• Journal of Electrical Engineering and Technology
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• v.9 no.4
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• pp.1365-1368
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• 2014

A CPW-fed to CPS dipole antenna of triangular loop director by microstrip tapered balun is proposed for dual and wide band operations, in this paper. The proposed antenna is consisted of a CPW-fed to CPS transform, microstrip tapered balun element, CPS dipole driver and triangular loop director. A dual and wide bandwidth of the proposed dipole antenna is realized by introducing the triangular loop director and taper matching element. The operated frequency bandwidth is 1GHz (2.14~3.14 GHz) and 1.9 GHz (4.6~6.5 GHz) to return loss criterion of less than 10 dB. The measured return loss of the proposed antenna showed good results of the dual and wide band operating frequency and the radiation pattern. The proposed antenna is able to support WLAN wireless communications applications.

• Journal of information and communication convergence engineering
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• v.14 no.4
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• pp.222-226
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• 2016

A design method for a compact square loop antenna fed by a microstrip (MS) line for indoor digital television (DTV) applications is proposed. The proposed antenna consists of a square loop, circular sectors, and an MS line. The square loop combined with circular sectors is printed on one side of a substrate, and a $75-{\Omega}$ MS line is printed on the other side. The circular sectors are used as a wideband balun or transition to connect the MS line and the square loop. A prototype of the proposed square loop antenna operating in the DTV band (470-806 MHz) is designed and fabricated on an FR4 substrate. Experimental results show that the proposed antenna has the desired impedance characteristics in the frequency band of 464-1,220 MHz (89.8%) for a voltage standing wave ratio (VSWR) of <2 covering the DTV band, and a broadside gain of 0.8-3.3 dBi in the DTV band.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.61 no.1
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• pp.1-4
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• 2012

In this paper, the planar type modified folded loop antennas for S-DMB band is proposed. The proposed antenna consisted of opened center of a conventional closed loop and folded terminal of microstrip line to inside loop antenna. The sizes proposed antenna was minimized by folding the terminal of the loop. Also, It was minimized reactance value by increasing capacitances between coupled microstrip line. Therefore the proposed antennas compacted about 20% than a conventional loop antenna and increased efficiency of antenna. The proposed antennas got an omni-directional pattern, the antenna gain was 3.67 [dBi] and the bandwidth was 900 MHz (2.6-3.56 GHz) with VSWR${\leq}$2 from the simulated and the measured results. The frequency utilization coefficient was 29.9 %. These properties could satisfy the S-DMB band.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.8
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• pp.921-926
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• 2014

In this paper, the characteristics of inset fed microstrip antenna loaded with CSLR(complementary single loop resonator) are studied. Effective permeability parameters of the SLR unit cell is retrieved from simulated scattering parameters, and structure parameters of the SLR unit cell are selected so that effective permeability is negative value at the operating frequency. The optimized inset fed microstrip antenna loaded with SLR for a $3{\times}3$ array in the ground plane of a conventional patch antenna is designed and simulation results of return loss and radiation pattern are shown. At resonant frequency 2.82 GHz, the overall dimension of the proposed antenna is reduced by approximately 56.8% compared to the conventional inset fed antenna. Simulation results are obtained by 3D FEM solver(Ansoft's HFSS).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5447-5451
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• 2012

This paper presents a pattern-switchable microstrip patch antenna with loop structure. The loop structure for switchable radiation beam pattern is connected with feeding line of the microstrip patch antenna. As changing switch on/off state, the radiation beam pattern can be changed. The target frequency is 2.4 GHz and maximum radiation gain is 3.2dBi. The proposed antenna is useful for diversity antenna and smart antenna in modern wireless communication including MIMO (Multi-Input Multi-Output) and WLAN system. The sizes of the rectangular patch and the ground plane are $28mm{\times}28mm$ and $40mm{\times}50mm$, respectively. The simulation and experimental results show that the antenna radiation pattern can be changed with switch on/off configuration.

• Journal of information and communication convergence engineering
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• v.8 no.5
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• pp.489-492
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• 2010

This paper proposes the planar-type modified monopole antennas of loop structure. This antenna has an opened center of a conventional closed loop structure with an inside-folded terminal of the loop microstrip line. The size of the proposed antenna was minimized by folding the end of the loop. Also, the reactance value has been minimized by increasing capacitances between the coupled microstrip line. Therefore the proposed antenna has been compacted to about 20% from a conventional loop antenna and has increased its efficiency. The proposed antennas have an omni-directional pattern, the antenna gain was 3.67 [dBi] and the bandwidth was 900 MHz (2.6~3.56 GHz) with VSWR$\leq$2 from the simulated and the measured results. The frequency utilization coefficient was 29.9%. These properties could satisfy the S-DMB band.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.637-640
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• 2006

In this paper, a microstrip antenna with a small loop consisting of the left and right parallel plate to load capacitor is proposed. It is obtained the improved small size than the antenna of the transformed Uh and the antenna of the left and right parallel plate to load capacitor on QMSA. Equivalent circuit of transmission line model is designed to find more accurate resonant frequency. Also, the designed and fabricated antenna can receive both vertically and horizontally polarized waves to operating frequency of 1.5GHz. Therefore proposed antenna is available as a small antenna for wireless communication and will be quite useful for indoor communication

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.61 no.1
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• pp.5-9
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• 2012

In this paper, multi folded dual monopole antenna for WLAN communication of dual bend is designed and fabricated. The proposed multi folded dual monopole antenna are consisted of two folded rectangle loops by microstrip fed that is modified dual monopole antenna. Therefore, the outside rectangle loop structure of the proposed antenna is extended a dual monopole. The characteristics of the proposed antenna is analyzed return loss and radiation patterns by the FDTD tools. As a result a bandwidth of proposed antenna has about 0.82GHz from 2.0 to 2.82[GHz] and 0.7GHz from 5.46 to 6.16[GHz]. It is used WLAN communications of 2[GHz] and 5[GHz].

• Journal of electromagnetic engineering and science
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• v.18 no.2
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• pp.129-135
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• 2018

This paper proposes a design of small controlled reception pattern antenna (CRPA) arrays using circular microstrip loops with frequency-insensitive characteristics. The proposed array consists of seven identical upper and lower circular loops that are electromagnetically coupled, which results in a frequency-insensitive behavior. To demonstrate the feasibility of the proposed feeding mechanism, the proposed array is fabricated, and its antenna characteristics are measured in a full-anechoic chamber. The operating principle of the proposed feeding mechanism is then interpreted using an equivalent circuit model, and the effectiveness of the circular loop shape is demonstrated by calculating near electromagnetic fields in proximity to the radiator. The results confirm that the proposed feeding mechanism is suitable to have frequency-insensitive behavior and induces strong electric and magnetic field strengths for higher radiation gain in extremely small antenna arrays.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.7 no.2
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• pp.139-146
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• 1996

In this paper, the total electric field antenna in the small loop and aperture plane structure to load a capacitance on transformed QMSA(Quarter-wavelength Microstrip Antenna) from MSA(Microstrip Antenna) is proposed, and the total electric field is shown that the calculated value is agreed resonably with experimental value. Itis a smalled antenna of the radiation element and ground plane with equal width. The designed and manufactured antenna can receive borth vertically and horizontally polarised waves to operating frequency of 1.5GHz; therefore this is available as a smalled antenna for wireless telephones and will be quit useful for indoor communication. Also, antenna's equivalent circuit with transmission line model is designed to find more accurate resonant frequency and is calculated return loss value. The calculated value is agreed resonably with experimental value.