obtained from the simulation of multiband PIFA is shown in Figure 5. It can be observed from the plot the proposed antenna is a good radiator with almost omni directional radiation pattern which supports various cellular and non-cellular frequency All Rights Reserved 87

4 Figure 5: Simulated 3-D radiation pattern of multiband PIFA Gain The overall gain of the antenna obtained after simulation is shown in Figure 6. A peak gain of 2.97 db is observed at resonance. Figure 6: Simulated 3-D Gain Plot of Multiband PIFA VIII. EFFECT OF SHORTING STRIP WIDTH ON THE MULTIBAND PIFA PERFORMANCE We will vary the width shorting strip from 0.5 to 5 mm. We will obtain the diffeent results. We can consider the width 2 mm for proposed antenna and the most convenient for the bandwidth and the resonant frequency. The effects of shorting strip width on different parameters of antenna are shown below: Table 2 : Effects of Shorting Strip Width on different Parameters of multiband PIFA Width of Shoting Strip (mm) Resonating Frequency (GHz) Return Loss (db) VSWR (db) Bandwidth (%) Gain (db) All Rights Reserved 88

5 IX. CONCLUSION The main objective of this work is to design a multiband planar inverted-f antenna for wireless applications and study the effect of slot width and shorting strip width. Here coaxial feed method is used to excite the planar inverted-f antenna. It has two slots on radiating part which improves operating bandwidth and resonance of the antenna. Using High Frequency Structure Simulator, simulation has been carried out to analyze and optimize the antenna s characteristics and performance. From the simulation results, it has been observed that the antenna is able to operate at desired resonant frequencies and have good operating bandwidth supporting multiple bands. The design proposed in this work can be extended for supporting MIMO applications for the devices which supports LTE and WLAN technologies. REFERENCES 1. A.Khare and P.Bhulania, Study of Planar Inverted-F antenna in WiMAX Band International Journal of Enginering & Technical Resarch, Vol.-2, Issue-5, A.P Dabhi and S.K Patel, Response of Planar Inverted-F antenna over different dielectric substrates International Journal of Scientific & Technology Resarch, Vol.- 3, Issue-5, B.Sujatha, K.Saranya, N.Y.Naseera and B.Bhuvaneswari, Realization of various Planar Inverted-F Antenna International Journal of Electrical, Electronics and Data Communication, Vol.-2, Issue- 4, I.Elfergani, A.S.Hussaini and J.Rodriguez, Wideband Tunable PIFA antenna with loaded slot structure for mobile handset and LTE applications Radio engineering, Vol.- 23, No.-1, N.Ojaroudi, H.Ojaroud and N.Ghadimi. Quad-Band Planar Inverted-F Antenna (PIFA) for Wireless Communication Systems Progress In Electromagnetic Research Letters, Vol.-45, pp.51-56, N.Khan. Design of Planer Inverted-F Antenna International Journal of Advanced Technology in Engineering and Science, Vol.-02, Issue No. 05, S.Luthra and K. Kaur. Small Size Planar Inverted-F Antenna For WiMAX applications International Journal of Electrical & Electronics Engineering, Vol. -1, Issue-2, A. Sharma, R.P.S. Gangwar and S.S Chauhan, Design and simulation of multiband Planar inverted-f antenna for mobile phone applications International Journal on Computer Science and Engineering, Vol.-5, No.- 05, A. Elouadih, A.O. Said and M.M Hassani, Design and Parametric simulation of a miniaturized PIFA antenna for the PCS band, pp , G.M.Khanal. Design of a Compact PIFA for WLAN Wi-Fi wireless Applications International Journal of Engineering Research and Development, Vol.- 8, Issue-7, pp.13-18, M. Abri, N. Belgacem and W. Belgacem. New GSM, DCS and GSM/DCS PIFA Antennas Designs for Wireless Networks Applications International Journal of Information & Network Security, Vol.-2, No.4, pp , N.Kumar and G.Saini, A Multiband PIFA with Slotted Ground Plane for Personal Communication Handheld Devices International Journal of Scientific and Research Publications, ISSN , N.Kumar, A Multiband PIFA antenna for handheld devices ME Thesis, Panjab University, Chandigarh, Pengcheng Li, J.Pan, D.Yang and Z.Nie, A novel quad band PIFA for mobile phone handset Progress In Electromagnetics Research, Vol.-137, pp , R.G.Villanueva, R.L Miranda and J.A.T Mendz. Ultra Wideband PIFA for Mobile Phone Frequencies and UWB applications Progress In Electromagnetics Research, Vol.- 43, pp , All Rights Reserved 89