Stepped Rectangular Dielectric Resonating ANENNA for 5.0 Ghz Wireless LAN Applications

Stepped Rectangular Dielectric Resonating ANENNA for 5.0 Ghz Wireless LAN Applications

Meghna Kucheria1 , Vijendra Maurya2, Parikshit Vasisht3, Taruna Sharma4 , Dr. Neela Chattoraj5

1M.tech Student

2 Assistant Prof.(E&Tc) Gits Udaipur

3 Assistant Proffesor in Apeejay Stya University, Sohna

4ph.D Student In Y. M. C. A. U. S. T, Faridabad

5 Assosiate Professor – Bit Mesra Ranchi

Abstract This paper presents an approach which combines the two Dielectric Resonating Antennas together as if one resonator is loading the other one. A stepped DRA is presented here which produces enhanced bandwidth in micro and millimeter region of spectrum. A new design of compact and stacked DRA is presented which gives a bandwidth of 34% and a return loss of – 39 db .This design uses two materials one is Rogers RT 5880 as a thin dielectric having a r = 2.2 and the other one is Rogers TMM10 having a r =9.2. The software used for the simulation is the CST Microwave Studio which is an analytical tool that provides an accurate 3D EM simulation results for high frequency design.

Keywords Microstrip Antenna, VSWR, DRA, Stacked, Broadband.

1. INTRODUCTION

   MODERN communication systems require wide bandwidth to support the demand of high data rate transfer for various multimedia applications. To fulfil this requirement, most wireless mobile systems have to be operated at the millimetre wave frequencies [1]-[2]. For ease of space allocation, it is highly desirable to have small size, low profile equipment. Hence, the antennas for modern wireless communication system should be low in profile and efficient in high frequencies. Dielectric resonator antennas (DRAs) have attracted broad attentions in various applications due to their attractive features in terms of high radiation efficiency, light weight, small size and low profile [3]-[6]. Dielectric resonator (DR) antennas are attractive due to their advantages of low loss and high efficiency and research to broaden its bandwidth is being conducted. Over last decades, various bandwidth enhancement techniques have been developed for DRAs. An overview on these techniques has also reported in [6], where these techniques were classified into three broad categories: Lowering the inherent Q -factor of the resonator; using external matching networks; and combine multiple dielectric resonators

   Dielectric resonator antennas (DRA) have been the interest of research and investigation due to its highly desirable characteristics such as small size, light weight, highly efficient in microwave and mm wave spectrum. The most popular shape studied for practical antennas applications have been the cylindrical dielectric resonator antennas, rectangular dielectric

   resonator antennas, spherical dielectric resonator antennas and many more different structure are reported. The stacked DRA has also been tested [7]-[12] with a resulting increase in bandwidth that is much wider than the bandwidth of the micro strip antennas. Two or multi- resonators are defined as those having different sizes with the same or different dielectric materials, they may be loaded or separated from each other. The excited modes in the resonators may be the same or not. For the same modes, the corresponding radiation performances have a good agreement. For the different modes, similar patterns can also be obtained after choosing suitable parameters.With the above approach, an earlier design is a pair of slot coupled-DRAs [13]. The proposed structure consists of two rectangular dielectric resonators that are displaced near the two edges of a single slot on a ground plane. Since the two DRAs have the same shape and material but the different sizes, it may be possible to get the same resonance modes but with the different resonance frequencies. The advantage of this approach is that each resonator can be tuned more or less- independently, allowing for a great deal of design flexibility, this reduces the complexity in a trial design. The disadvantage lies in the added real-state required, which increases the size of antenna and may preclude some of these configurations from being used in an array environment.

   There is also one alternative approach proposed for the combination of two dielectric resonators together as if one resonator is loading the other one. For example, a dielectric resonator is stacked on the top of the other [14]-[18], or a smaller size dielectric resonator is inserted into another lager size dielectric resonator [19], [20] In this approach, the combined two dielectric resonators can usually operate at the same modes or at the different modes.

2. ANTENNA GEOMETRY AND DESIGN

   Fig.1 Geometry of the antenna (W=40mm, L=40mm, h=15.2)

   Geometry of the proposed antenna is illustrated in Fig.1. As shown initially, the dimensions of the slot are 40x40x14.8 mm3. Dielectric resonating antenna is simulated both at CST and HFSS software. DRA which was simulated on CST has the following specifications:-

   1. It is a stacked DRA which is made up of two dielectric materials

      First is Rogers 5880 with dielectric constant of 2.Second is Rogers TMM 10 with dielectric constant of 9.8

   2. Dimensions of Ground are Width = 40mm, length= 40 mm, and height =1.6 m

   1. Dimensions of Ground are Width = 12mm, length= 8 mm, and height =2.4 mm

   2. Dimensions of Ground are Width = 12 mm ,length= 8 mm, and height =12 mm

   Fig. 2 shows the surface current distribution of the proposed antenna for center frequency of 5.818 GHz.

   Fig 2 Surface current distribution of simulated antenna.

   Fig 3 S11 parameters /Return loss of the Dielectric Resonating antenna

   Fig 4. VSWR v/s FREQUENCY curve.

   As shown in Fig. 3 and 4, the antenna shows S11 and VSWR curve

   Fig 5 Smith Chart

   Fig 6 Electric field

   Fig 7 Directivity

   Fig 8 Axial Ratio

   Fig. 5, 6, and 7 shows the electrical characteristics of the antenna .fig. 8 shows the axial ratio which indicates the polarization of the antenna.

