• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.5
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• pp.849-856
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• 2020

The Angle-of-Arrival(AOA) information for an array antenna receiver is one of the important factors for estimating the location of specific signals and detecting signals efficiently, in various situations. The AOA estimator in the satellite environment can rapidly calculate the AOA information in the wide area, utilizing a planar (grid, circular) array antenna mounted on the satellite. Since the satellite receiver has the limitation of the array antenna size, the concentric circular (ring) array (CCA or CRA) antenna structure with comparatively small size but with multiple antenna elements is more efficient than the uniform circular array (UCA) structure, for the satellite environment. In this paper, we introduce a cascade AOA estimation algorithm based on CRA, consisting of CAPON and Beamspace MUSIC. In addition, we provide computer simulation examples for verifying the estimation performance of the cascade AOA estimation algorithm based on CRA and compare it to the case of UCA.

• Aerospace Engineering and Technology
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• v.6 no.2
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• pp.52-59
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• 2007

Telecommunication satellite consists of a bus system and an RF payload system with high efficiency and high gain reflector antennas. Antenna measurement and also RF system performance (antenna under test, payload and satellite level) have to be evaluated enough before launching in the far-field range or equivalent test range. Basically far-field range is required in a range from two hundred meters to several kilo meters, and it is highly constrained to the externa1 environment, like the RF and the whether environment So the compact antenna test range is developed and used efficiently without external environments as in-door facility. This paper describes the configuration of the compact antenna test range, the range error, and the physical concept of the plane wave illumination Also, it provides a overall design of the anechoic chamber and range parameter values to accommodate the precision measurements in antenna test range.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.11 s.114
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• pp.1082-1088
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• 2006

A turnstile antenna using the parasitic monopole has been developed for STSAT-2 TT&C application. The antenna consists of two radiating elements; a bow-tie dipole and a parasitic monopole. The bow-tie dipole is main radiating element, used a bow-tie structure for bandwidth improvement and size reduction. The parasitic monopole improved beamwidth and axial ratio. The input impedance of the antenna is about 50 ohm without a matching circuit. The proposed antenna has beamwidth of $>140^{\circ}$, axial ratio of < 3 dB and VSWR of < 1.5 in the band of $2.075{\sim}2.282GHz$.

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.180.1-180.1
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• 2005

• Journal of the Korea Institute of Information and Communication Engineering
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• v.2 no.4
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• pp.539-544
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• 1998

This paper presents the stabilization of a shipboard satellite antenna system. Hardware systems composing the pedestal, pedestal control unit and antenna control unit are designed and stabilization control law is obtained. A model on each control axis is derived and its parameters are estimated using a genetic algorithm, and the optimal state controller is designed based on the estimated model. An experimental result demonstrates the effectiveness of the proposed system.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.10a
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• pp.294-297
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• 2003

In this paper we designed and measured HTS antenna array for Direct Broadcast Satellite (DBS) system. HTS antennas fabricated in this work were a four-element, 11.67 ㎓z, high-Tc superconducting (HTS) microstrip antenna array with corporate feed network and circular polarization for direct broadcas- ting satellite (DBS) system. Our antennas was designed and built on a 0.5 mm thick YBa2Cu3O7-x (YBCO) /MgO substrate. The measurement results showed good axial ratio, wide bandwidth a remarkable improvement over their metal counterpart.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.60 no.4
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• pp.167-171
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• 2011

In this paper, $2{\times}4$ microstrip patch antenna are proposed to implement K-band satellite communications. The microstrip feed line are inset into the radiation patch to match input impedance. Also the same current in each elements are excited by Kirchhoff's low. The elements distance of proposed array antenna are optimized $0.8{\lambda}_g$ to minimize a mutual coupling and maximize a gain. A power divider network are employed to distribute T-junction divider. As result, the proposed antenna get gain of 14[dBi] at 10.525[GHz].

• Journal of Satellite, Information and Communications
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• v.11 no.1
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• pp.37-40
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• 2016

We designed an antenna structure with the circular polarization metamaterial superstrate which increases the directivity of the primary antenna as a lens. The metamaterial superstrate removes the necessity of the array antenna and complicated feed. Plus, it provides the Fabry-perot cavity with the circular polarization. With regard to the primary antenna, a CRLH antenna is adopted to have the size-reduction from the conventional half-wavelength patch antenna.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.9
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• pp.2514-2525
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• 1996

This paper presents the possibility of the satellite broadcasting reception as a means of microstrip antenna of the planar structure. The paper discusses the design of the optimal KOREASAT DBS(Direct Broadcasting Satellite) reception microstrip antenna. Experimental results for ta 16*16 array antenna of size 35*35cm are also described. Itsgain is over 28dB in the frequency range of 11.7~12.0GHz DBS band. The measured NHK broadcasting C/N ratio of 16816 array antenna is over 10dB in Pusan. It is expected that good picture quality of C/N .GEQ. 12dB can be obtained for domestic use if this microstrip antenna is used in KOREASAT broadcasting receiving system.

• Journal of Positioning, Navigation, and Timing
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• v.13 no.3
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• pp.277-287
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• 2024

In satellite systems, efficient communication and observation require identifying of specific signal arrival points using onboard antenna systems. When utilizing massive array antennas to estimate the angle of arrival (AOA) of signals, traditional high-performance AOA estimation algorithms such as Multiple Signal Classification (MUSIC) encounter extremely high complexity due to the numerous individual antenna elements. Although, in order to improve this computational complexity problem, the cascade AOA estimation algorithm with CAPON and beamspace-MUSIC was recently proposed, the comparison of the computational complexity of the proposed algorithm across different massive array antenna configurations has not yet been conducted. In this paper, we provide the analyzed results of the computational complexity of the proposed cascade algorithm based on various massive array antennas, and determine an optimal antenna configuration for the efficient AOA estimation in satellite systems.