• ETRI Journal
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• v.29 no.6
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• pp.725-735
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• 2007

This paper describes a line element planar antenna with three frequency bands. To obtain broadband characteristics, a modified planar antenna that has semi-elliptical elements based on the characteristics of a line element planar antenna is proposed and analyzed by the finite difference time domain method. Return loss characteristics are discussed as functions of the eccentricity values of semi-ellipse at each element. The broadbanding of the modified planar antenna is implemented based on the results. The planar antenna with three systems (an 800 MHz band cellular phone, a third-generation cellular phone, and a 2.4 GHz band wireless LAN system) is considered as an application example.

• Journal of electromagnetic engineering and science
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• v.5 no.1
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• pp.14-20
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• 2005

In this paper, a technique is presented for broadbanding the bow-tie slot antenna fed by a CPW(coplanar waveguide). The bandwidth performance of existing bow-tie slot designs is greatly enhanced by optimizing the slot shape and properly adjusting the characteristic impedance of the coplanar waveguide feeding the slot. To connect the 50-ohm input coaxial line to the CPW feed line, a linear taper in the CPW is employed. The designed antenna shows a 3.5 $\~$ 10.0 GHz impedance bandwidth, a 3.5 $\~$ 6.0 GHz pattern bandwidth, and a 5.5 $\~$ 7.5 dBi gain over 3.5 $\~$ 6.0 GHz. Above 6.0 GHz, the antenna radiation pattern appreciably deviates from the typical dipolar pattern.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.4
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• pp.983-990
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• 2010

In this paper, we designed and implemented the MIMO antenna for LTE(Long Term Evolution), supposed to be a next generation communications network, DCS1800, DCS1900 and WCDMA. Using conventional monopole antenna with MD material results in good characteristics, miniaturization for LTE band and as well as broadbanding for DCS, WCDMA band. The performance of the proposed MIMO antenna shows VSWR < 2, under -10 dB of isolation and the gain is -1.66 ~ 1.33 dBi for LTE(Long Term Evolution), DCS1800, DCS1900 and WCDMA, which has omnidirectional radiation pattern.

• Journal of Korean Library and Information Science Society
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• v.37 no.4
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• pp.351-370
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• 2006

The goal of this study was to evaluate vision, mission, strategies, and action plans from the long-term development plan for the B University's library, and specificity, measurability, achievability, relevance, and time-frame were measured and evaluated for each with SMART method. The results obtained through this study are as below : Firstly, SMART evaluation result for the B University's library was 3.80 for the vision, 3.97 for the mission, 3.74 for strategies, and 3.64 for action plans. Secondly, specificity of the long-term development plan for the B University's library was 4.06, measurability was 3.72, achievability was 3.68, relevance was 3.90, and time-frame was 3.58. Thirdly, the overall evaluation of the long-term development plan for the B University's library showed that among components from the development plan, the mission was the most superior while action plans had problems. Fourthly, in SMART evaluation factors, specificity was the most superior while time-frame had problems such that it should be supplemented in the future.