• Title/Summary/Keyword: satellite component

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Launch and Early Orbit Phase Simulations by using the KOMPSAT Simulator

  • Lee, Sanguk;Park, Wan-Sik;Lee, Byoung-sun;Lee, Ho-Jin;Park, Hanjun
    • 제어로봇시스템학회:학술대회논문집
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    • 1999.10a
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    • pp.33-36
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    • 1999
  • The KOMPSAT, which is scheduled to be launched by Taurus launch vehicle in late November of 1999, will be in a sun-synchronous orbit with an altitude of 685km, eccentricity of 0.001, inclination of 98deg and local time of ascending node of 10:50 a.m. Electronics and Telecommunications Research Institute and Daewoo Heavy Industry had jointly developed a KOMPSAT Simulator as a component of the KOMPSAT Mission Control Element. The MCE had been delivered to Korea Aerospace Research Institute for the KOMPSAT ground operation. It is being used for training of KOMPSAT ground station personnel. Each of satellite subsystems and space environment were mathematically modeled in the simulator. To verify the overall function of KOMPSAT simulator, a Launch and Early Orbit Phase(LEOP) operation simulations have been performed. The simulator had been verified through various tests such as functional level test, subsystem test, interface test, system test, and acceptance test. In this paper, simulation results for LEOP operations to verify flight software adapted into simulator, satellite subsystem models and environment models are presented.

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Analysis of Adjacent Channel Interference for WCDMA ATC Service Frequency Allocation Operating in MSS Band (MSS 대역 WCDMA ATC 서비스 주파수 할당을 위한 인접 채널 간섭 분석)

  • Kang, Young-Heung;Jeong, Nam-Ho;Oh, Dae-Sub
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.23 no.11
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    • pp.1288-1296
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    • 2012
  • A candidate hybrid satellite and terrestrial network architecture, MSS/ATC(Mobile Satellite Service/Ancillary Terrestrial Component), is proposed for utilizing efficiently the exist MSS bands. Studies on the adjacent channel interference from the existing terrestrial mobile services and MSS/ATC itself are important to allocate a new ATC service frequency in MSS band. In this paper, we have analyzed the minimum permission power of terrestrial base station and the capacity loss with parameters of ACIR, number of MS(mobile Station) and MES(Mobile Earth Station) in uplink, and also, the capacity performance based on 1 beam and 1 cell assumption for MSS/ATC in downlink. The ACIR requirements are estimated in two MSS/ATC frequency allocation scenarios for 5 MHz and 10 MHz guard band to share spectrum with adjacent systems, and according to these ACIR requirements the service coverage and the receiver filter for ATC system should be designed in near future.

A Fault Detection Method of Redundant IMU Using Modified Principal Component Analysis

  • Lee, Won-Hee;Park, Chan-Gook
    • International Journal of Aeronautical and Space Sciences
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    • v.13 no.3
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    • pp.398-404
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    • 2012
  • A fault detection process is necessary for high integrity systems like satellites, missiles and aircrafts. Especially, the satellite has to be expected to detect faults autonomously because it cannot be fixed by an expert in the space. Faults can cause critical errors to the entire system and the satellite does not have sufficient computation power to operate a large scale fault management system. Thus, a fault detection method, which has less computational burden, is required. In this paper, we proposed a modified PCA (Principal Component Analysis) as a powerful fault detection method of redundant IMU (Inertial Measurement Unit). The proposed method combines PCA with the parity space approach and it is much more efficient than the others. The proposed fault detection algorithm, modified PCA, is shown to outperform fault detection through a simulation example.

Implementation of a SAR GeoCoding Module based on component

  • Kim, Kwang-Yong;Jeong, Soo;Kim, Kyung-Ok
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.337-339
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    • 2003
  • This paper describes the SAR geocoding module, which is the sub-module of a IRHIS ('Integrated RS s/w for High resolution satellite ImageS'): package of 'Development of High Resolution Satellite Image Processing Technique' project in Electronics and Telecommunications Research Institute (ETRI). The function of this module is following. 1) Orbit Type : ERS1/ERS2, RADARSAT 2) Data Format : SAR CEOS Format(Single Look Complex) 3) Function: - Geocode : Generate a map projected SAR image based on only orbit information - Orthorectify: Generate a rigorous geocoded SAR image with a DEM information In this paper, we briefly describe the algorithm that is adopted to the functions, and component architecture.

