• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.4
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• pp.772-779
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• 2015

In this paper,a reconfigurable multi-band mobile antenna with switching line for LTE band 13, GSM, K-PCS, WCDMA band. The proposed antenna is planar strip line design and composed of stub shorted to the ground plane and two switching line for proposed band operation. To obtain the optimized parameters, we used the simulator, Using the obtained parameters is fabricated. The numerical and experiment results demonstrated that the proposed antenna satisfied the -6 dB impedance bandwidth requirement while simultaneously covering when the state of sw1 and sw2 on for LTE band 13, the state of sw1 off and sw2 on for GSM, K-PCS, the state of sw1 off and sw2 off for WCDMA. Respectively and characteristics of gain and radiation patterns are determined for a reconfigurable multi-band mobile terminal.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.4
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• pp.441-448
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• 2012

This paper proposes a multiband Multi-Input Multi-output(MIMO) antenna for universal serial bus(USB) dongle application. The proposed MIMO antenna consists of a modified meander strip line and inverted L stub. The two radiating elements of the MIMO antenna are symmetrically placed with respect to the center of the ground plane. The fabricated antenna satisfied a VSWR below 3 and an efficiency over 35 % in the LTE band 13, 17(704 MHz-787 MHz), DCS/PCS/WCDMA band(1.71 GHz-2.17 GHz), and LTE band 7(2.5 GHz-2.7 GHz). The envelope correlation coefficient(ECC) has below 0.45 in the LTE band 13, 17 and 0.1 in the DCS/PCS/WCDMA band and LTE band 7, respectively.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.7 no.3
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• pp.48-55
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• 2008

This paper presents a design of a multi-band infernal antenna for mobile handsets which can cover the major mobile services such as WiBro/WiMAX mobile internet services and Media-FLO/S-DMB services. Using wideband monopole antenna structure, the proposed antenna obtains the wide bandwidth characteristic at high Sequency band to be applicable for new mobile services. Stacking meandered radiator on the wideband monopole radiator and obtaining the different current path and lenga on these stacked radiators, overall antenna volume is effectively reduced. The measured bandwidths (VSWR<3) of the proposed antenna is 270 MHz and 2032 MHz at low and high band, respectively. This antenna can effectively covers major wireless communication bands including Media-FLO, CDMA, GSM, GPS, DCS, PCS, UMTS, WiBro, WiMAX, and S-DMB.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.10
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• pp.1031-1041
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• 2009

A small microstrip monopole antenna for macro-micro frequency tuning over multiple bands is presented. The meander-shape antenna is fabricated on a conventional printed circuit board(FR-4, $\varepsilon_r=4.4$ and tan $\delta=0.02$). The antenna operates over WiBro(2.3~2.4 GHz) and WLAN a/b(2.4~2.5 GHz/5.15~5.35 GHz) service bands with an essentially constant antenna gain within each service band. Two diodes, a PIN diode and a varactor, are embedded into the antenna for frequency reconfiguration. The PIN diode is used for frequency switching(macro-tuning) between 2 GHz and 5 GHz bands while the varactor is used for frequency tuning(micro-tuning) within the service bands, 2.3~2.5 GHz and 5.15~5.35 GHz. Unwanted resonances between the two frequency bands(2 GHz and 5 GHz) are suppressed by filling up the gaps between the meander lines. The antenna gain is essentially constant and higher than 2 dBi within each service band. The measured performance of the proposed antenna system suggests the macro-micro frequency tuning techniques be useful in reconfigurable wireless communication systems.

• 한국정보통신설비학회:학술대회논문집
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• 2002.08a
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• pp.17-20
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• 2002

본 논문에서는 세라믹 칩 안테나를 LTCC로 구현하여 다중 대역 특성을 얻는 방법을 제안하고 있다. 휴대용 단말기에 칩 안테나를 내장함으로 물리적 손상을 피하고 위치추적 시스템(GPS) 대역과 단말기 송수신용 대역, 즉 두 대역 이상 사용 가능하고 ${\varepsilon}_r=7.8$인 세라믹 칩 안테나를 LTCC(Low Temperature Co-fired Ceramic)공정을 이용하여 세라믹 칩 내부에 정합 회로를 구현하여 이중 대역 특성을 갖는 구조에 대해 논의하고 있다. 안테나의 전체 크기는 $16mm{\times}4mm{\times}2mm$ 이며 대역폭은 삽입손실 -10dB 기준 대략 1560MHz에서 2160MHz까지 약 600MHz정도이다. 측정은 접지면의 넓이가50mmx50mm이고 두께=0.7874mm, ${\varepsilon}_r=4.6$인 FR4 기판을 이용하여 측정한다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.5
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• pp.455-462
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• 2015

