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THE JOURNAL OF KOREAN INSTITUTE OF ELECTROMAGNETIC ENGINEERING AND SCIENCE. 2015 Apr.; 26(4), 357 364. http://dx.doi.org/10.5515/kjkiees.2015.26.4.357 ISSN 1226-3133 (Print) ISSN 2288-226X (Online) 6 MIMO Hexa-Band Hybrid MIMO Antenna for the Mobile Phone Surrounding Ground 이경호 손태호 Kyeong-Ho Lee Taeho Son 요약 6 PIFA(Planar Inverted F Antenna) + IFA(Inverted F Antenna) MIMO(Multi Input Multi Output),. PIFA IFA. PIFA, IFA. carrier PCB embedded MIMO. CDMA, GSM900, DCS, KPCS, USPCS, WCDMA 6 VSWR 3 : 1. CDMA, GSM900 5.19 3.16 dbi 30.27 48.26 %., DCS, KPCS, USPCS, WCDMA 9.50 5.19 dbi 11.23 30.28 %. Abstract In this paper, we designed and implemented a PIFA(Planar Inverted F Antenna) + IFA(Inverted F Antenna) hybrid MIMO(Multi Input Multi Output) antenna for the hexa mobile communication service band. By the simultaneous operation both PIFA and IFA using the coupled feeding structure, we tried for application to modern mobile phones that have large ground size. A PIFA is applied to the ground area, and an IFA is applied to no ground small space on top of the phone. A diagonal fed MIMO antenna is implemented PCB embedded type without antenna carrier component. Implemented antenna on the bare board measured within 3: 1 for VSWR under hexa mobile communication band as CDMA, GSM900, DCS, KPCS, USPCS, and WCDMA. Measured average gains and efficiencies were 5.19 3.16 dbi and 30.27 48.26 % for the CDMA, GSM900 band, and 9.50 5.19 dbi and 11.23 30.28 % for the DCS, KPCS, USPCS, WCDMA band. It's shown that studied antenna can be applied to the antenna for the modern mobile phone. Key words: Mobile Phone Antenna, Hybrid Antenna, PIFA, IFA, Coupled Feeding. 서론 IT. 2014 ( ) (2014025660). (Department of IT Engineering, Soonchunhyang University) Manuscript received October 22, 2014 ; Revised February 23, 2015 ; Accepted March 3, 2015. (ID No. 20141022-086) Corresponding Author: Taeho Son (e-mail: thson@sch.ac.kr) c Copyright The Korean Institute of Electromagnetic Engineering and Science. All Rights Reserved. 357

THE JOURNAL OF KOREAN INSTITUTE OF ELECTROMAGNETIC ENGINEERING AND SCIENCE. vol. 26, no. 4, Apr. 2015.,.,,,., 2.5G, 3G, 4G. 3G,,.,,.,, IFA.., [1]. (parasitic element) (branch element) [2],[3], [4],[5]., [6],,, [7],[8]. PIFA, IFA [9]. CDMA(824 894 MHz), GSM900(880 960 MHz), DCS(1,710 1,880 MHz), KPCS(1,750 1,870 MHz), USPCS (1,850 1,990 MHz), WCDMA(1,920 2,170 MHz) 6, 2 MIMO,. VSWR. PEA(PCB Embedded Antenna). Agilent network analyzer E5062A, MTG.. 안테나구조및설계 PCB (carrier) PCB embedded. ( ) 4.4, (tan ) 0.019, (t) 0.8 mm FR4 PCB. 64 126 0.8 mm 3, 64 96 mm 2. 1 PIFA+IFA. 1 (a) PIFA, IFA, PIFA IFA. 1 (b). PIFA. PIFA IFA. IFA IFA (short stub). PIFA IFA, [10][11]., MIMO. IFA., PIFA, IFA. 50 CPWG. 0.3 mm, 6.5 mm., 0.3 mm. 358