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Influence of atmospheric aerosol on satellite ocean color data in the East/Japan Sea (동해에서 대기에어로졸이 해색위성자료에 미치는 영향)

  • Yamada, Keiko;Kim, Sang-Woo
    • Proceedings of KOSOMES biannual meeting
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    • 2009.06a
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    • pp.53-54
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    • 2009
  • The influence of atmospheric aerosol on satellite ocean color data were evaluated using SeaWiFS monthly standard mapped image products. The atmospheric optical thickness (AOT) was increased in spring and summer, and it showed the strong positive correlation with remote sensing reflectance, normalized waterleaving radiance /solar irradiance, at 555 nm (Rrs555) which is a component of the satellite chlorophyll estimation. Such the high AOT and high Rrs555 pixels showed overestimation of satellite chlorophyll in spring, especially in the area which showed large phytoplankton absorption which 1s expressed by low remote sensing reflectance at 443, 490 and 510 nm (Rrs 443, Rrs490 and Rrs510).

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IMAGE DATA CHAIN ANALYSIS FOR SATELLITE CAMERA ELECTRONIC SYSTEM

  • Park, Jong-Euk;Kong, Jong-Pil;Heo, Haeng-Pal;Kim, Young-Sun;Chang, Young-Jun
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.791-793
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    • 2006
  • In the satellite camera, the incoming light source is converted to electronic analog signals by the electronic component for example CCD (Charge Coupled Device) detectors. The analog signals are amplified, biased and converted into digital signals (pixel data stream) in the video processor (A/Ds). The outputs of the A/Ds are digitally multiplexed and driven out using differential line drivers (two pairs of wires) for cross strap requirement. The MSC (Multi-Spectral Camera) in the KOMPSAT-2 which is a LEO spacecraft will be used to generate observation imagery data in two main channels. The MSC is to obtain data for high-resolution images by converting incoming light from the earth into digital stream of pixel data. The video data outputs are then MUXd, converted to 8 bit bytes, serialized and transmitted to the NUC (Non-Uniformity Correction) module by the Hotlink data transmitter. In this paper, the video data streams, the video data format, and the image data processing routine for satellite camera are described in terms of satellite camera control hardware. The advanced satellite with very high resolution requires faster and more complex image data chain than this algorithm. So, the effective change of the used image data chain and the fast video data transmission method are discussed in this paper

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Thermal Analysis of Composite Satellite Antenna Structure in Space Environment (복합재 통신위성 안테나의 우주환경 열해석)

  • ;;;;Frank Gilles
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2002.05a
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    • pp.77-80
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    • 2002
  • Thermal analysis has been performed to evaluate the thermal effect on composite antenna (Ka-band) structure in space environment. The concepts of thermal control are also presented to maintain the antenna components within respective temperature limits. A steady-state algorithm of I-DEAS' thermal analysis software was utilized to predict both maximum and minimum temperature, maximum gradient temperature, and temperature distribution on each antenna component.

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The fibronectin concentration that optimally maintains porcine satellite cells

