Study and Design of Dual Frequency High Gain and Conformal Microstrip Patch Antenna

Transcription

1 , pp Study and Design of Dual Fequency High Gain and Confomal Micostip Patch Antenna S. Auna 1, K. Sinivasa Naik 2, J. Ramesh 2 and D. Madhu 2 1 Andha Univesity College of Engineeing (A), Visakhapatnam , A.P auna @gmail.com 2 Vignan's Institute of Infomation Technology, Duvvada, Visakhapatnam, Andha Padesh. nivas @gmail.com Abstact. Patch antennas ae cuently unde contemplation fo use in multi band communication systems and high gain applications due to thei captivating chaacteistic, such as low pofile, unidiectional adiation pattens, confomal natue and ease of fabication. In ode to incease the bandwidth, dual band opeation the patches can be designed in a vaiety of shapes. The main goal of this wok is the design of Dual fequency high gain confomal antenna aay mounted on a suface of the cylinde at 2.45GHz and 2.05GHz. The designed antenna aay is acquied by poviding equal squae slots at the opposite cones of the ectangula patch antenna in Dual-band opeation with good impedance matching and high gain is acquied by antenna aay stuctue. Confomal antenna is designed to confom o follow some ecommended shape which is mounted on a cuved suface stuctue. The designed antenna is simulated and optimized by Using High Fequency Stuctue Simulato (HFSS) which can be used in aicafts, missiles etc. Keywods: Confomal; Dual fequency; slots; multi band; high gain; antenna aay; high fequency stuctue simulato(hfss). 1 Intoduction Mico-stip patch antenna plays vey impotant ole in the vaious communication systems [1] because of numeous benefits, such as the small size, light weight, thin pofile, low cost. Howeve, it also has the impefection of the naow fequency bandwidth and lage dielectic loss, so a lot of eseach has been made to enlage mico-stip antenna bandwidth and bette the antenna gain. Theefoe this method is mainly conceted in the following cases: (1) Consideing the dielectic substate thickness. (2) Consideing the substate which having low dielectic constant. (3) Consideing the layout of patch [2]. (4) Consideing non-plana patch Antenna layout ISSN: ASTL Copyight 2017 SERSC

2 In geneal the gain of the single mico-stip patch antenna having gain 6~8dB. A Micostip adiating elements ae used often used to consist of mico-stip aay elements in ode to attain a lage gain o specific diectivity. Confomal antennas obtained geat inteest, as cafting of antenna on stuctues tagets the poblem of the adiation fom smooth convex objects, by using confomal antenna aay the field view can be extended up to The concept of confomal antenna most impotantly found in the smat skin appoach method, which demands the inclusion of non-plana active antennas in cuved sufaces adapted to the skin of the platfoms like aeospace applications missiles, vehicles etc.[8] Confomal antennas on some cuved suface, have thei shapes esolved by some specific EM popeties[10] such as antenna beam shape, beam width, bandwidth o angula coveage. The mico-stip antennas ae confomal in natue and hence they can be used simply on any cuved suface by just changing the shape of the antenna gound plane. If the gound plate and substate is made confomal then the patch can also be wapped on it as MSA and it can be ealized with the same tansmission model equations used fo plana antenna [6], without getting any unacceptable changes in its adiation chaacteistics. Thee ae vaious feeding methods that can be used fo feed Mico-stip patch antenna design. The most commonly used feeding methods ae [3]: 1.Mico-stip feed line; 2.Coaxial pobe feed; 3.Apetue coupling; 4. Poximity coupling. Mico-stip feed line feeding is used in this designing. 2 Realization of Antenna Paametes A single MSA is designed on HFSS 3D simulation tool, which configue the base fo designing of confomal antenna. Fo establishing patch dimensions fist a theoetical design has to be done by [7] specifying dielectic constant, Fequency of opeation and thickness of substate to be taken: Fo Effective adiation, patch width is calculated as : w 2 f 0 c 1 2 Whee c is the velocity of light in fee space. 2. Fomula fo effective dielectic constant of MSA, (1) eff 1 1 h w whee W/h >1 1 2 (2) 3. Fo calculation of length extension, Copyight 2017 SERSC 237

