• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.1
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• pp.41-47
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• 2013

This letter describes a dual-band compact monopole antenna with two branches for Wi-Fi applications. The proposed antenna is based on a planar monopole design, and composed of two branches of radiating patches for dual-band operation. The ground size of the antenna matches the ground size of a typical hand-held cellular phone for improved compatibility with mobile phone printed circuit boards. The antenna is designed using a simulator and fabricated with optimized parameters. The fabricated antenna is measured at the lower and higher operating frequencies, and the return loss coefficient, gain, and radiation patterns are determined.

• ETRI Journal
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• v.40 no.2
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• pp.180-187
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• 2018

In this paper, we introduce a ground radiation antenna that uses controlled endless metal rim modes. In the proposed technique, the metal rim mode is tuned and excited as a one-wavelength radiator by a small ground radiation antenna. The proposed antenna occupies a clearance of $1mm{\times}4mm$ in a $30mm{\times}20mm$ ground plane. A metal rim with dimensions of $34mm{\times}24mm$ surrounds the ground plane, and the metal rim is separated from the ground plane by a gap of 2 mm. In addition, a lumped capacitor is inserted between the metal rim and the ground plane to control the characteristic mode of the metal rim such that the resonance of the metal rim is tuned to be equal to the operating frequency. By performing simulations and measurements, we compare the performance of the proposed antenna with that of a reference antenna that does not have an inserted capacitor between the metal rim and the ground plane. The results show that a significant improvement of the radiation performance is obtained by employing the proposed technique.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.6 no.2
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• pp.113-118
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• 2007

KPCS internal antenna in this paper, is designed and fabricated using the theory based on the folded monopole antenna. I propose folded monopole internal antenna which has high gain low profile structure with easy installation into the handset of mobile phone. Design frequency is 1.8 GHz that is a center frequency of Korea PCS frequency band, and the impedance variances due to change of antenna structure as a length and width are simulated. Measurements show that input VSWR range under 2:1 is 1.72 - 1.88 GHz, and radiated H-plane pattern is omnidirectional under passive state. Active sensitivities and output power of phone applied antenna are $-105\;{\sim}\;-108\;dBm$ and $22.5\;{\sim}\;23.6\;dBm$ max., respectively.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.7
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• pp.603-607
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• 2009

In this paper, a GPS antenna is designed by using metal film which can be attached on the case of battery without additional space for antenna in GPS band operation. The proposed metal film has a half-wavelength slot radiator. The slot radiator is fed by th electromagnetic field coupled from the GSM850/PCS band antenna. The proposed GPS antenna obtains about 20 MHz bandwidth(VSWR<3) which can cover entire GPS band. The antenna has an average gain of -3.8 dBi.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.76-78
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• 2011

In this paper, 0.8 GHz and 1.8 GHz dual-band antenna was designed for global system for mobile communications (GSM) and the Long Term Evolution (LTE) The proposed antenna was made using CST Microwave Studio 2009. My script antenna's substrate is Taconic TLY-5 and dielectric constant is 2,2 and has 1.0mm thickness with a compact design of the proposed antenna, Thus it shows that this proposed antenna can be used in Wireless Communication System.

• Journal of Electrical Engineering and Technology
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• v.10 no.1
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• pp.331-337
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• 2015

A novel fully-printed microstrip antenna with negative first resonance and dual polarization is proposed. The radiator is printed on the 1-layer substrate instead of multilayers. The -1st resonance results from a composite right- and left-handed(CRLH) structure that has a circumferentially interlocked gap capacitively coupling a patch with a shorted-ring. This compact antenna is provided with a dual-polarization capability by creating two orthogonal linear polarizations in one body with coaxial feeds. The design is carried out by doing full-wave EM field simulation which is compared with the measurement of the fabricated antenna prototype. The measured results give the gain of 5 dBi and the efficiency of 78% at the -1st resonance mode as the center frequency of a downlink channel of the bandwidth over 20 MHz with 29 dB polarization isolation for mobile communication.

• Journal of Korea Society of Digital Industry and Information Management
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• v.5 no.3
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• pp.99-105
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• 2009

This paper suggests novel signal processing methods for optimal beamforming of smart antenna system in CDMA2000 mobile communication environments. This method utilize characteristics of the reverse pilot channel of CDMA2000 mobile communication systems, and applies them to improve the performance of an adaptive algorithm, which is used to a smart antenna system for beamforming. To perform the best beamforming, it is important to get an exact beamforming algorithm. This paper proposed an algorithm based on Laglange multiplier which has such an adaptive process, and also proposed the method to demodulate the received signal through array antenna using pilot channel in CDMA2000 environment. This paper analysed the enhanced performance of proposed algorithm in various signal environment through signal modeling of physical layer in CDMA2000 reverse link.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.8 no.6
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• pp.551-557
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• 1997

In mobile radio environment, it is well known that the base station antenna height gain factor is 6 dB / octave. But the mobile radio environment is not simple and affected by the terrain contour or the man-made structures, so the antenna height gain factor varies due to the propagation conditions. This paper represents the received signal power gain due to the base station antenna height in the microcell environment on the basis of the flat terrain and sloping terrain model. The gain point which shows the antenna height gain is derived in this paper.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.6
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• pp.706-713
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• 2010

In this paper, the small loop antenna with a parasitic loop structure for penta-band mobile phone application is proposed. This antenna is composed of a feed monopole, a radiating loop antenna with a parasitic loop structure and an additional radiating element. The antenna is printed on the very thin flexible substrate to mount on the dielectric carrier with a volume of 40 mm$\times$11 mm$\times$3 mm. The bandwidth of the proposed antenna is 402 MHz(773~1,175 MHz) for low band and 583 MHz(1,622~2,205 MHz) for high band. As a result, the proposed antenna covers the five bands of GSM850, GSM900, DCS1800, PCS1,900 and WCDMA for a 3:1 VSWR. Moreover, the radiation pattern, gain and efficiency are appropriate for mobile handset. Therefore, this antenna is suitable for small sized multi-band mobile handset applications.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.2 s.105
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• pp.178-183
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• 2006

The proposed triple-band compact chip antenna using coupled meander line and stacked meander structure for mobile RFID/PCS/WiBro. The proposed antenna is designed to operate at 900, 1,800, and 2,350 MHz, and is realized by parasitic coupled and stacked a meander line. Meander lines are using extend length of effective current path more than monopole and contribute miniaturization. The coupled meander line controls the excitations of the mobile RFID and PCS, stacked meander line controls the excitation of the WiBro. The fabricated antenna size is $10.98{\times}22.3{\times}0.98\;mm$. The resonance frequencies are 905 MHz, 1.77 GHz and 2.32 GHz. The impedance bandwidths are 24 MHz, 140 MHz and 92 MHz. The maximum gains of antenna are 0.34 dBi, 2.58 dBi and 0.4 dBi at resonance frequencies.