DESIGN OF DUAL BAND 1X2 MICROSTRIP PATCH ANTENNA ARRAY FOR GPS RECEIVERS

Transcription

1 DESIGN OF DUAL BAND 1X2 MICROSTRIP PATCH ANTENNA ARRAY FOR GPS RECEIVERS S. Subhashini and S. Sadhish Pabhu B. S. Abdu Rahman Univesity, Chennai, India ABSTRACT An H shaped dual band mico-stip patch antenna aay is designed, simulated and fabicated fo Global Positioning system (GPS) eceives coveing L1 and L5 fequencies of GHz and GHz espectively. Antenna paametes like etun loss,, impedance matching, adiation patten and diectivity ae analyzed. The designed antenna has a bandwidth of 1.3% and 2.2% fo GPS L1 and L5 eceives espectively. In addition to it, the mico-stip patch antenna aay is fabicated using co-axial feed mechanism and tested. The antenna had a etun loss of -27 db and - 18 db fo GPS L1 and L5 band espectively. Keywods: aay antenna, mico-stip patch antenna, GPS eceives. 1. INTRODUCTION In the last decades, thee has been a apid gowth in the antenna design of integating GPS into teestial wieless communication system. Global Navigation Satellite System (GNSS) is the standad univesal tem fo adio navigation satellite systems that povide autonomous geo-spatial positioning with global coveage. The GNSS pemits eceives to detemine thei location using signals tansmitted fom satellites. Aviation eceives utilizes GPS L1 and L5 adio navigation [1]. Mico-stip patch antenna has been wide employed in seveal applications due to low cost, low pofile and easy fabication [2]. The antenna is designed fo a GPS satellite system navigating eceive, opeating at GHz and GHz fequency bands. In the liteatue, a numbe of studies on a dual band opeation coveing GPS L1 and L2 fequencies [3]-[4] have been epoted along with mobile applications [5]-[7]. This pape poposes a co-axial feed aay antenna fo GPS opeation in L1 and L5 band. This pape is oganized as follows: Section II descibes the stuctue and design of the single patch and aay antenna, Section III shows the esults and discussion, while the pape is concluded in Section IV. 2. ANTENNA DESIGN The geomety of the designed aay antenna is shown in the Figue-1. It is composed of two identical patches, two co-axial feed and a gound plane. The patch antenna is employed with two vetical slots that ae esponsible fo GPS L1 band fequency esonance and one hoizontal slot that is esponsible fo GPS L5 band fequency esonance. The electical length is alteed by cutting slot such that the cuent doesn t flow in the opposite diection [8]-[9]. Figue-1. Geomety of the aay antenna. The dimension of the single patch antenna is shown in the Figue-2 and can be calculated with the following equations [10]-[13]. Figue-2. Patch antenna dimension. Width The width (W) of the patch antenna contols the input impedance and adiation patten and is given as W 2 f c ( 1) 2 (1) c = Velocity of light = 3x10 8 m/s f = Resonance fequency = 1.37x10 9 Hz = Dielectic constant = 4.4 (FR4 substate) Effective dielectic constant 4133

2 Most of the electic field lines eside within the substate and a few in the ai as shown in Figue-2. Hence effective dielectic constant, must be detemined in ode to take in account of the finging field and wave popagation in the line. The effective dielectic constant ( ) can be given as h w (2) The position of the feeding pobe is optimized by heuistic appoach so as to achieve a bette impedance matching. The detail dimension of a single adiating patch is given in the Figue-3. The patch suface is x mm 2, while the hoizontal and the vetical slot dimension is 2 x 22 mm 2 and 35 x 5 mm 2, espectively. (9) h = height of the substate = 1.6 mm Length The finging fields along the width of the stuctue as shown in the Figue-2 ae taken as adiating slots. Due to this, the dimension of the patch antenna will be seen electically bit lage than the initial dimension. This vaiation in dimension is named as extended length (ΔL) that is given by L h w h (3) w 0.8 h The actual length of the patch antenna will be calculated fom the subsequent equation L Leff 2 L (4) L eff = Effective length of the patch L eff c (5) 2 f Feed position The feed coodinates ae calculated using the following equations (6) (7) Figue-3. Geomety of single patch antenna. Summay of the design Table-1. Dimension of the designed antenna. Paamete Cente fequency Length of the patch (L) Width of the patch (W) Height of the substate (h) Dimension 1.37 GHz mm mm 1.6 mm Dielectic constant (ɛ ) RESULTS ANS DISCUSSIONS The simulation is caied out using the commecially available electomagnetic simulation softwae HFSS (High Fequency Stuctual Simulato). The top and back view of the pototype is shown in Figues 4 and 5. The measued and simulated eflection coefficients of the poposed 2 x 1 aay ae illustated in Figue-6. The simulated etun loss of the aay antenna fo GPS L1 and L5 fequency band is -35 db and -27 db espectively having -10 db as efeence. The measued etun loss appeas to be -27 db and -18 db at L1 and L5 band espectively was obtained by using Netwok analyze which can futhe be impoved by good testing envionment. Thee is a little vaiation between the simulated and measued esults due to SMA connecto, cable effects and fabication impefection. (8) 4134

