'Design of Compact Dual-Band Microstrip Patch Antenna\r'

'Design of hale Dual-Band Microstrip stain Antenna for GPSK-PCS Operation Ho-yong Kim, Yong-nn Lee, Chung-ho Won, Hong-min Lcc Department of Electronics [e-mail protected] Univerrily hi-Dong, Yeongtong-Cu, Suwon-Si, Kyonggi-do, Korea email: [email protected] com lnlraduetion In recent years, with the advance o f technology, the demand for an barbel operating a1 mutibands i s increasing rapidly. Such as GPS and K-PCS, The multi-hand feelers with oneness eating pon use the multiple resonance technolagy[l] such(prenominal) barbell are difficult lo provide a cheeseparing polarization efficiency for GPS signal reception.\r\nSo the unified GPSIK-PCS dual-band overture using two moveing pan has been proposed in this paper. Referenced dual-band antenna using two alimentation pon has matched poiariration of integrated system. [2] but it has queen- surface size. Proposed antenna uses miniafurizalion technique that is to insect ilits. This technique is to add-on elecVlca l surface length by pussys. [3-5] Operating relative frequency o f proposed Bntenna is greatly lower by slit^. drift hunt blot and satisfying aura patch with four diu o f proposed antenna are virtually 70% and 50% ofreferenced antenna size.\r\nThe proposed antenna composed of a low-profile rounded monopole with a surpass-loaded scent line patch for K-PCS Operation, and a comer-truncated unbent-ring microstrip patch antenna with four-slits for GPS ooeration. Pmposed Antenna Design The geometry and purport parameter of the proposed antenna for compact GPSIK-PCS surgical public presentation i s presented in Figure I. The proposed antenna has the communalality ground plane, but i s supply by separate feeding pon. The antenns for GPS-hand i s realized by using a corner-truncated square-ring microstrip patch with four slits.\r\nThe outer side length and interior ride length are40mm(L,)and IZmm(&) ~ ~ p % t i d printed on a rubrtrale o f thickness 1. 6mm(h) and y, r elative peminiviry (e, :4. 4). The middle ofthe substrate is upstage for inner rectangular d i t area ( b x b ) of patch. pabulum position for right-hand circularly polarized (RHCP) wave deed is placed along x-axis. and the distance of the probe feed away fram the patch center i s denoted as 6 . 6 m m ( / ) . The four-rlitr at the comers are of equal length I3. 5mm(S)and largeness Imm(w). Fig 2(a) shows simulated reNm button of the proposed anlenna for GPS receiving antenna with variant d i t lengths(S).\r\nIt i s noted that the reSonant frequency rapidly lowered with increasingdesign parameter(S). In f h i ~ way, the mad surface current paths are lengthened in the propo~ed designs, and the operating frequency is greatly lowered. 0-7803-8302-8/04/$20. 00 IEEE 3529 02004 Also, the shorted meander line patch antenna with low-profile cylindric monopole top is loaded at the center of square ring patch for K-PCS operation. For brbadband characteristic, cylindrical monopole has a la rge diameter of 6. 2mm(d,) and l e n ~ h 10. 7mm(h2). The eander line patch has a ride lengh Z l m m ( p ) and is connected to the common ground by two same shorting posh, which bring forth a diameter of 2. 2mm(d2). By varying ofthe shorting ports diameter(d2), good impedance matching can easily be obtained. Figure 2(b) shows simulated retum loss for the p r a p ~ ~ e d K-PCS antenna with various slit lengthr(m,) of meander line patch. Meander line patch size can be reduced by increasing inserted slit length. Because of the antenna for K-PCS operation interfere the axile mtio of GPS receiving antenna, the miniatufimion of GPS antenna is limited.