3. RESULTS AND DISCUSSION

   Proposed antenna is simulated by taking r=2.2 and 9.2.Antenna is resonating for frequency ranging from 4.2544- 6.1731 GHz. By taking S11- 10 db and VSWR= 2:1 the bandwidth calculated for every resonating frequency comes out to be 34%. Another frequency range obtained from 13.452-13.806 using the same parameters Simulated DRA is showing 34%bandwidth at a range of 4.19 GHz to 6.13 GHz, which is a very useful band in hand phone, and Bluetooth applications.

4. CONCLUSION

DRA is the device which provides high gain, better return losses more bandwidth, polarization agility as compare to the microstrip patch antenna. MSA is regarded as one of the narrow impedance device until and unless some active device is not attached with that, but by using DRA better frequency range can be obtained .In this design the obtained frequency is

5.1 GHz and the bandwidth obtained is 34%which is quite good as compare to MSA.

REFERENCES

1. Petosa, A., A. Ittipiboon, Y. M. M. Antar, D. Roscoe and M. Cuhaci, Recent Advances in Dielectric Resonator Antenna Technology, IEEE Antennas and Prop-agation Magazine, Vol. 40, No. 3, 35-48, 1998.

2. Mongia, R. K. and P. Bhartia, Dielectric Resonator Antennas – A Review and General Design Relations for Resonant Frequency and Bandwidth, Internaional Jour-nal of Microwave and Millimeter-Wave Computer-Aidel Engineering, Vol. 4, No. 3, 230-247, 1994.

3. LuK, K. M. and K. W. Leung, Dielectric Resonator Antennas,

   Research tudies Press LTD., 2002

4. A. G. Walsh, S. D. Young, and S. A. Long, An Investigation of Stacked and Embedded Cylindrical Dielectric Resonator Antennas, IEEE Antennas Wireless Propag. Lett., vol. 5, pp.130-133, 2006.

5. R.K. Mongia and A. Ittipibon, Theoretical and Experimental Investigation on Rectangular Di-electrical Resonator Antenna, IEEE Trans. Antenna Propag., vol. 45, no. 9, pp.1348-1356, sep. 1997.

6. Debatosh Guha, Yahia and M. M. Antar, New Half Hemispherical Dielectric Resonator Antenna for Broadband Monopole Typed Radiation, IEEE Trans. on Antenna and Prop. vol. 54, no. 12 pp. 3621-3627, Dec. 2006.

7. N. Simons, R. Siushansiana, A. Ittipiboon, and M. Cuhaci, Design and Analysis of Multi Segment Dielectric Resonator Antenna, IEEE Trans. Antenna Propag., vol. 48, pp.738-742, May 2000.

8. A. Abumazwed, O. Ahmed and A. R. Sebak: Broadband Half- Cylindrical DRA for FutureWLAN Applications, 3rd European Conference on Antennas and Propagation, EuCAP, pp. 389-392; 2009.

9. Fan, Z. and Y. M. M. Antar, Slot-Coupled DR Antenna for Dual- Frequency Operation, IEEE TransAntennas Propagat., Vol. AP-45, 306-308, 1997.

10. Kishk, A. A., X. Zhang, A.W. Glisson and D. Kajfez, Numerical Analysis of Stacked Dielectric Resonator Antenna Excited by a Coaxial Probe for Wideband Applications, IEEE Trans Antennas Propagat., Vol. AP-51, 1996-2005, 2003.

11. . Pliakostathis, K., D. Mirshekar-Syahkal, Stepped Dielectric Resonator Antenna for Wideband Applications, in Proc. IEEE Antennas and Propagation Society International Symposium Digest, USA, 2004.

12. Al Sharkawy, M. H., A. Z. Elsherbeni, C. E. Smith, Stacked Elliptical Dielectric Resonator Antennas for Wideband, in Proc. IEEE Antennas and Propagation Society International Symposium Digest, USA,2004.

13. Chair, R., A. A. Kishk, K. F. Lee, C. E. Smith, Broadband Aperture Coupled Flipped Staired Pyramid and Conical Dielectric Resonator Antennas, in Proc. IEEE Antennas and Propagation Society International Symposium Digest, USA, 2004.

14. Kishk, A. A., Experimental Study of Broadband Embedded Dielectric Resonator Antennas Excited by a Narrow Slot, IEEE Antennas and Wireless Propagation Letters, Vol. 4, 79-81, 2005.

    [1]	R. Bekkers and J. Smith, Mobile Telecommunication Standards, Regulations and Applications, Artech House Publications, Chapters 2,	[19]	Rao, Q., T. A. Denidni and R. H. Johnston, A Novel Feed for a Multi- Frequency Hybrid Resonator Antenna, IEEE Microwave and Wireless
    	1999.		Components Letters., Vol. 15, No. 4, 238-240, 2005.
    [2]	P. Bedell, Cellular /PCS Management, Mc-Graw Hill, chap. 27, 1999.	[20]	Esselle, K. P. and T. S. Bird, A Hybrid-Resonator Antenna:
    [3]	Long, S. A., M. W. Mcallister and L. C. Shen, The Resonant		Experimental Results, IEEE Trans Antennas Propagat., Vol. 53, No. 2,
    	Cylindricaldielectric Cavity Antenna, IEEE Trans Antennas Propagat.,		870-871, 2005.
    	Vol. AP-31, 406-412, 1983.

15. . Ong, S. H., A. A. Kishk and A. W. Glisson, Wideband Disc-Ring Dielectric Resonator Antenna, Microwave.Opt. Tech. Lett., Vol. 35, No. 6, 425-428, 2002.