3 L0.412h h w h w (3) 4. Fo dominant mode, the esonant fequency is given as: L eff c 2 f 0 eff (4) F v 0 2 L L Leff 2 L (5) (6) 3 Dual Fequency Patch Antenna Fo Dual band pefomance two squae slots at equal cones of MSA ae intoduced. Squae slot width and length ae attained by tial and eo method fo a specified new band of fequency. w 1 = 9mm, L 1 = 10mm Substate is Roges RT/duoid 5880, Resonant fequencies ae 2.45GHz & 2.05GHz, Radiation box at λ/4 distance fom antenna should be taken. Fig. 1. Antenna unit stuctue 238 Copyight 2017 SERSC

4 Fig. 2. Designed model of MSA 4 Dual Fequency Linea Aay Patch Antenna A 4-element linea aay with equal spacing is designed by using HFSS. The linea aay antenna [9] is fomed as shown in below. Unifom spacing of 0.5λ, is taken whee λ is the esonating fequency coesponding wavelength, the esonating fequency is 2.45 GHz. Aay patten gain eached is 13.95dB. Patch antenna expeiences many losses i.e. loss due to the feedes and adapte and cable loss. That leads to 1 to 2 db loss in the gain. VSWR of 1.68 & 1.7 was obseved. In most of the application a VSWR of 1.5 to 2 is equied [5]. The second impotant paamete of aay is the beam width, which was equied to be in the ange 20 0 to30 0, wheeas the expeimental esults show a beam width of about Dual Band Patch Antenna Confomed On Cylinde The dual band cone cut Mico-stip Patch Antenna is mounted on the suface of the cylinde of adius and height h, as shown in Fig.1. Fig. 3. Dual fequency antenna on suface of a cylinde (Confomal antenna) Copyight 2017 SERSC 239

5 6 Simulated Results 240 Copyight 2017 SERSC

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7 Table 1. Optimized antenna paametes Mico-stip patch antenna Dimension afte paametic analysis(in mm) Patch antenna Width 45 Length 48 Quate wave tansfome Width Length Tansmission Feed line Width Length Conclusion The ectangula naow band patch antenna is tansmitted into the Dual band patch antenna by ceating cut-down squaes at symmetical cones theefoe the band of opeation is inceased and also by optimizing antenna paametes the unit gain value 242 Copyight 2017 SERSC

8 obtained is 7.57dB, the maximum gain of 13.95dB is obtained by 4- element aay, theefoe the antenna and aay have the vey good adiation pefomance and inceased band of opeation Also plana Mico-stip antenna is confomed on cylindical suface by ANSOFT HFSS wapping method, which is one of the advanced antenna design technique nowadays. Thus Mico-stip patch antennas ae low pofile and yet the most utilizable fom of antennas. Refeences 1. Zhong Shishun. The theoy of mico-stip antenna and application Xian_The Publishing House of XIDIAN Univesity_1991_ Y X Guo_K M Luk_K F Lee. A dual-band patch antenna with two U-shaped slots [J]. Micowave and Optical Technology Lettes2000_26(2). 3. Keith R. Cave, James W. Mink, Micostip Antenna Technology, IEEE Tansactions on Antennas & Popagation, Vol-29, No. 1, Januay Las Josefsson and Patik Pesson, Confomal Aay Antenna Theoy And Design, The IEEE Pess seies on electomagnetic wave theoy, R. J. Mailloux, J. Mcllvenna and N. Kenweis "Micostip aay technology", IEEE Tans. Antennas Popagat., vol. AP-29, no. 1, pp Constantine A. Balanis, Antenna Theoy Analysis and Design, Wiley Publications, Moden Antenna Design, Thomas A. Milligan, IEEE Pess, John Wiley & sons Publications K. Sinivasa naik and S. Auna, Investigation On the geneation of patten fo Maine Rada Applications, in Indian Jounal of Science and Technology(INDJST), vol 9(7), 84169, pp, 1-7, Febuvay P. V. Hema Latha, S. Auna and K. Sinivasa Naik, Analytical analysis of 8-element ing Width ectangula micostip patch antenna Aay, Intenational Oganisation of Scientific Reseach [IOSR], volume 11, Issue 5, ve, III (sep.-oct, 2016, pp Geneation of Radiation pattens fo tiangula on pedestal of distibutions Asian Academic eseach Jounal of Multidisplinay (AARJMD)ISSN: , volume 3, Issue4, (Apil 2016), page:43-55, (Authos: S. Auna, D. G. S. N Raju and D. P. Si Devi. Copyight 2017 SERSC 243