• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.10 no.3
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• pp.199-205
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• 2017

In a small cell base station used in densely populated areas, a dual polarized multiple antenna(MIMO) is mainly used to increase the cell capacity. This paper demonstrates a dual-polarization antenna with high cross-polarization discrimination(XPD) that can improve the capacity of a small cell using a dual polarization multiple antenna (MIMO). By using the symmetric structure and differential feeding, high XPD in all directions is achieved. In addition, a very similar radiation pattern is observed between each polarization. Because of high XPD and similar radiation pattern in all directions, proposed antenna is well adopted for small-cell multiple-input multiple-output(MIMO) system. Experimental results shows that the proposed antenna has a bandwidth of 180 MHz (2.51~2.7 GHz), a maximum gain of 4.5 dBi (3.5~4.5 dBi), and a half-power beam width of 85 degrees. In addition, average XPD of 26.4 dB in all directions, more than 13.8 dB increase than previous dual-polarization antennas which use single emitter by using different feeding or selectively use polarization through switching.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.7
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• pp.1537-1543
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• 2010

This paper describes a compact microstrip antenna with dual polarization characteristics. The antenna, receiving both a left-hand circularly polarized(LHCP) wave and a right-hand circularly polarized(RHCP) wave, can be used for a polarization diversity. A diamond-shaped patch with internal empty room is designed for impedance matching as well as size reduction. And slots are added around feeding point to improve input matching. The proposed antenna has been applied to GPS(global positioning system), operating at 1.57GHz. And, the proposed idea has been verified and estimated by simulation. The measurement results show that it has VSWR 2:1 bandwidth of 83MHz, 3dB axial bandwidth of about 58MHz, 3dB beamwidth of 90degree, and gain of 0dBi, respectively, for RHCP. Also, it has similar performances for LHCP.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.7
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• pp.606-612
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• 2015

This paper proposes a new design of a dual-band orthogonal-polarization microstrip antenna for V2N(Vehicle to Nomadic Device) communication system. The proposed antenna consists of a perpendicular feeding structure for utilizing orthogonal linear polarizations and an microstrip radiator which loaded by close-looped H-shape slot for obtaining dual-band operation. Due to the geometrically different loading effect of the close-looped H-shape slot for each feeding location, the orthogonally linear polarization at dual-band operation of the proposed antenna can be successfully achieved. The proposed antenna theoretically and experimentally demonstrates the vertical linear polarization at the operating frequency of 1.8 GHz and the horizontal linear polarization at the operating frequency of 2.4 GHz, respectively. The simulation and measurement results of the implemented antenna have been in good agreement with the reflection coefficients, radiation patterns, and realized antenna gains.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.7
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• pp.823-830
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• 2010

This paper deals with a coaxial-to-waveguide transition generating circularly polarized wave to be connected with horn antennas. By combining vertical coaxial fed structure, back-short and the polarization twisting structure, the circular polarization is successfully generated in the waveguide. The designed and implemented transition shows that the present structure can significantly reduce the size of the antenna part at X-band.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.49 no.3
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• pp.47-52
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• 2012

This paper is in regard to design and experiment about the radar's circular polarization antenna operating in the Ku band. By using the Post to manufacture the circular polarization antenna using the linear antenna, it could reduce the structural size of an antenna. 3 Posts were used in order to broaden the Axial ration Bandwidth of the circular polarization antenna. The distance and length between Posts and Post were appropriately selected for the axial ratio optimization and applied in the design. It was verified that the designed antenna has the impedence bandwidth of 12.7%, axial ratio performance less than 2dB and gain of 7.8dBi.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.3
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• pp.379-387
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• 2000

In this paper, to transmit and receive the differently polarized wideband signals simultaneously with a single antenna system, the wideband, dual-frequency and dual-polarized(WDFDP) microstrip array antenna is proposed and designed. This antenna operates simultaneously at 14.25 GHz and 12.50 GHz. To extend to two dimensional array, microstrip feed line and coaxial probe through via-hole are used. The experimental results show that the proposed WDFDP microstrip antenna can be used in the compact portable terminals with a single antenna system and the characteristic of the resonators in this antenna produces a greatly enhanced bandwidth.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.9A
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• pp.2391-2401
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• 1998

An L-band (1435-MHz~1535MHz) omnidirectional circular polarized wave antenna is designed and evaluated for transmitting/receiving of vehicle data. Conventioanl linear polarized wave antenna can not receive clearly all of the vehicle data which come from the wide driving test range on account of distortion. To vercome this problem, an omnidirectional circular polarized wave antenna is reuaried an designed. For the design, first of all, the charcteristics, design principle and theoretical background of circular polarized wav ewith a little signal loss ahve been reviewed. The characteristics of th edesigned antenna are analyzed wave with a little signal loss have been reviewed. The characteristics of the designed antenna is increased over 5dB comparing to that of linear polarized wave. Our results also demonstrate that the strength of vehicle data is flat enough over the full test range using this new antenna.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.05a
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• pp.234-237
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• 2002

A microstrip patch antenna with circular polarization based on the Sierpinski fractal is composed of 3 equilaterial triangular Polarization by sequentially rotation techniques. The characteristics of a $1\times3$ antenna array from Sierpinski geometry an investigated, i.e. port isolation and AR(axial Ratio).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.11
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• pp.3137-3143
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• 2009

In this paper, a single arm spiral antenna has been investigated about the characteristics of polarization and tilt beam. If a circumference length of spiral is bigger than a wavelength, it have a characteristic of varying maximum radiation beam direction. In addition, circular polarizations (RHCP, LHCP) can be variable by the feeding points (inner, outer). Also maximum beam directions tilt in different direction according to the circular polarizations, LHCP and RHCP. These characteristics of single arm spiral antenna are able to apply in the beam forming, diversity, MIMO application which has dual polarization using an antenna element.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2001.11a
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• pp.161-164
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• 2001

본 논문에서는 주어진 주파수대역에서 우수한 원편파 특성을 가지고 광대역에서 저반사 손실을 가지는 이종대역 안테나 피드용 원형도파관 유전체 편파기의 설계기법을 제시하였다. 양호한 편파특성을 위한 유전체판 두께와 원형 도판관 직경의 결정방법을 제시하였다. 또한 이종 대역 안테나 피드용으로 광대역에서 저반사 손실을 가지기 위한 유전체 형상 설계기법을 제시하였다.