  • Jae Ho Han;Si Won Jang;Ye Rim Kim;Hoon Jang;Kwan Seob Shim;Hyun Woo Choi
    • Animal Bioscience
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    • v.36 no.12
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    • pp.1889-1897
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    • 2023
  • Objective: 'Cultured meat' has been suggested as means of solving the problems associated with overpopulation and gas emissions. Satellite cells are a major component in the production of cultured meat; however, these cells cannot be maintained in vitro over long periods. Fibronectin is a glycoprotein that affects biological processes such as cell adhesion, differentiation, and migration. Unfortunately, the characteristics of porcine satellite cells grown in a long-term culture when exposed to fibronectin-coated dishes are unknown. The objective of this study was to investigate the appropriate concentration of fibronectin coated dishes for proliferation and maintenance of porcine satellite cells at long-term culture. Methods: In this study, we isolated the satellite cells and fibroblast cells with pre-plating method. We next analyzed the cell doubling time, cell cycle, and rate of expressed paired box 7 (Pax7) and myogenic differentiation 1 (MyoD1) in porcine satellite cells cultured with 20 ㎍/mL of fibronectin-, gelatin-, and non-coated dishes at early and late passage. We then analyzed the proliferation of porcine satellite cells with various concentrations of mixed gelatin/fibronectin. We next determined the optimal concentration of fibronectin that would encourage proliferation and maintenance of porcine satellite cells in a long-term culture. Results: Doubling time was lowest when 20 ㎍/mL of fibronectin was used (as tested during an early and late passage). Levels of expressed Pax7 and MyoD1, assessed using immunocytochemistry, were highest in cells grown using fibronectin-coated dishes. The proliferation of gelatin/fibronectin mixed coatings had no significant effect on porcine satellite cells. The concentration of 5 ㎍/mL fibronectin coated dishes showed the lowest doubling time and maintained expression of Pax7. Conclusion: Fibronectin with 5㎍/mL effectively maintains porcine satellite cells, a discovery that will be of interest to those developing the next generation of artificial meats.

Developing the Satellite Image based e-Thematic Construction and Management System -Case Study of Supporting Forest Administrative Service- (위성영상기반 전자주제도 작성 및 관리시스템 개발 - 산림행정업무지원서비스를 사례연구로 -)

  • Jo, Myung-Hee;Jo, Yun-Won
    • Journal of the Korean Association of Geographic Information Studies
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    • v.9 no.1
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    • pp.89-100
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    • 2006
  • Recently the dramatical development of domestic spatial information technology and the successful construction of Korea NGIS(Nation Geographic Information System) have been the foundation of the scientific national territory utilization and management. However, there still exists the original problems to construct the thematic maps for supporting the various administrative services because administrative officials tend to depend on paper maps and inventories to generate spatial information, process, upgrade and manage. In this situation, there is a greater need to develop GIS system for the effective construction of various thematic maps. In this study, the satellite image based high accurate e-thematic construction and management system was developed to support the forest administrative service such as generating user based forest thematic maps, modifying them, analyzing and outputting through GIS, GPS and satellite images. For the case study, the previous forest paper map of Jeju Island was converted in format of raster and vector data using satellite images to maintain more exact location information so that this system helps to manage domestic spatial information scientifically and effectively within shorter time then support the standard for domestic spatial information. Moreover, this system plays the role of DSS(Decision Supporting System) for forest administrative affairs by integrating the attribute data, managing the GPS data and linking the multimedia data. For this, the additional main objective of this study was acquired powerful GIS component, which is called as e-mapping component, so that it could be regarded as enabling interoperability and reusability within this application. For the future works, the essential element idea and technology in this study could be applied very usefully to other official works such as constructing thematic maps and supporting the desired affairs.

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Performance of an Adaptive D2D Channel Modeling Scheme for Satellite Wireless Package Systems (이동단말용 위성 통신 무선 패키지 시스템을 위한 적응적 D2D 채널 모델링 기법의 성능)

  • Hwang, Yu Min;Cha, Jae Sang;Kim, Jin Young
    • Journal of Satellite, Information and Communications
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    • v.10 no.1
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    • pp.17-21
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    • 2015
  • In this paper, we introduce satellite communication for new wireless disaster network to be built on the basis of amateur radio HR (HAM Radio) as a wireless package system, and channel environments of a D2D terminal that tries to connect and communicate with the wireless disaster network. In this disaster network, we propose a LOS component ratio based adaptive channel modeling approach to accurately estimate a variety of channels whose the D2D terminal could have and smoothly transfer to the level of multimedia data based on the Okumura-Hata channel model. As a result of computer simulation, performance of the proposed method was compared with the that of Okumura-Hata model of open area and urban area model and we were confirmed that there is a gain of BER performance from the results of the computer simulation.