\r\n fit in to the experiment, the patch size of GPS antenna for circular polarized operation must he over about twice the size of KPCS antenna with meander line suunurc. In the proposed designs, the bandwidth of3-dB axial mtio is about 13 MHz, which is much large than that required for GPS operation at 1575 MHz. The metrical axial ratio ofthe antenna for GPS operation i s presented in Figure 3. Figure 4 shows careful re” 101 of proposed antenna. The impedance bandwidths (. lOdB retum larr) are about lZOMH~(1744MHr-1864MH~)far K-PCS band and 60MHr (IS46MHr-1606MHz) for GPS-band.\r\nThe isolation between the two feeding pons of the PCS and GPS elemenls is less than -17dB. measured beam panems of the proposed antenna at l8OOMHz and ISROMHz are presented in Figure 5 and 6, respectively. The K-PCS antenna radiation therapy panem at IROOMHz shows a monopole radiation panem, 10 this fype of antenna is adapted for applications on a vehicular communication system. For the GPS anfenna at ISROMHz, good philippic band radiation panem is obtained. Far K-PCS operation the measured pea* antenna stumbles is about 2. 4dBi and t h c gain translations are within O. JdBi, for GPS operation the measured peak antenna gains is about 7. dBi and the vanations of gain does not exist. Conclusion Proposed antenna has a integrate d slmcturc of microitrip patch antenna with two feeds for dual-band oprmtion(GPSiK-PCS). A low-profile cylindrical monopole with a shorted meander line patch i s loaded for K-PCS operation, which rhowr a linearly polarized monopole patkm with broadband characterirlic. The radiating clement for GPS operation is a raw square-ring microstip path with truncated comers with four slits, which provide circularly polarized braadrids radiation panemr. size reduction of proposed antenna is achieved by using slits.\r\nMeander line patch and square ring patch with four . lib of proposed antenna are about 70% and SO% of referenced antenna sire. As the proposed antenna has a compact size for dual band operation, it will be suitable for practical vehicular mobile communication antenna applications. R&E”Ce [I] R. Kronberger, H. Lindenmcier, L. Reiter, J. Hapf, ” Multi hand planar Invencd-F C r a Antenna for mobile Phone andGPS,”2714p-Z717p,AP confer. 1999 3530 [2] I. Y. W u and K. L. Wong, â€Å"Two inlegraled stacked shorted patchantennas for DCSiGPS operations,” Micra wave Opt. Techno1 . Len. , Vol. 30. July, 2001.\r\nI31 S. Reed, L. Desclar, C. Terref, and S. Toutain, â€Å" conciliate Antenna Size Reduction By nitty-gritty Oflnductive Slots,” Micro wave Opt. Teehnol. Len. ,Vol29. Apri, 2001. 1 [41 J. Y. Wu and K. L. Wong, â€Å"Single-feed form-ring Microstip Antenna wilh lruncated comers for Compact ~ircularpolarization Operation,” Electronics lea. , Vol. 34, May,1998. [ 5 ] W. S. Chen, C. K. Wu, and K. L. wong. I Novel Compact Circularly polarized Square Microstrip Antennq” IEEE Trans. ,Antennas Propagat. , Vol. 49, March, 2001, L, = 40mm, L, = 12mm, S = 13. 5mm, t = 5. 74mm. IY = I n ” f = 6. 6″. p = Zlmnr, m, =ZOmm, ml =3. mm, d) = 6. 2mm, d* = 2. 2″. d, =9. 3mm h, = 1. 6mm. h2 =10. 7mm Fib. 1. Geomelly and dimiiiimi ofthe pmpanrd a n t m i l for CPSIK-PCS operation. (a) The variation against par ameter S (b) The variation againsl parmnster m, Fig. 2. Simulated return loss wilh v~riour ImgthsiS) nnd vsriour slit lengthsim,). slit 3531 I E 4 , d B ! -2 1. 560 1. 565 1. 570 1. 575 1. 580 .” -15 FrequanollGHz , I . 1. 5 2. 0 ~r4″enwffi~ 2. 5 Fig. 3. The measured arid ratio. Fig 1 Measured r t b m loss of antenna. . (a) x-2 plane @) x-Y plane Fig 6. Measured radiation panem for GPS operation; f=1580MHz 3532\r\n'