3 fequency band is 0.30 and 0.73, wheeas measued esult is of 1.09 and The impedance matching chat given in the Figue-8 shows that L1 and L5 band has 51.79Ω and 45.92Ω impedance matching, espectively. 5 4 Name X Y Cuve Info db((1)) Setup1 : Sw eep m3 db((1))_ Impoted m Simulated Results - Red Colou Measued Results - Blue Colou Figue-4. Top view of the pototype. d B ( V S W R ( 1 ) ) m3 m4 Feq [GHz] Figue-7. Simulated and measued of the poposed antenna. 6 Impedance Figue-5. Back view of the pototype. Retun Loss 5 4 Name Cuve XInfo Y e(z(1,1)) Setup : Sw eep Name X Y Cuve Info db(s(1,1)) Setup : Sw eep m3 db(s(1,1))_ Impoted m e (Z (1,1 )) 3 d B (S (1,1 )) m3 Simulated Results - Red Colou Measued Results - Blue Colou m4 1 Feq [GHz] Feq [GHz] Figue-6. Simulated and measued eflection coefficients of the poposed antenna. Figue-7 shows simulated and measued of the aay antenna at GPS L1 and L5 fequency band. The simulated esults of the fo GPS L1 and L5 Figue-8. Simulated impedance value of the poposed antenna. The amount of enegy adiated fom the antenna is gaphically shown in the adiation patten of the poposed antenna is given in the following Figue-9. Fo GPS L1 and L5, the amount of enegy adiated is given as 2.95 db and db, espectively. 4135

4 Name Theta Ang Mag Radiation Patten Cuve Inf o db(etotal) Feq='1.17GHz' Phi='0deg' db(etotal) Feq='1.575GHz' Phi='0deg' GPS band Retun loss (db) Table-1. Compaative analyses. Simulated esults Impedance matching (Ω) Retun loss (db) Measued esults Impedance matching (Ω) L L Figue-9. Radiation patten of the poposed antenna. The diectivity of the poposed aay antenna is depicted in the Figue-10. The diectivity fo GPS L1 and L5 is given as 2.63 db and 4.55 db, espectively. Name Theta Ang Mag Diectivity Cuve Inf o db(ditotal) Feq='1.17GHz' Phi='0deg' db(ditotal) Feq='1.575GHz' Phi='0deg' 4. CONCLUSIONS An H shaped dual band mico-stip patch antenna aay fo GPS eceives has been poposed. The antenna suppots a dual band opeation with good pefomance in GPS L1 and L5 fequency bands. The dual band opeation has been obtained by cutting vetical and hoizontal slots in the patch antenna. The simulated and measued esults yield bette eflection coefficients, and impedance matching at both GPS L1 and L5 fequency bands. Futhe, the efficiency of the poposed antenna in all aspects can be enhanced with single feed powe divide mechanism. REFERENCES [1] Juan Blanch, Todd Walte, and Pe Enge, Satellite Navigation fo Aviation in 2025, Poceedings of the IEEE, Volume 100, May 13 th, [2] Constantine A Balanis, Antenna Theoy, Analysis and Design, John Wiley and Sons Inc, 2 nd Edition, Figue-10. Diectivity of the poposed antenna. Compaative analysis of simulated and measued esults [3] Umniyyah Ulfa Hussine, Mohammad Taiqul Islam, Nobahiah Misan, A New I Slotted Compact Micostip Antenna fo L1 and L2 Bands, Poceeding of the 2011 IEEE Intenational Confeence on Space Science and Communication, July 2011, Penang, Malaysia. [4] A.J. Abdul-Qade, Y. E. Mohammed Ali, A High Gain Double laye Dual Band Micostip Antenna fo GPS Applications, Intenational Confeence on Micoelectonics, Communication and Renewable Enegy (ICMiCR-2013). [5] Oluyemi P. Falade, Yue Gao, Xiaodong Chen and Clive Paini, Stacked-Patch Dual-Polaized Antenna fo Tiple-Band Handheld Teminals, IEEE 4136

5 Antennas and Wieless Popagation Lettes, Volume 12, [6] Shun-Yun Lin and Kuang-Chih Huang, A Compact Micostip Antenna fo GPS and DCS Application, IEEE Tansactions on Antennas and Popagation, Volume 53, Numbe 3, Mach [7] Haide A.Sabti and Jabi S.Aziz, Dual Band MSA Designs fo GPS and GSM Applications, ARPN Jounal of Engineeing and Applied Sciences, Volume 5, Numbe 5, May [8] S. Bhunia, Effects of Slot Loading on Mico-stip Patch Antennas, Intenational Jounal of Wied and Wieless Communications, Volume 1, Issue 1, Octobe, [9] Sakshi Aoa, Gauav Gupta, Vikas Gupta, Reduction in the Resonant Fequency of a Simple Squae Patch Antenna by Loading an Asymmetical E-Shaped Slot in Patch, Intenational Jounal of Advanced Reseach in Compute Science and Softwae Engineeing, Volume 3, Issue 7, ISSN: X, July [10] T. Duga Pasad, K.V.Satya Kuma, MD Khwaja Muinuddin, Chisti, B.Kanthamma, V. Santosh Kuma, Compaisons of Cicula and Rectangula Micostip Patch Antennas, Intenational Jounal of Communication Engineeing Applications-IJCEA, Volume 02, Issue 04, ISSN: , July [11] Pof. Jaikaan Singh, Pof. Mukesh Tiwai, Ms.Neha Patel, Design and Simulation of Mico-stip E- shaped Patch Antenna fo Impoved Bandwidth and Diective Gain, Intenational Jounal of Engineeing Tends and Technology (IJETT), Volume 9, Numbe 9, Ma [12] Sukhjitkau, Paminde Singh, Avta Singh Butte, Design and Analysis of Poximity Mico-stip Patch Antenna with Paasitic Lines, Intenational Jounal of Applied Sciences and Engineeing Reseach, Volume 3, No. 2, [13] B. Sai Sandeep, S. Seenath Kashyap, Design and Simulation of Mico-stip Patch Aay Antenna fo Wieless Communications at 2.4 GHz, Intenational Jounal of Scientific and Engineeing Reseach, Vol. 3, Issue 11, ISSN , Novembe