6 MIMO (a) ( :, : ) (a) Front view(left: front, right: rear) 그림 2. L VSWR Fig. 2. VSWR variation due to L lengths. (b) (b) Detailed view of antenna 그림 1. Fig. 1. Geometry of studied antenna.. 1 PIFA IFA. IFA L, IFA L 1 PIFA L 2 VSWR. (tool) Ansoft HFSS. L, L 1 L 2 1(b). 2 1(b) IFA L VSWR. CDMA GSM900 PIFA IFA L, L 53 mm 47 mm 2 mm. PIFA, IFA., 800 MHz PIFA, 900 MHz IFA. L PIFA IFA 2. L. L 53 mm. 3 1(b) IFA L 1 VSWR. DCS, PCS, WCDMA PIFA IFA L 1. L 1 5.5 mm 11.5 mm 2 mm,. L 1. L 1, DCS. USPCS. 4 PIFA L 2 VSWR. PIFA L 2 359

THE JOURNAL OF KOREAN INSTITUTE OF ELECTROMAGNETIC ENGINEERING AND SCIENCE. vol. 26, no. 4, Apr. 2015. 표 1. Table 1. Optimized values for the geometric parameters of antenna. 그림 3. L 1 VSWR Fig. 3. VSWR variation due to L 1 lengths. PIFA IFA Parameter Dimension (mm) Antenna total W L 64 15 W d 44.5 6.0 L 2 22.5 L 3 14.5 L 4 28.5 L 53.0 L 1 5.5 W 1.0 그림 4. L 2 VSWR Fig. 4. VSWR variation due to L 2 lengths. VSWR. L 2 22.5 mm 16.5 mm 2 mm,. L 2,. L 2, WCDMA. 3 VSWR 1.. 제작및측정결과 5 1. FR4, CPWG. PCB PEA(PCB Embedded Antenna). PCB, MIMO. IFA. PIFA. IFA 5(b),. (1) 6 MIMO S 21 ECC(Envelope Correlation Coefficient). S 21 19 db. (1) S ECC 6 0.04 [12]. MIMO (diversity). 360

6 MIMO (a) S 21 (a) (a) Front (b) (b) Rear 그림 5. Fig. 5. Implemented antenna. ECC MIMO, ECC. ECC 0.2, ECC [12]. 7, VSWR. Agilent E5062A. VSWR 3:1. VSWR 2:1 CDMA GSM900, (b) ECC 그림 6. S 21 ECC Fig. 6. S 21 and ECC of implemented antenna. VSWR 3:1 DCS KPCS, USPCS WCDMA. 7. MTG (chamber). 2D H 8, 2. 8 CDMA, GSM900, DCS, KPCS, USPCS, WCDMA H., 361

THE JOURNAL OF KOREAN INSTITUTE OF ELECTROMAGNETIC ENGINEERING AND SCIENCE. vol. 26, no. 4, Apr. 2015. 그림 7., VSWR Fig. 7. Measured return loss, VSWR and Smith chart. (a) CDMA/ GSM900 표 2. Table 2. Efficiencies and gains of antenna. Freq.[GHz] Eff.[%] Avg.[dBi] Peak [dbi] 0.824 36.11 4.42 0.60 0.846 36.91 4.33 0.17 0.869 33.12 4.80 0.19 0.880 35.34 4.52 0.12 0.894 34.95 4.57 0.02 0.910 33.04 4.81 0.06 0.930 30.27 5.19 0.33 0.960 48.26 3.16 1.68 1.710 19.50 7.10 1.64 1.770 21.41 6.69 0.87 1.820 13.88 8.58 2.93 1.850 13.50 8.70 2.86 1.880 16.21 7.90 1.73 1.910 16.83 7.74 1.33 1.930 16.95 7.71 1.24 1.990 30.28 5.19 1.02 2.110 11.23 9.50 3.44 2.170 22.01 6.57 0.78 (b) DCS/ KPCS/ USPCS/ WCDMA 그림 8. 2D H Fig. 8. Measured 2D H patterns. H.,. 2. CDMA, GSM900 5.19 3.16 dbi 30.27 48.26 %, DCS, KPCS, USPCS, WCDMA 9.5 5.19 dbi 11.23 30.28 %,. 362