In this paper, we suggested multiband antenna that can be equipped on a inflatable life-jacket, operating VHF-DSC band(156 MHz), COSPAS-SARSAT band(406 MHz) and GPS band(1,575 MHz) for search and rescue survivors quickly. The GPS band antenna was implemented with a square ring-slot planar antenna, and the COSPAS-SARSAT and VHF-DSC band antenna were implemented meander type dipole antennas. In order to place the antenna on a life-jacket, we installed it on 0.2 mm thickness FR-4 substrate to obtain a flexibility. It appeared that the antenna has -14.6 dB, -30.9 dB, and -18 dB return loss in COSPAS-SARSAT, GPS, and VHF-DSC band, respectively. In addition, its gain has 0.83 dBi, 2.1 dBi in COSPAS-SARSAT and GPS band, respectively.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2014.11a
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• pp.252-253
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• 2014

최근 채널 효율을 향상시키기 위하여 다중안테나(MIMO, multi-input multi-output) 기술이 연구되고 있다. 다중안테나 기술은 송 수신 안테나 개수를 증가시켜 수신 성능을 향상시키고 대역 효율을 향상시키지만 송신 안테나 개수를 늘려야만 대역 효율을 증가시킬 수 있으므로 기존 방송 시스템에 적용하기에는 비용이 많이 드는 단점이 있다. 이에 본 논문은 방송 시스템에 적합한 SIMO(single-input multi-output) 시스템에 FTN(faster than Nyquist)을 적용하여 대역 효율을 증가시키고 수신 성능을 향상시키고자 한다. 또한 MRC(maximum ratio combining) 및 경판정(hard decision)을 적용하여 수신 안테나 개수에 따른 수신 성능을 컴퓨터 실험을 통하여 알아본다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.2
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• pp.195-202
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• 2015

As satellite communications services are showing gradual growth, so are the needs for dual or tri-band antennas greater than performance of conventional single-band antennas. In this paper, a simultaneously operable tri-band antenna for SATCOM(Satellite Communications) is proposed. It is different from conventional methods of implementing tri-band through replaceable horns, while it is designed with a tri-band feed assembly composed of corrugated and dielectric horns and reflectors of gregorian type to transmit and receive tri-band of X, Ku and Ka band simultaneously. And simulated and measured values were compared and analyzed for characteristics of the proposed antenna. In the results, radiation patterns of the proposed tri-band antenna were close to the simulated ones and also met specifications.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.2
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• pp.41-50
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• 2010

In this paper, a multi-band antenna with novel structure for mobile communications is designed and fabricated. The proposed antenna has the Multi-band antenna characteristics by two common-grounded slots with different size and angle. In order to reduce size and to enhance the gain of the antenna, a reflector is consisted of chokes on the three sides. It is optimized by using the CST Microwave Studio commercial software based on the FIA(Finite Integration Algorithm) and PBA(Perfect Boundary Approximation), and then the fabricating and measuring is practiced. As a result of measurement, the reflection coefficient is less than -11 dB(VSWR < 1.8) and the gain of antenna is more than 6dBi at 824~894MHz and 1885-2500MHz.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.10 no.6
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• pp.522-528
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• 2017

In this paper, we propose a multi-band antenna for wearable devices using metal frame coupling. The proposed antenna has a $45mm{\times}35mm$ antenna using metal frame and a ground dual coupling structure. The proposed multi-band antenna in this paper is optimized for small devices such as wearable devices. By using the metal frame as a part of the antenna, the volume of the antenna is reduced and satisfies under VSWR 3:1 impedance bandwidth of 70 MHz (870 ~ 940 MHz) in low frequency band, 280 MHz (1600 ~ 1880 MHz) and 280 MHz (1900 ~ 2170 MHz) in high frequency band. It also verified the applicability of wearable devices by measuring wireless performance indicators such as TRP/TIS.