• Journal of Advanced Navigation Technology
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• v.21 no.5
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• pp.466-471
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• 2017

SOTM is a device for the satellite communication on the move. Many studies are conducted on microstrip, waveguide and array antenna for the low profile of the SOTM's antenna. But those antennas have a problem that is difficult to adjust the polarization, and for that reason we have studied the parabolic antenna structure. The general form of parabolic reflector structure is circular, but we used cut-off shape reflector by cutting the upper and lower reflector for low profile antenna. Accordingly, this results in the decrease of reflector area which causes reduced gain and G/T ratio. In order to solve this problem, we have transformed and designed the sub reflector for improving the efficiency and gain of the cut- off shape parabolic antenna.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.4 no.1 s.6
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• pp.89-95
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• 2005

In this paper, a quad-band antenna for GSM/GPS/DCS/US-PCS handsets is proposed. The proposed antenna is low-profile for mounting in limited inner space of a handset. It consists of three open points with quarter wave length for multi-band operation. The ground plane below the patch is removed for wide-bandwidth without the variation of antenna size and the slot is added at the center of the patch for convenient matching in high frequency band. It provides a enough bandwidth within VSWR 3:1 at all bands. In addition, the measured peak gains are between -2.19 and 2.09 in anechoic chamber (10m$\times$6m$\times$4m).

• Journal of electromagnetic engineering and science
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• v.18 no.4
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• pp.261-266
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• 2018

This paper reports on the proposed design of a low profile broadband array antenna for home repeater applications. The proposed antenna consists of $1{\times}4$ patch elements and two ground planes, one of which is slitted. By using the gap feeding method, the impedance matching of the antenna is improved by a multi-resonance phenomenon. The proposed antenna provides a wide -10 dB reflection coefficient bandwidth simultaneously covering the Global System for Mobile communications (GSM-1800), Personal Communications Service (PCS), and the Universal Mobile Telecommunication System (UMTS) bands (1.67-2.32 GHz). In order to reduce the mutual coupling between adjacent patch elements, slits are embedded in the ground plane. An isolation level of -20 dB is realized over the entire operating frequency band.

• Journal of Satellite, Information and Communications
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• v.12 no.1
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• pp.94-100
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• 2017

In this paper, we suggest a design method of a metamaterial-based low-profile antenna working at 425 MHz for LEO/Cube satellites. Satellites play an important role in linking th remote nodes in a wireless communication network and covering wide areas of the globe. Especially, an increasing number of universities or individuals aspire having their own satellites and build low-budget structures such as cube satellites in LEO and the ways to reduce the sizes of their satellites. Since the antenna occupies a major portion of the satellite surface, the antenna should be miniaturized for lighter weight. The proposed metamaterial low-profile antenna, unlike the conventional patch antenna, produces such a zeroth-order resonance to create an omnidirectional radiation pattern. Also, it is connected to a UHF waveguide bandpass filter as the feeding system to examine the possible change in the situation that the antenna is combined with the system. The performances of the monopole and proposed metamaterial antennas are compared to one another.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.4
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• pp.165-169
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• 2011

In recent years mobile phone handset terminal has tended to have additional various functions and slim and light weight, and its internal space is getting smaller and narrower. According to complex parts, small and narrow inner space is caused not sufficient bandwidth and lower impedance. Moreover, additional polarization loss by the surrounding parts produces is lower effectiveness and increases difficulties for getting the antenna gain. For IFA is low profile structure based on the ILA(Inverted L Antenna) which is transformed from the monopole antenna. While this antenna has lots of advantages in internal antenna of mobile phone, it has some disadvantage of reduced bandwidth and gains compared with monopole antenna. In this paper, propose vlade hybrid antenna use for the coupling structure.

• Journal of IKEEE
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• v.23 no.3
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• pp.1112-1115
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• 2019

This paper proposes a novel low-profile omni-directional microstrip antenna to mount on the deployable wing of the observation munition. The proposed antenna is designed on seven hexagonal resonators in a quasi-circular array to achieve a monopolar radiation pattern with a thin substrate. By employing the mesh ground structures, the resonant frequencies and impedance bandwidths of the proposed antenna is investigated. To verify the feasibility of the mesh ground structure, the thin ground wire width is investigated theoretically for improving the 3-dB fractional bandwidth, realized antenna gain and quality-factor. The proposed antenna demonstrates a good monopolar radiation in good agreement with the simulation results. The implemented prototype shows the measured bandwidth of 326 MHz with respect to 5.65% centered at 5.77 GHz and realized gain of 5.49 dBi at 5.84 GHz.

• Journal of Satellite, Information and Communications
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• v.2 no.2
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• pp.10-15
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• 2007

Small size and low profile antenna for mobile vehicular-top-mounted is needed in satellite communication services such as DBS, Satellite Internet and VSAT. In middle latitudes, the development of an array antenna which has the conformal, low profile and 45 degree beam tilted configuration, and has the high gain with sharp beamwidth, low sidelobe and low loss is required for Ku-band satellite communication. In this paper, in order to meet with these performances, an array antenna consisting of the vertical polarized waveguide longitudinal slots based on the leaky-wave mode of traveling wave antenna is proposed. An array antenna consisting of 16 leaky-wave elements is showing 30 dBi of gain, 4.9 degree of beamwidth, below than -20 dB of sidelobe level, 45 degree of beam tilt angle in center frequency. Feed network designed by waveguide cooperated feed shows good performance of wideband and low loss.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.2 no.2
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• pp.69-77
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• 2009

Small size and low profile antenna for mobile vehicular-top-mounted is needed in satellite communication services such as DBS, Satellite Internet and VSAT. In middle latitudes, the development of an array antenna which has the conformal, low profile and 45 degree beam tilted configuration, and has the high gain with sharp beamwidth, low sidelobe and low loss is required for Ka band satellite communication. In this paper, in order to meet with these performances, an array antenna consisting of the vertical polarized waveguide longitudinal slots based on the leaky-wave mode of traveling wave antenna is proposed. Especially, for the lower sidelobe level the radiation power control using a design method of the different slot width is proposed. An array antenna consisting of 32 leakywave elements is showing 34.4 dBi of gain, 3.6 degree of beamwidth, below than -25 dB of sidelobe level, 43 degree of beam tilt angle in center frequency 20.0 GHz. Feed network designed by waveguide cooperated feed shows good performance of wideband and low loss.

• Journal of electromagnetic engineering and science
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• v.16 no.3
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• pp.194-197
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• 2016

An eight-element compact low-profile multi-input multi-output (MIMO) antenna is proposed for wireless local area network (WLAN) mobile applications. The proposed antenna consists of eight inverted-F antennas with an isolation-enhanced structure. By inserting the isolation-enhanced structure between the antenna elements, the slot and capacitor pair generates additional resonant frequency and decreases mutual coupling between the antenna elements. The overall size of the proposed antenna is only $33mm{\times}33mm$, which is integrated into an area of just $0.5{\lambda}{\times}0.5{\lambda}$. The proposed antenna meets 5-GHz WLAN standards with an operation bandwidth of 4.86 - 5.27 GHz and achieves an isolation of approximately 30 dB at 5 GHz. The simulated and measured results for the proposed antenna are presented and compared.

• 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.