6 MIMO. 결론, MIMO. PI- FA IFA,. FR4 PEA., MIMO. 6., CDMA, GSM900, DCS, KPCS, USPCS WCDMA VSWR 3 : 1., CDMA GSM900 5.19 3.16 dbi 30.27 48.26 %, DCS, KPCS, USPCS WCDMA 9.50 5.19 dbi 11.23 30.28 %.. References [1],,, " F ",, 21(7), pp. 726-733, 2010 7. [2] H. Nakano, N. Ikeda, Y. Wu, R. Suzuki, H. Mimaki, and J. Yamauchi, "Realization of dual-frequency and wideband VSWR performances using normal-mode helical and inverted-f antennas", IEEE Transactions on Antenna and Propagation, vol. 46, no. 6, pp. 788-793, Jun. 1998. [3] D. Lin, B. Gaucher, "A branched inverted-f antenna for dual band WLAN application", IEEE Antenna and Propagation Society International Symposium, vol. 1, pp. 2623-2626, Jun. 2004. [4] J. Ollikainen, O. Kivekas, C. Icheln, and P. Vaini-kainen, "Internal multiband handset antenna realized with an integrated matching circuit", in Proc. 12th Int. Conf. Antennas and Propagation, vol. 57, no. 8, Aug. 2009. [5] J. Villanen, C. Icheln, and P. Vainkainen, "A coupling element-based quad-band antenna structure for mobile terminals", Microwave Optical Technology Letter, vol. 49, no. 6, pp. 1277-1282, Jun. 2007. [6] C. Wood, B. Sc, "Improved bandwidth of microstrip antennas using parasitic elements", IEEE Proc, vol. 127, no. 4, Aug. 1980. [7] Kin-Lu Wong, Chin-Hong Huang, "Bandwidth-enhanced internal PIFA with a coupling feed for quad-band operation in the mobile phone", Microwave Optical Technology Letter, vol. 50, no. 3, Mar. 2008. [8] Kin-Lu Wong, Chih-Hong Huang, "Compact multiband PIFA with a coupling feed for internal mobile phone antenna", Microwave and Optical Technology Letters, vol. 50, no. 10, Oct. 2008. [9],, " PIFA IFA ", ITS, 10(4), pp. 65-70, 2011 8. [10],, "LTE ",, 22 (7), pp. 737-743, 2011 7. [11],, "4G MIMO ",, 35(1), p. 47, 2012 5. [12] Constantinos Votis, George Tatsis, and Panos Kostarakis, "Envelope correlation parameter measurements in a MI- MO antenna array configuration", Int. J. Communications, Network and System Sciences, pp. 350-354, 2010 3. 363

THE JOURNAL OF KOREAN INSTITUTE OF ELECTROMAGNETIC ENGINEERING AND SCIENCE. vol. 26, no. 4, Apr. 2015. 이경호 년 2월: 순천향대학교 정보통신공학 과 (공학사) 2015년 2월: 순천향대학교 정보통신공학 과 (공학석사) 2015년 현재: (주)아모텍 주임연구원 [주 관심분야] 휴대폰 안테나설계, 소형 안테나 및 전파전파 2010 364 손태호 년 2월: 한양대학교 전자통신공학과 공학사) 년 2월: 한양대학교 전자통신공학과 공학석사) 년 2월: 한양대학교 전자통신공학과 공학박사) 년 1987년: 금성정밀(주) 중앙연구소 선임연구원 1980년 1981년: 영국 Ferranti사 연구원 1992년 1994년: 천문우주연구원 객원연구원 1999년 2000년: 한국 ITS학회 회장 2002년 현재: (주)에스비텔콤, (주)하이트랙스, (주)스카이크로 스 기술고문 1990년 현재: 순천향대학교 정보통신공학과 교수 [주 관심분야] 위성통신, 휴대폰 안테나설계, 자동차용 전장품 개발 1979 ( 1986 ( 1990 ( 1978