• Title/Summary/Keyword: multi-beam

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A Study on the Ka-Band Satellite Output Power Control Technology (Ka 대역 위성 출력 전력 제어 기술 연구)

  • Shin, Dong-Hwan;Yun, So-Hyeun;Moon, Seong-Mo;Lee, Hong-Yeol;Eom, Man-Seok;Yom, In-Bok
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37B no.11
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    • pp.1072-1081
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    • 2012
  • For Ka-band satellite communication system, a new flexible payload technologies which can compensate rain attenuation have to be developed. The Ka-band satellite output power control technology enables to adjust downlink output power of satellite payload in Ka-band (19.8 ~ 22.2 GHz). In this paper, we introduce multi-beam antenna with multi-port amplifiers for Ka-band flexible output power allocation system. We have designed multi-beam antenna with array-fed reflector to form 8 beams on the Korean Peninsula. The target EIRP per beam is more than 59 dBW. The system is designed to present 6 dB boost beams for rainfall areas. Individual beams were optimized by the excited amplitude and phase of feed elements of the feed cluster. The multi-port amplifier(MPA) is one of effective approaches for flexible power allocation in combination with multi-beam antenna. In case of using MPA in multi-beam system, the inter-port isolation characteristic of MPA is important parameter to avoid interference among the output ports. In this paper, we propose a new MPA structure that consists of two $4{\times}4$ Buttler matrixes and phase/amplitude controllable power amplifier modules.

A Study on the Operation of Multi-Beam Antenna for Airborne Relay UAV considering the Characteristics of Aircraft (비행체의 특징을 고려한 공중중계 무인기 다중빔 안테나 운용 방안)

  • Park, Sangjun;Lee, Wonwoo;Kim, Yongchul;Kim, Junseob;Jo, Ohyun
    • Journal of Convergence for Information Technology
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    • v.11 no.4
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    • pp.26-34
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    • 2021
  • In the era of the Fourth Industrial Revolution, the future battlefield will carry out multi-area operations with hyper-connected, high-speed and mobile systems. In order to prepare for changes in the future, the Korean military intends to develop various weapons systems and form a multi-layer tactical network to support On The Move communication. However, current tactical networks are limited in support of On The Move communications. In other words, the operation of multi-beam antennas is necessary to efficiently construct a multi-layer tactical network in future warfare. Therefore, in this paper, we look at the need for multi-beam antennas through the operational scenario of a multi-layer tactical network. In addition, based on development consideration factors, features of rotary-wing and fixed-wing aircraft, we present the location and operation of airborne relay drone installations of multi-beam antennas.

Research Trends in Efficient Transmission Techniques Based on DVB-S2x Standard for Multi-beam HTS and Beam Hopping Satellite System (DVB-S2x 표준기반 다중빔 위성 전송기술 동향)

  • Kim, P.;Ryu, J.G.;Oh, D.G.;Yom, I.B.;Lee, H.J.
    • Electronics and Telecommunications Trends
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    • v.33 no.3
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    • pp.34-40
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    • 2018
  • Current studies based on the DVB-S2x standard for the next-generation multi-beam HTS/BH satellite have been investigated. To enhance the efficiency of the transmission throughput and maximize the utilization of the satellite payload resources and bandwidth, the concepts of two advanced techniques, namely, precoding and BH, are described. Furthermore, state-of-the-art aspects currently under discussion, and future study items in the DVB TM-S standardization group, are summarized in this article.

Beam Rotator of Optical System Based on Multi-Beam (다중 광선을 이용한 광 시스템의 광선 회전기)

  • 이정현;한창수;김수현;곽윤근
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.12
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    • pp.194-201
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    • 1998
  • The beam rotating actuator has been developed. It can be utilized to improve the data transfer rate for the optical disk systems, Newly developed laser beam rotating actuator is applied to put multi-beam spots on more than one track on the optical disk simultaneously. The beam rotating actuator is made of piezoelectric ceramic bimorph as the form of cantilever, Piezoelectric actuators with high resolution, high stiffness and fast frequency response are widely assembled in micropositioning applications. Therefore, the actuator has above 50Hz natural frequency. Beam array is rotated using the dove prism in the end of beamrotator. The dynamic equation of beam rotating actuator is derived theoretically. The actuator is designed on the ground of this analysis. The performance of the beam rotating actuator is verified as the dynamics frequency performance is measured using the dynamic analyzer and sensor.

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Operating System Design of Multi Beam Control System with Miniaturized Electron Beam Columns (초소형 전자빔을 이용한 멀티 전자빔 운영 시스템 설계)

  • Lim, Sun Jong;Kim, Ho Seob
    • Laser Solutions
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    • v.18 no.4
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    • pp.12-16
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    • 2015
  • The research on multi electron beam systems is being carried out by various methods. We are studying multi electron beam system using miniaturized electron beam columns. The column consists of electrostatic lenses, electrostatic deflector and tip emitter. Our operating system controls 4 column array, captures images of each column and maintains the instrument. We present the usefulness of our operating system for multi columns by capturing images of each column.

Implementation of Multi-Beam Pattern Compact MIMO Antenna based on Switched Parasitic Antenna (SPA 기반 다중 빔 패턴 고집적 안테나 개발)

  • Yoon, Sang-Ok
    • The Journal of the Korea institute of electronic communication sciences
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    • v.15 no.2
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    • pp.219-224
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    • 2020
  • In this paper, we studied the compact MIMO(: Multi-Input Multi-Output) antenna for multi-beam pattern generation and control in narrow space. The characteristics and performance of the basic Dipole SPA and Monopole SPA structures are shown. We implemented a monopole SPA antenna and measured its performance in an 802.11g system. When the average transmission rate was measured using the SPA antenna, the SPA antenna improved the best performance by 8.7 times compared to commercial antenna.

Frequency Sharing between Multi-beam Mobile Satellite Communication System and Mobile Communication System in 2.1 GHz Band (2.1 GHz 대역 다중빔 이동위성통신 시스템과 이동통신 시스템간 주파수 공유)

  • Jeong, Nam-Ho;Kim, Hee-Wook;Oh, Dae-Sub;Ku, Bon-Jun
    • Journal of Satellite, Information and Communications
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    • v.7 no.1
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    • pp.102-107
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    • 2012
  • In this paper, we presented interference scenarios and an evaluation methodology for the co-frequency radio interference between a multi-beam mobile satellite communication system and a mobile communication system in 2.1 GHz band. Radio interferences between these systems are calculated using a minimum coupling loss method and an assesment for minimum separation distances was conducted for coexistence of a mobile satellite system and a mobile system in the same geographical area.

The Development of Beam Rotating Actuator for High Speed Optical Disk Storage (고속 광학기록매체용 다중빔 회전 구동기의 개발)

  • 김병준;김수현;곽윤근
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1997.10a
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    • pp.1072-1075
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    • 1997
  • To enhance the effective data transfer rate the multi-beam optical disk drive is presented. The Beam rotating actuator is necessary for putting multi-beam on more than one track. Ray tracing was also executed for real system set-up. The Beam Rotating Actuator is made up of piezoelectric material, high stiffness wire hinge and dove prism. The actuator has about 1kHz natural frequency and suitable and suitable operational range. The dynamic equation for the actuator is derived for the control of real system.

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