• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.9A
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• pp.906-912
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• 2006

In this paper, N-shaped slot antenna for $5.15GHz{\sim}5.35GHz$ is designed, fabricated, and measured. The prototype consist of meander corrugated N-shaped slot. To obtain suitable bandwidth, the form layer is inserted between ground plane and substrate. Important parameters in the design are N-slot length, width, position, air-gap height, and feed point position. From these parameters optimized, a four N-shaped slot antenna is fabricated and measured. The measured results of the antenna are obtained as follows results. The resonant frequency of the fabrication N-shaped slot antenna is 5.25GHz bandwidth for approximately 300MHz(VSWR<2.0) and the gain is $1.3{\sim}2.64dBi$. The experimental far-field patterns are stable across the pass band. The 3dB bandwidth in H-Plane and E-Plane are $80.21^{\circ}\;and\;103.38^{\circ}$, respectively.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.12
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• pp.2816-2822
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• 2014

In this paper, a wideband loop antenna for UWB applications is studied. The structure of the proposed wideband loop antenna is a circular loop antenna with appended circular sectors to obtain an ultra-wideband characteristic. The circular sectors are used instead of conventional triangular sectors to match with the 50 ohm feed line. Optimal design parameters are obtained by analyzing the effects of the gap between the circular sectors and the radius of the circular loop on the input reflection coefficient and gain characteristics. The optimized wideband loop antenna is fabricated on an FR4 substrate with a dimension of 41 mm by 41 mm. Experiment results show that the proposed antenna has a frequency band of 3.1-11.0 GHz for a VSWR < 2.25, which assures the operation in the UWB band. Measured gain ranges 1.3-5.3 dBi in the UWB band.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.1 s.116
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• pp.82-89
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• 2007

This paper presents a coplanar waveguide fed L-planar type monopole antenna which covers ultra wideband(UWB) region of 3.1 GHz to 10.6 GHz. The proposed UWB L-planar type monopole antenna is designed and implemented on the organic substrates( ${\varepsilon}_{r}=3.38,\;@10\;GHz$). The radiation elements, feed line, and ground planes of the antenna are printed on the same conductive layer of the substrates. The bandwidth of the proposed antenna is measured in the range of 3.0 GHz to 11.0 GHz. The measured radiation patterns are symmetrical in E-plane and omni-directional in H-plane. Antenna gains ranges from 1.4 dBi to 4.6 dBi. The proposed UWB antenna shows that the structure is adequate for the design of RFIC.

• The Journal of the Korea institute of electronic communication sciences
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• v.19 no.1
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• pp.11-18
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• 2024

This paper presents a procedure to optimize the design of 70GHz band array antenna for automotive short range radar sensor applications using Chebyshev polynomials. SRR(: Short Range Radar) systems require a wide angle width and low Side lobe level to detect targets within close proximity while ensuring a high Field of View(FoV). The optimized antenna operates in the 76 to 81GHz frequency range, and to reduce the antenna size, we arranged 12 patches in series, achieving an SLL of 10dB, angle with of 112.5o, gain of 15.4dB and an input return loss of less than -10dB at 78GHz. In this paper, we proceed with antenna design for SRR using Chebyshev polynomials, and present an optimal design for antenna structures to be used in MRR(: Medium-Range Radar) and LRR(: Long Range Radar) applications based on this paper

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.11
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• pp.77-84
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• 2003

This paper presents a multi-functional microstrip spital antenna that operates in dual frequency bands. Several types of beam shape can be selected by controlling the phase difference of two spiral arms with the phase shifters located on each feed line. It has a normal beam at the lower frequency band, and four different patterns at the higher frequency band: normal beam, conical beam and two types of tilted beam. The antenna exhibits more than 10% of bandwidth at each band. The antenna is fabricated with conductor backed electromagnetic absorber in order to attain unidirectional radiation pattern and confirmed the multi-functionality by measurements.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.9
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• pp.851-857
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• 2002

A two-arm microstrip spiral antenna with a circular aperture on the ground plane that generates a circularly polarized conical beam is presented in this paper. We obtained circularly polarized conical beam by using two spirals that are excited in-phase from the microstrip feed lines. The main beam directions of the conical beam from the broadside are approximately 40$^{\circ}$ in the range from 5 GHz to 6.5 GHz, and 58$^{\circ}$ from 9 GHz to 11 GHz. Since the proposed antenna has omni-directional conical beam pattern, it is suitable for use in mobile communication systems.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.1
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• pp.32-43
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• 1999

In this paper, the transformed QMSA to load a capacitor without limitation of the electric force on QMSA(Quarter-wavelength Microstrip Antenna) is designed. Bandwidth of the designed and manufactured antenna is 5.7% at the resonant frequency of 2.0 GHz and the resonant frequency and bandwidth versus change of any arbitrary feed point is observed. Since the size of wide slot width between the left and right parallel plate to load a capacitor is very wide bandwidth, will be suitable for very wide bandwidth communication. The radiation pattern characteristics of the designed antenna based on the dipole structure and the aperture structure analysis method. As calculation results, relative backward radation is - 5 dB.

• Journal of Korea Society of Industrial Information Systems
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• v.6 no.4
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• pp.6-11
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• 2001

In this paper, the aperture-coupled U-slot microstrip patch antenna is studied for the bandwidth improvement. The aperture is used as a mechanism for coupling the radiating element to the microstrip feedline, and the aperture-coupled configuration provides the advantage of isolating spurious feed radiation by the use of common ground plane. Experimental results such as return loss, VSWR, radiation pattern and gain measurements are presented on the aperture-coupled U-slot microstrip patch antenna. The impedance bandwidth (VSWR≤2) of the antenna is 6.4% centered at 2.35GHz, and the average gain is 5.3 dBi.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.7
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• pp.1057-1066
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• 2001

This paper describes a design for linear polarization antenna using the EMCD (electromagnetically coupled dipole). The analysis and the design of model antennas are conducted by FDTD method. Vertical and horizontal linear polarizations are easily obtained by variation of dipole position. In 1-element antenna design, mutual coupling between microstrip feed line and radiator is considered. Design parameters of each 1-element antenna with vertical and horizontal polarization are used for array design. Radiation power and main beam tilting angle can be controlled by the offset and the distance between radiating elements in an array, respectively. 5-element array antennas are fabricated and measured to prove the design validity. The results of FDTD simulation and measurement show the reasonable agreement.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.2
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• pp.386-391
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• 2006

In this paper, a design of V-type Linearly Tapered Slot Antenna(V-LTSA) with uniplanar microstrip-to-coplanar stripline(CPS) transitions is presented. The effect of reducing and increasing with taper width G, teper length L and opening angle are also considered at 5.8 GHz. In the result of a simulation by using CST-MWS, the return loss characteristic came very wide band about 4.3GHz, or 1.8 Octave. Proposed V-LTSA design schemes are expected to be a good antenna for microwave and millimeter-wave communcations.